NZ280010A - Sliding bolt locking mechanism has a flush plate with an elongated sleeve member with a bore in which a shaft and locking device reciprocates - Google Patents

Description

28 0 0 1 0 PATENTS FORM 5 Number:280010 PATENTS ACT 1953 Dated: September 13, 1995 COMPLETE SPECIFICATION A SLIDING BOLT LOCKING MECHANISM We, F. L. BONE & SON LIMITED, of 208 Eastbourne Street East, Hastings, New Zealand being a New Zealand company do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement. -1 - , ^ 28 0 0 10 This invention relates to an improved sliding bolt locking mechanism.

BACKGROUND TO THE INVENTION Sliding bolt mechanisms which consist of two parts are known. In such sliding bolt 5 mechanisms, the first part comprises a bolt guided in a channel so the bolt will have longitudinal sliding movement within the channel. An end of the bolt can be extended out of the guide channel to engage within a sleeve which forms the second part of the sliding bolt mechanism. The first part of the sliding bolt mechanism is generally attached to the object to be closed such as a door or a window and by appropriate manipulation of the bolt, 10 the end of the bolt can be extended to engage in the sleeve which forms the second part, to lock the object in a closed position. To unlock the object from the closed position, the bolt can be retracted into the guide channel to enable the object to be opened. Such sliding bolt mechanisms can be in the form of a flush bolt, a socket bolt or a necked bolt, all of which are generically referred to herein as a sliding bolt.

Known sliding bolt mechanisms are also generally provided with a means whereby the bolt can be partly rotated within the guide channel. In a known construction, a peg extends radially out of the bolt so the peg can be located in an appropriate recess in the guide channel, to maintain the bolt in either an extended or retracted position. Such 20 known types of sliding bolt mechanisms, while they are effective in operation have little aesthetic appeal because substantially all of the mechanism is exposed..

In a modification of a known sliding bolt mechanism, the bolt mechanism is located behind a flush plate and an elongated slot is provided in the fli ' ' ' ' ' which 28 0 0 1 0 operates the sliding bolt, can extend through the slot in the flush plate. Such a mechanism is generally known as a flush bolt. The mechanism of the flush bolt is positioned behind the flush plate and is housed within a cutout formed in the surface to which the flush bolt is to be attached, with the cut out being hidden by the flush plate so all that is normally 5 visible is the outside face of the flush plate and the knob. Because of the construction of the flush bolt, it is not possible to utilise the traditional means for maintaining the bolt in an extended or retracted position. One known method of overcoming this was to utilise a trigger mechanism in connection with the slot so that when the bolt is in the extended position, it was necessary to release the trigger mechanism before the bolt can be retracted.

Various other sliding bolt mechanisms are also known, but they all suffer from the disadvantage of either being cumbersome or expensive to manufacture or else they are not sufficiently positive in their action particularly in regard to the mechanism for securely locating the sliding bolt in an extended or a retracted position.

OBJECT OF THE INVENTION It is therefore an object of this invention to provide an improved sliding bolt mechanism that will minimise the above disadvantages or which will at least provide the public with a useful choice.

DISCLOSURE OF THE INVENTION Accordingly, one form of the invention may be said to comprise a sliding bolt locking mechanism consisting of; " "i* 28 0 0 1 0 a base plate having an outer surface and an inner surface with a guide channel projecting from said inner surface and including a bore, an elongated blind slot formed in the base plate and having a main axis substantially parallel to the longitudinal axis of said bore and communicating with the bore, said slot terminating at each end in an enlargement, ' a shaft having reciprocal sliding movement within the bore, locking means associated with said shaft and including a locking plate which is spring urged radially away from said shaft and which has means to engage with an enlargement of said blind slot to thereby prevent reciprocal movement of the shaft in said bore until said plate has been depressed towards said shaft to disengage the locking means from said enlargement.

Preferably said locking plate is shaped to engage within a recess in the shaft and is spring urged radially away from the said soaft by spring means located between said locking plate and said recess in the shaft.

Preferably the means to engage with an enlargement of the blind slot comprises a projection on said locking plate.

Preferably the said projection comprises a collar. 28 0 0 Preferably a shank projects radially from said locking plate with the junction of the shank with the locking plate being surrounded by said collar and wherein the distal end of '1". shank terminates in a knob.

Preferably the locking plate can move radially away from the axis of the shaft within the said recess under the urging of the spring means when the said projection registers with an enlargement in the said slot and wherein the said locking plate can be depressed to disengage the projection from the said enlargement.

Preferably a slot is formed in the wall of the guide channel and extends in a direction parallel to the bore of the guide channel from one end of the guide channel and a block extends radially from the shaft through said slot, said block including a latch assembly.

Preferably the latch assembly includes a threaded shaft formed to engage within a correspondingly threaded hole in the block in a manner that the said threaded shaft will extend from the said block in a direction substantially parallel to the longitudinal axis of the shaft.

Preferably the block includes more than one said threaded hole.

