AU2011226779B2 - Electronic lock - Google Patents

Abstract

The specification discloses a latch plate assembly (10) including a pivot pin (19) therefor, the pivot pin (19) having a first shaft portion (29) defining a longitudinal pivot axis, the first shaft portion (29) having a first end region (31) at one end of the pivot pin (19), the pivot pin (19) further including a second end region (35) at an opposite end to said first end region (31), the pivot pin (19) still further including a longitudinally extending groove (37) being axially open at or adjacent the first end region (31), the first end region (31) also including an axially extending flat face (34), the second end region including engagement formation means (36) enabling the pivot pin to be rotated about the longitudinal pivot axis, the latch plate assembly (10) also including a latch plate (17) with a striker portion (20) and a mounting portion (21), the mounting portion (21) having a bore (22) for operationally receiving the pivot pin (19), the bore (22) having a first bore zone spaced from a second bore zone to pivotally mount spaced parts (31, 32) of the first shaft portion (29) of the pivot pin (19), the bore (22) also including an intermediate bore zone between said first and said second bore zones, the mounting portion (21) also including an access opening (39) leading to the intermediate bore zone whereby a torsion spring (18) is positionable in the intermediate bore zone with the pivot pin passing therethrough, the torsion spring (18) having a first end tab (25) engaged in the longitudinally extending groove (37) and a second end tab (27) held by the latch plate (17). 30' 34 3%

Description

Pool Section 29 Regulation 32(2) AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Application Number: Lodged: Invention Title: Electronic lock The following statement is a full description of this invention, including the best method of performing it known to us: P111H#AU/0610 1 ELECTRONIC LOCK FIELD OF THE INVENTION This invention relates to improvements in electronic locks. BACKGROUND ART 5 The specification of international patent application no. PCT/AU2003/001104 discloses various electronic lock configurations for use with doors and in one disclosed embodiment discloses an arrangement where the components of the lock are maintained in the striker mounted in the door surround rather than in the component of the lock that is mounted in the door. 10 The disclosed arrangement includes a pivotal latch plate mounted in the striker for pivoting movement about an upright pivot pin with the latch plate being biased by a torsion spring mounted about the pivot pin within a bore formed in the latch plate. The latch plate is normally held by electronic means in a latching condition but can be released therefrom by a person with an access actuator operating 15 sensor means connected to the electronic means. The torsion spring normally biases the latch plate towards the latching position when the latch plate is freed from control by the electronic means. While the disclosed electronic lock as briefly described in the foregoing does operate satisfactorily when assembled, it has proved to be very difficult to assemble the torsion spring, pivot pin and latch 20 plate structures as disclosed in a normal manufacturing environment. An objective therefore of the present invention is to provide an improved pivoting latch plate assembly, including improved parts therefor, that will enable more convenient and safer assembly of these parts in an electronic lock of the above discussed type. 25 SUMMARY OF THE INVENTION According to a first aspect of the invention there is provided a pivot pin for a pivoting latch plate in an electronic lock or latch, said pivot pin having a first shaft portion defining a longitudinally extending pivot axis, a first end region at one end of said first shaft portion, and a second end region at an opposed end of 30 said first shaft portion, said pivot pin including a longitudinally extending groove formed in at least part of said first shaft portion being axially open at or adjacent said first end region, said pivot pin further including an axially extending flat face formed in said first end region, and said second end region including engagement 2 formation means enabling said pivot pin to be rotated at least partially about said pivot axis. Conveniently, in one preferred embodiment, the flat face extends from a free end of said first end region. Preferably the groove is formed in at least part 5 of said first shaft portion and in said flat face. In a possible alternative, the groove may be formed only in said first shaft portion and includes an axially open end face at an axially inner end of said flat face. Conveniently, the present invention may also comprise a pivot pin assembly including a pivot pin as described above and further having a torsion 10 spring with a plurality of spring turns positioned over said first shaft portion and an inwardly formed first end tab engaged in said groove, the torsion spring having a second end tab formed in a direction extending outwardly from said spring tums. In a further preferred embodiment, the present invention may provide a pivot pin and latch plate assembly including a pivot pin assembly as defined in the 15 preceding paragraph in combination with a latch plate, said latch plate having a striker portion and a mounting portion with a pivot pin mounting bore formed therethrough, said pivot pin mounting bore having first and second spaced bore zones to pivotally mount spaced parts of the first shaft portion of the pivot pin, said pivot pin mounting bore having an intermediate bore zone between said first 20 and said second bore zones, said mounting portion further including an access opening leading to said intermediate bore zone whereby said torsion spring is positionable in said intermediate bore zone passing laterally through said access opening with said second end tab being held, in use, by said latch plate. Conveniently the second end tab may be held by engagement means 25 forming part of the latch plate and more specifically by a perimeter edge of the access opening in the mounting portion. The intermediate bore zone of the mounting bore may have a diameter greater than at least one of said first and said second bore zones. Conveniently, the pivot pin and latch plate assembly may be assembled by 30 passing said torsion spring through said access opening to be positioned in said intermediate bore zone, by passing said pivot pin into said mounting bore passing through said torsion spring while positioning the first end tab of said torsion spring in said groove, and rotating said pivot pin within said mounting bore to provide a 3 preloaded tension in said torsion spring and thereafter engaging said flat face against an engagement abutment to prevent said pivot pin rotating and maintaining said preloaded tension in said torsion spring. Such an assembly process can be achieved safely and easily by engaging the formation means at 5 the second end region of the pivot pin by a suitable tool to effect the rotation of the pivot pin to cause preloading of tension in the torsion spring. Conveniently, the engagement formation means can be suitable recesses engageable with any conventional screw driver head (eg flat or Phillips head), or any other formations engageable with a drive head of a suitable tool. 10 A preferred embodiment of the present invention will now be described with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS Fig 1 is a front perspective view of a door surround mountable latch plate assembly with the latch plate moved to its open position against the closing force 15 applied by the torsion spring; Fig 2 is an exploded view of the latch plate, torsion spring and pivot pin of the assembly shown in Fig 1; Fig 3 shows the exploded parts shown in Fig 2 in an assembled condition; Fig 4 shows a view similar to Fig 3 from the reverse side of the latch plate; 20 and Figs 5 and 6 are rear perspective views with portions removed to show operation of the latch plate assembly. DESCRIPTION OF THE PREFERRED EMBODIMENT SHOWN IN THE DRAWINGS 25 Referring to the drawings, Fig 1 shows a door surround mountable latch plate assembly 10 having a front facia plate 11 and a body portion 12 such that the body portion 12, in use, is mounted in a suitable recess in the door surround (not shown) with the facia plate 11 being mounted thereto by fasteners passing through openings 13, 14. The assembly 10 further includes a latch recess 15 30 opening through the front facia plate 11 which has one lateral face 16 opened or closed by a pivoting latch plate 17 shown in an open configuration in Fig 1. The latch plate assembly 10 includes a sub assembly 28 comprised of the latch plate 17, a torsion spring 18 and a pivot pin 19 shown in Figs 2, 3 and 4.

