AU2002309074B2 - A Latch - Google Patents

Description

-1- Regulation 3.2

AUSTRALIA

PATENTS ACT, 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

Name of Applicant: Actual Inventor: INGERSOLL-RAND ARCHITECTURAL HARDWARE LIMITED PETER MARK HILL, MICHAEL RAYMOND PERCY, VINCENT KIERON KING Address for service in Australia: A J PARK, Level 11, 60 Marcus Clarke Street, Canberra ACT 2601 Invention Title: A Latch The following statement is a full description of this invention, including the best method of performing it known to me/us -1- A LATCH TECHNICAL FIELD The present invention relates to latch assemblies.

BACKGROUND ART Many forms of latch assembly of a kind capable of latching the protruding end of a lath assembly into a striker plate of a door or the like are known.

Generally the striker plate cams the end and the lath withdraws against a bias and thereafter only reassumes its original extended condition under the effect of the bias when over the latch opening of the striker plate.

SUMMARY OF THE INVENTION The present invention is directed to such latch assemblies, mouldings applicable therefore assemblies or combinations of components of such latch assemblies and related uses.

Accordingly in a first aspect the present invention consists in a latch assembly comprising or including a moulded case, a moulded cap complementary to the case, and a moulded lath insertable so as to be guideably moveable from a partly extended condition ("latching condition") beyond the confines of the case and cap defined housing to a less or non-extended condition ("unlatching condition"), a follower adapted to be sufficiently rotatable to at least retract the lath from a latching condition relative to the housing to the unlatching condition, and a biasing element or elements adapted to bias the lath outwardly of the housing formed by the co-acting case and cap to the latching condition whenever increasingly energised or energised by any forced movement of the lath (whether by the follower or otherwise, a striker plate acting on the lath end) into the housing whether fully to an unlatching condition or otherwise.

Preferably the case, cap and lath are moulded in zinc or a zinc alloy.

-2- Preferably also the follower although, less preferred, it can be of a sintered powder material.

Preferably said case includes a flange to co-act with a face plate to be associated with the latch.

Preferably the moulding of (at least) the case, cap and lath components has been collectively in a die assembly such that, even if the specific case, cap and/or lath were not moulded together, over a production run there has been a substantial correspondence in number of at least each component.

Preferably or possibly also the follower.

Preferably for example, a single tool for moulding moulds at least a single one of each of the case, cap and lath components.

Preferably said case and cap components are adapted to index one to the other to their final position.

Preferably force during assembly is required to secure the two components in their indexed condition, either a press or loose indexing fit of one or more indexing interaction in which relationship when packaged and/or used they maintain or are held) or some deformational forcing such as deforming a protuberant member of one or other of the components to hold the two in their co-acting indexed conditions similar to that of a rivet)).

Preferably one or other of the case and cap (preferably the case) includes a feature or face against which, as a biasing element, a compression spring can be inserted to act on the lath.

Preferably the follower is adapted to receive a square sectional shaft that can pass through and not fetter the lath movement.

Preferably the cap includes features substantially as hereinafter described with reference to any of the accompanying drawings.

Preferably the case includes any of the features hereinafter described with reference to any of the accompanying drawings.

Preferably the lath includes any of the features hereinafter described with reference to any one of the accompanying drawings.

-3- In another aspect the present invention consists in a latch assembly comprising or including a case, a cap complementary to the case, a moulded lath insertable so as to be guideably moveable from a partly extended condition beyond the confines of the housing defined by the case and cap defined housing to a less or non-extended condition, a biasing element to bias the lath to a latching condition relative to the housing, and a follower for the lath adapted to be rotatable sufficiently to retract the lath from a latching condition relative to the housing, wherein the case, cap and lath are such as to provide for horizontal fixing through the assembly in a door or the like cavity.

In another aspect the invention is, as a pack, components of an assembly of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS A preferred form of the present invention will now be described with reference to the accompanying drawings in which; Figure 1 is a plan view of a lath in accordance with the present invention, such a lath having been moulded in zinc, Figure 2 is an elevational view of the lath of Figure 1 in the direction AA, Figure 3 is an end view of the lath as shown in Figure 2 from the end BB, Figure 4 is an elevational view similar to that of Figure 2 in respect of the lath, but this time showing the case, Figure 5 is a sectional view at CC, Figure 6 is an end view DD, Figure 7 is section at EE, the case of Figures 4 through 7 preferably having been moulded in zinc, Figure 8 is an elevational view in a manner similar to the elevational views of Figures 2 and 4 but this time of the cap, Figure 9 is a section at FF of the case of Figure 8, Figure 10 is an end view GG of the case, -4- Figure 11 is a plan view showing a lath as shown in Figure 1 interposed to reciprocate between a case as shown in Figure 5 in section and a complementary cap as shown in Figure 9, the cap being indexed and retainable with the complementary case, Figure 12 is an elevational view of the arrangement as shown in Figure 11 but with, for example, a stainless steel facing plate indexed to or attached to the lath emergent end of the assembly so as to co-act therewith, the X depicting the abutment faces respectively between the lath and part of an indexing and retention projection of the case which will locate a compression string to urge the lath from the withdrawn condition, as shown in Figure 11, to an emergent latching condition (not shown), Figure 13 is a transparent view of the assembly of Figures 11 and 12, Figure 14 is a view of the rotatable follower, Figure 15 is a view HH of the plate indexed to or attached at the emergent end of the assembly, and Figure 16 is a moulding in accordance with the present invention where it is shown how it is possible to provide tooling whereby for each lath moulded there is also moulded a case and cap.