Preferably the spring means comprises at least one compression spring located between the locking plate and the said shaft. 28 0 0 1 0 BRIEF DESCRIPTION OF THE DRAWINGS «- v ~ A preferred form of the invention will now be described with the aid of the accompanying drawings wherein; Fig. 2 is a third quarter view from above showing one form of the flush type sliding bolt of the present invention in an assembled condition.

DESCRIPTION OF THE PREFERRED EMBODIMENT A typical sliding bolt mechanism incorporating the teachings of the present invention will now be described. In the drawings only the first part of a sliding bolt is shown. The second part which is not shown in the drawings is the anchor member and can be the usual 15 tubular member such as a sleeve, which is permanently affixed to a surround of the door or window. The sliding bolt mechanism depicted in the drawings is a flush type bolt and includes a flush plate 1 which may be conveniently moulded from metal, plastics material such as nylon or the like as is known. Mounting holes 2 are provided in the flush plate 1 so the flush plate can be secured to the object on which the bolt mechanism is to be 20 mounted. An elongated guide channel 3 which may be formed of the same material as the flush plate 1 is secured to or otherwise formed on the undersurface of the flush plate 1. The guide channel has a bore 4 the axis of which is substantially parallel to the major axis of the flush plate, with the bore preferably extending the length of the guide channel 3. The flush plate also includes a blind slot 22 (see Fig. 2) which comprises a central portion Fig. 1 is a view of the component parts of the flush type sliding bolt mechanism shown in an exploded view, and 28 0 0 1 of substantially constant diameter and which extends in a u'r iction parallel with the axis of the bore 4 and terminates at either end in an enlargement 23.

A shaft 7 which has a diameter that will enable it to have sliding reciprocal 5 movement within the bore 4 of the guide channel 3, has an overall length which may be the same but which is preferably less than thClength of the guide channel 3. The shaft 7 also includes a recess 10 which extends in the axial direction of the shaft. A locking plate 11 which can be formed of the same material as the shaft has approximately the same length as the recess 10 but has less radial dimension than the recess 10 so it can engage 10 fully within the recess 10 and is therefore capable of being substantially fully located within the recess 10.

The locking plate 11 has a mounting hole 12 which is screw threaded to receive a screw threaded end of a shank 13 of a locking knob 14. The locking plate 11 also 15 includes a projection which may be in the form of a collar 15 which surrounds the mounting hole 12 with the diameter of the collar being such that the collar can engage in the enlargement 15. Spring means which may for instance be a leaf spring or the coil springs 16, are located between the locking plate 11 and the base of the recess 10, so the locking plate will be spring urged away from the shaft 7. The action of the spring means 20 and of the locking plate is such that the locking plate can be compressed against the pressure of the spring means, so the locking plate will lie wholly within the recess 10 and can move bodily away from the shaft 7 until the arcuate outer edge of the locking plate contacts the bore 4 of the guide channel 3.

•~"P ft 28 0 0 1 0 In the configuration depicted in Figure 2, the bolt is in the extended (locked) position. In this position, the spring means has spring urged the locking plate 11 away from the axial centre of the shaft 7 and the collar IS has engaged in the enlargement 23. When in this position, the shaft 7 is locked and cannot be reciprocated within the guide channel 3. To move the bolt from the extended position shown in Figure 2, to a retracted (open) position, the knob 14 is depressed to'move the shank 13 and the locking plate inwardly towards the axis of the shaft 7 against the urging of the spring means until collar 15 disengages from the enlargement 23. When in this position, the shaft 7 can be slid along the bore 4 of the guide channel 3 until the shank 13 of the knob 14 contacts the other end of the slot 22. If the pressure on the knob is released, the shank can move outwardly through the enlargement to allow the collar 15 to enter into the enlargement 23 at that end of the slot so prevent longitudinal movement of the shaft until the knob is again depressed.

It will thus been seen that unless the knob 14 is depressed, the bolt 19 must remain in either an extended or a retracted position and cannot be moved from that position until the knob is depressed. When the knob is depressed, this will move the locking plate 11 into the recess 10 and thus the collar 15 out of engagement with the enlargement 23. The knob and the shaft 7 can then slide between the locked and unlocked positions.

A slot 5 is formed in the wall of the guide channel 3 opposite the junction of the guide channel 3 with the flush plate 1 and extends longitudinally along the wall from one end of the guide channel in the same axial direction as the bore 4. One end of the shaft 7 is provided with a block 8 which extends substantially radially from the shaft and which 28 0 0 10 is located approximately 180° opposite the recess 10 with the block being joined to the shaft 7 by a portion of reduced size to form a neck 9. The block 8 and the shaft 7 can be moulded from a suitable metallic material and can be formed as a composite moulding. The neck has a width that will enable it to be engaged within the slot 5, to allow the shaft 5 7 to slide within the bore 4 of the guide channel, with the movement of the shaft being determined by the length of the slot so that when the neck of the block contacts the end of the slot, further movement in that direction of the shaft 7 will be halted. longitudinal axes of which are substantially parallel to the longitudinal axis of the shaft 7. A latch assembly 19 which may in one form consist of a shank 18 which terminates in an enlargement 19a, is locatable in one of the threaded holes 17 by having the end opposite the enlargement 19a screw threaded. It is preferred to provide more than one hole 17 to allow for different locations of attachment of the latch assembly 19 to the block 8.