4 The latch plate 17 includes a striker portion 20 and a mounting portion 21 having a mounting bore 22 formed therein. The torsion spring 18 has a plurality of spring turns 23 with a first end 24 with an inwardly bent tab portion 25. The torsion spring 18 has a second end 26 with an outwardly bent tab portion 27. 5 The pivot pin 19 has a first shaft portion 29 with an intermediate zone 30 of smaller diameter between a first end zone 31 and a second end zone 32. The first and second end zones 31, 32 correspond in diameter to end zones of the mounting bore 22 such that the pivot pin 19 can be slid into the mounting bore 22 of latch plate 17 with the end zones of the mounting bore being journalled on the 10 end zones 31, 32 of the pivot pin 19 for relative pivoting movement. Conveniently the end zones 31 and 32 of the pivot pin 19 can be of equal diameter or alternatively, the zone 32 could have a diameter greater than that of the zone 31. At a first end 33 of the pivot pin 19 adjacent said first end zone 31 of the first shaft portion 29, a flat, generally diametral face 34 is formed extending a short axial 15 length along the pivot pin 19. At the second opposed end 35, a diametral slot 36 is formed engageable with a flat head screw driver to enable the pivot pin 19 to be rotated during assembly as described hereafter. Other end formations could be formed instead of the slot 36 cooperable with a complementary shaped tool to effect rotation of the pivot pin 19 as described hereafter. Finally, a longitudinally 20 extending groove 37 commencing in the illustrated embodiment at the first end 33 extends along the pivot pin 19 to end in the intermediate zone 30 of the first shaft portion 29. While the groove 37 is shown in the annexed drawings as being formed in both the flat face 34 and the first shaft portion 29, it is possible for the groove 37 to start only at the step face 38 at the inner end of the flat face 34 and 25 extend therefrom along the first shaft portion 29. As best seen in Figs 3 and 4, the mounting portion 21 of the latch plate 17 includes a lateral rectangular access opening 39 sized to allow the torsion spring 18 to be positioned in the mounting bore 22 by passing laterally through the access opening 39. In doing so, the outwardly bent end tab 27 of the torsion 30 spring 18 is engaged by and held by a perimeter edge 40 of the mounting portion 21 (see Fig 4). In this configuration, the pivot pin 19 is slid into the mounting bore 22 passing through the turns 23 of the torsion spring 18 and in doing so, the inwardly bent end tab 25 of the torsion spring 18 slides into and is held by the 5 longitudinal groove 37 in the pivot pin 19. Thereafter, the pivot pin 19 is rotated by engaging the formations 36 with a suitable tool and the flat face 34 of the pin 19 is engaged with a suitably located abutment face 41 on the body portion 12 to prevent undesired rotation of the pivot pin 19 to maintain tension in the torsion 5 spring 18. In doing so, the torsion spring 18 has been readily and conveniently preloaded with a suitable tension to provide, in use, an urging force to pivot the latch plate 17 towards its closed position, ie closing the face 16 of the recess 15 in the body portion 12 (Fig 1). The latch plate 17 might be locked by electronic control means (not shown) in the closed position or selectably unlocked and when 10 unlocked, the latch plate 17 can be readily moved against the urging forces of the spring 18 to move to the open position as shown in Fig 1. Many modifications and variations of the latch arrangement illustrated in the annexed drawings are possible and would be apparent to those skilled in this art. The present invention covers such modifications and variations within the 15 scope of the annexed patent claims.