DETAILED DESCRIPTION OF THE INVENTION In the preferred form of the present invention each of the main components, the lath, the case and the cap is a moulded member and preferably each is moulded from a substantially identical zinc or zinc containing material. Likewise preferably also the follower.

The lath as shown has a latching face 1 opposite its camming face 2 which allows normal door closure. Shown through the centre of the lath are large openings 3 and 4 to accommodate the compression spring (not shown), the square shaft which is to pass through the square opening 5 in the follower 6 (see Figure 14) as well as the horizontal fixings screws) that will pass through the door and through openings 7 and 8 in the cap and openings 9 and 10 in the case.

The spring acts on that face 11 of the lath shown in Figure 2 with the other end of the spring acting against the face 12 shown in Figure The rotatable follower has one or other of its faces 23 adapted to withdraw the lath by an interaction with a respective face 24 of the lath.

The emergent member of which the face 12 forms part is adapted to have a protuberant end 13 adapted to pass through and emerge from the complementary opening 14 of the cap so that it can then be deformed by stamping or the like to hold the components in juxtaposition, the remainder of the indexing being reliant upon indexing protuberances 15 of the case which are received into the complementary openings 16 of the cap. It does not matter whether the indexing is of some or all of the male members from one only of the cap or case.

The nature of assembly is simple since the latch assembly has five components only, the lath, the case, the cap, the follower and the compression spring. Whilst forms of latch that rely upon features of assembly of the present invention can include multiple springs if soft closing is required in a manner known in the art), for cost preferably a single spring only is utilised.

In final assembly, if desired, a facing plate 17 of stainless steel can be affixed or associated with the end flange 18 of the case to have pressed flanges thereof located in the openings 19 and adapted to receive fixing screws therethrough.

Figure 16 shows removed from a tool the breakaway formations of a pair of cases a pair of caps 21 and a pair of laths 22 when all are moulded together.

Claims (14)

1. A latch assembly comprising or including a moulded case, a moulded cap complementary to the case, and a moulded lath insertable so as to be guideably moveable from a partly extended condition ("latching condition") beyond the confines of the case and cap defined housing to a less or non-extended condition ("unlatching condition"), a follower adapted to be sufficiently rotatable to at least retract the lath from a latching condition relative to the housing to the unlatching condition, and a biasing element or elements adapted to bias the lath outwardly of the housing formed by the co-acting case and cap to the latching condition whenever increasingly energised or energised by any forced movement of the lath (whether by the follower or otherwise, a striker plate acting on the lath end) into the housing whether fully to an unlatching condition or otherwise.

2. An assembly of claim 1 wherein at least the case, cap and lath are moulded in zinc or a zinc alloy.

3. An assembly of claim 1 or 2 wherein said case includes a flange to co-act with a face plate to be associated with the latch.

4. An assembly of any one of claims 1 to 3 wherein the moulding of (at least) the case, cap and lath components has been collectively in a die assembly such that, even if the specific case, cap and/or lath were not moulded together, over a production run there has been a substantial correspondence in number of at least each component.

An assembly of any one of the preceding claims wherein at least a single tool for moulding moulds at least a single one of each of the case, cap and lath components.

6. An assembly of claim 5 wherein the single tool moulds also the follower.

7. An assembly of any one of the preceding claims wherein said case and cap components are adapted to index one to the other to their final position.

8. An assembly of claim 7 wherein force during assembly or deformational forcing is required to secure the case and cap components in their indexed condition. -7-

9. An assembly of any one of the preceding claims wherein one or other of the case and cap includes a feature or face against which, as a biasing element, a compression spring can be inserted to act on the lath.

An assembly of any one of the preceding claims wherein the follower is adapted to receive a square sectional shaft that can pass through and not fetter the lath movement.

11. An assembly of any one of the preceding claims wherein the cap includes features substantially as herein described with reference to any of the accompanying drawings.

12. An assembly of any one of the preceding claims wherein the case includes any of the features hereinafter described with reference to any of the accompanying drawings.

13. An assembly of any one of the preceding claims wherein the lath includes any of the features hereinafter described with reference to any one of the accompanying drawings.

14. A latch assembly comprising or including a case, a cap complementary to the case, a moulded lath insertable so as to be guideably moveable from a partly extended condition beyond the confines of the housing defined by the case and cap defined housing to a less or non-extended condition, a biasing element to bias the lath to a latching condition relative to the housing, and a follower for the lath adapted to be rotatable sufficiently to retract the lath from a latching condition relative to the housing, wherein the case, cap and lath are such as to provide for horizontal fixing through the assembly in a door or the like cavity. As a pack, the components of an assembly of any one of the preceding claims.