In the highly preferred form of the invention as hereinbefore described, the locking arrangement is obtained by a projection from the locking plate entering an enlargement 23, ' ut it is to be understood that other suitable constructions as will be readily apparent can be utilised. For instance, the shank 13 can be formed with a portion of enlarged diameter 20 which can protrude into the enlargement. In another form the shank 13 can include a portion of reduced diameter which is the same or less than the width between the walls of the slot 22. In this form the remainder of the shank will have a diameter that substantially equates to the diameter of the enlargement. To move the shaft 7, it is necessary to depress the shank until the portion of reduced diameter registers with the slot.

The block 8 includes at least one and preferably more, threaded holes 17, the £8 0 0 1 0 In the foregoing description of the sliding bolt mechanism, the preferred form is described as being applied to a flush bolt but it will be understood that the mechanism can also be utilized with a surface mounting bolt. In such a version the locking plate can be housed on the outside of the base member and the blind slot can be formed in the housing. 5 Various other modifications and alterations to form a socket bolt or a neck bolt will also be apparent. ' Although in a highly preferred from, the sliding bolt mechanism includes the block 8 and the latch assembly 19, it is to be understood that in certain circumstances the block 10 can be dispensed with and the shaft can be extended out of the guide channel for engagement with an anchor member. In yet another modification, the exposed end of the shaft can be provided with a cranked portion which extends into a latch member for engagement with an anchor member.

The foregoing represents a description of preferred forms of the invention. It will be understood that having been apprised of the principles and the precepts of the invention, a person skilled in this particular art will be able to make modifications and amendments to the particular manner of carrying the invention into effect and yet still come within the basic concept of the invention. All such modifications and amendments are intended to be 20 included within the scope of this present invention as defined in the appended claims.

Claims (11)

WHAT WE CLAIM IS: 28 0 0 1 0

1. A sliding bolt locking mechanism consisting of; a base plate having an outer surface and an inner surface with a guide channel projecting from said inner surface and including a bore, an elongated blind slot formed in the base plate and having a main axis substantially parallel to the longitudinal axis of said bore and communicating with the bore, said slot terminating at each end in an enlargement, locking means associated with said shaft and including a locking plate which is spring urged radially away from said shaft and which has means to engage with an enlargement of said blind slot to thereby prevent reciprocal movement of the shaft in said 15 bore until said plate has been depressed towards said shaft to disengage the locking means from said enlargement.

2. The sliding bolt mechanism as claimed in claim 1, wherein said locking plate is shaped to engage within a recess in the shaft and is spring urged radially away from the 20 said shaft by spring means located between said locking plate and said recess in the shaft.

3. The sliding bolt mechanism as claimed in claim 2, wherein the means to engage with an enlargement of the blind slot comprises a projection on said locking plate. 5 10 a shaft having reciprocal sliding movement within the bore, - 11 - 28 0 0 1 0

4. The sliding bolt mechanism as claimed in claim 3, wherein the said projection comprises a collar.

5. The sliding bolt mechanism as claimed in claim 4, wherein a shank projects radially 5 from said locking plate with the junction of the shank with the locking plate being surrounded by said collar and wherein the distal end of the shank terminates in a knob.

6. The sliding bolt mechanism as claimed in claim 3, 4 or 5, wherein the locking plate can move radially away from the axis of the shaft within the said recess under the urging 10 of the spring means when the said projection registers with an enlargement in the said slot and wherein the said locking plate can be depressed to disengage the projection from the said enlargement.

7. The sliding bolt mechanism as claimed in any one of the preceding claims, wherein 15 a slot is formed in the wall of the guide channel and extends in a direction parallel to the bore of the guide channel from one end of the guide channel and a block extends radially from the shaft through said slot, said block including a latch assembly.

8. The sliding bolt mechanism as claimed in claim 7, wherein the latch assembly 20 includes a threaded shaft formed to engage within a correspondingly threaded hole in the block in a manner that the said threaded shaft will extend from the said block in a direction substantially parallel to the longitudinal axis of the shaft. - 12- 28 0 0 1 0

9. The sliding bolt mechanism as claimed in claim 8, wherein the block includes more than one said threaded hole.

10. The sliding bolt mechanism as claimed in any one of the preceding claims 2 to 9, 5 wherein the spring means comprises at least one compression spring located between the locking plate and the said shaft. '

11. The sliding bolt mechanism substantially as herein described with reference to the accompanying drawings. END OF CLAIMS - 13 - GREG WEST-WALKER & CO