Claims (9)

1. A pivot pin for a pivoting latch plate in an electronic lock or latch, said pivot pin having a first shaft portion defining a longitudinally extending pivot axis, a first end region at one end of said first shaft portion, and a second end region at an 5 opposed end of said first shaft portion, said pivot pin including a longitudinally extending groove formed in at least part of said first shaft portion being axially open at or adjacent said first end region, said pivot pin further including an axially extending flat face formed in said first end region, and said second end region including engagement formation means enabling said pivot pin to be rotated at 10 least partially about said pivot axis.

2. A pivot pin according to claim 1 wherein said flat face extends from a free end of said first end region.

3. A pivot pin according to claim I or claim 2 wherein said groove is formed in at least part of said first shaft portion and in said flat face. 15

4. A pivot pin according to claim 1 or claim 2 wherein said groove is formed only in said first shaft portion and includes an axially open face at an axially inner end of said flat face.

5. A pivot pin assembly including a pivot pin according to any one of claims 1 to 4 and a torsion spring with a plurality of spring turns positioned over said first 20 shaft portion and an inwardly formed first end tab engaged in said groove, the torsion spring having a second end tab formed in a direction extending outwardly from said spring turns.

6. A pivot pin and latch plate assembly including a pivot pin assembly according to claim 5 in combination with a latch plate, said latch plate having a 25 striker portion and a mounting portion with a pivot pin mounting bore formed therethrough, said pivot pin mounting bore having first and second spaced bore zones to pivotally mount spaced parts of the first shaft portion of the pivot pin, said pivot pin mounting bore having an intermediate bore zone between said first 7 and said second bore zones, said mounting portion further including an access opening leading to said intermediate bore zone whereby said torsion spring is positionable in said intermediate bore zone passing laterally through said access opening with said second end tab being held, in use, by said latch plate. 5

7. An assembly according to claim 6 wherein said second end tab is held by engagement means forming part of the latch plate.

8. An assembly according to claim 7 wherein said engagement means is formed by a perimeter edge of said access opening.

9. An assembly according to any one of claims 6 to 8 wherein said 10 intermediate bore zone has a diameter greater than at least one of said first and said second bore zones. LOCK FOCUS PTY LTD WATERMARK PATENT & TRADE MARK ATTORNEYS P33726AU00