GB2273143A

GB2273143A - Lock set

Info

Publication number: GB2273143A
Application number: GB9324516A
Authority: GB
Inventors: Morris Smolarski
Original assignee: Ripponlea Australia Pty Ltd
Current assignee: Ripponlea Australia Pty Ltd
Priority date: 1992-12-02
Filing date: 1993-11-30
Publication date: 1994-06-08
Anticipated expiration: 2013-11-30
Also published as: GB9324516D0; GB2273143B

Abstract

A lock set comprises a pair of face plates 25, 26 adapted to be attached to opposite faces of a door, a lock spindle 13, and a pair of ceramic knobs or handles 11, 12 each knob or handle having secured therein a sleeve 40 with an internally threaded bore, the sleeve having a laterally extending threaded internally threaded bore, the sleeve having a laterally extending threaded hole accommodating a grub screw 36 whereby in use the spindle is located across a door lock, the face plates are positioned over the projecting ends of the spindle, the knobs or handles are screwed onto the spindle to a position close to the face plates and the grub screws are tightened to prevent relative rotation of the knobs/handles and the spindle. <IMAGE>

Description

LOCK ACCESSORIES This invention relates to lock accessories and in particular to knobs and handles made of ceramic materials.

In the restoration or renovation of period style properties, there is a demand to replace modern lock fittings with fittings that reflect the period of the property. Mortise passage locks usually include a lock spindle that extends through a door to operate a mortise lock. A decorative face plate is positioned on each side of the door over the projecting end of the spindle. A knob or handle is secured to each end of the spindle to allow operation of the lock from either side of the door. It is common practice to purchase lock sets that include a pair of ornamental face plates, a spindle pair or and a pair of knobs or handles. In some cases the knobs and face plates are made of ceramics especially porcelain. Due to variations in the thickness of doors, some adjustability is required of the position of the knobs/handles on the spindle.In a correctly fitted assembly, the knobs/handles should be close to the face plates and little or no movement should take place along the axis of the spindle.

It has proved difficult to positively locate porcelain products whilst accommodating for doors of varying thicknesses. A loose fitting assembly can result in breakage of either face plate caused by a sudden impact of the knob or handle against the brittle face plate.

This invention is a result of the problems discussed above.

According to the present invention there is provided a lock set comprising a pair of face plates adapted to be attached to opposite faces of a door, a lock spindle, and a pair of ceramic knobs or handles, each knob or handle having secured therein a sleeve with an internally threaded bore, the sleeve having a laterally extending threaded hole accommodating a grub screw whereby in use the spindle is located across a door lock, the face plates are positioned over the projecting ends of the spindle, the knobs or handles are screwed onto the spindle to a position close to the face plates and the grub screws are tightened to prevent relative rotation of the knobs/handles and the spindle.

An embodiment of the present invention will now be described by way of example only with reference to the accompanying drawings in which: Figure 1 is a perspective view of part of a door showing one side of a mortise lock; Figure 2 is a partially sectioned end on view of the door showing both sides of a lock set; Figure 3 is a cross-sectional view taken along the lines 3-3 of Figure 2;and Figure 4 is an exploded perspective view of component parts of the lock set.

As shown in the accompanying drawings, a lock set for a mortise lock 10 comprises a pair of knobs 11 and 12 that are interconnected by a spindle 13 that extends through the door 20 to engage and drive a latch bolt 21 that forms part of a mortise lock. The lock itself does not form part of this invention and is thus not described in detail. The lock set also includes a pair of face plates 25 and 26 that are secured on either side of the door 20 over the projecting ends of the spindle 13. As shown in Figures 2 and 4, the spindle 13 is threaded along its length and is also provided with four elongate grooves 27 that are positioned equally spaced around the circumference of the spindle. The grooves are arranged to extend to a depth that is below the height of the threads.

The knobs or in some cases handles, although only knobs are illustrated in the drawings, are manufactured of a comparatively brittle material such as porcelain. Each knob comprises a bulbous gripping portion 31 with a forwardly projecting boss 32. The boss 32 is provided with an internal bore 30 of square cross-section as shown in Figures 3 and 4. A radial bore 34 is positioned in the boss 32 to facilitate access to a grub screw 36. The internal bore 30 of square cross-section is arranged to accommodate in a press fit a brass sleeve 40 of square cross-section with slightly rounded corners. The sleeve 40 is provided with an internal threaded bore 41 of circular cross-section. The sleeve is comparatively long and is adhesively secured within the bore 30 of the boss 32 of the knob so that the end of the sleeve is flush with the end of the boss 32.The sleeve 40 is also provided with a small threaded hole 42 in one comer and the sleeve is mounted to the boss so that the hole 42 is axially aligned with the radial bore 34 in the boss 32. The small threaded hole 42 accommodates the grub screw 36 which can be adjusted by inserting a screw driver through the radial bore 34. The threaded hole 42 for the grub screw 36 is positioned in the corner of the brass sleeve 40 because the comers are the thickest part of the sleeve and therefore there is a better opportunity to cut an internal thread on the small radial hole.

To fit the lock set, the face plates 23, 26 are positioned on either side of the door 20 and the threaded spindle 13 is centrally positioned in the door as shown in Figure 2. Each knob 11, 12 is then screwed onto the respective projecting end of the spindle 13 until the boss 32 is in close proximity to the face plate 25 or 26. The knobs 11, 12 are screwed onto the spindle 13 to ensure that there is little or no movement of the assembly in the direction parallel to the axis of the spindle 13. When the knobs 11, 12 have been positioned on the ends of the spindle, the grub screws 36 are adjusted to engage one of the longitudinal grooves 27 in the spindle 13 and to prevent rotation ofthe knobs 25, 26 relative to the spindle 13. The grub screw 36 thus locks the assembly in the selected position.

It has been discovered that this assembly provides positive location of the knobs on the spindle so that longitudinal movement of the assembly is kept to a minimum thus avoiding the danger of damage to the face plates caused by sudden impact forces being placed on either handle causing longitudinal displacement of the knob towards and against the face plate; In a situation where the face plate is made out of ornate porcelain, a sudden blow by the boss of the handle frequently causes the face plate to disintegrate.

The combination of the threaded sleeve in the internal bore of the knob allows the lock set to fit a variety of doors of different thicknesses.

Although the preferred embodiment is used in conjunction with elongate rectangular face plates, it is understood that the assembly operates equally as well with other types of face plate such as those of circular configuration.

Claims

1. A lock set comprising a pair of face plates adapted to be attached to opposite faces of a door, a lock spindle, and a pair of ceramic knobs or handles, each knob or handle having secured therein a sleeve with an internally threaded bore, the sleeve having a laterally extending threaded hole accommodating a grub screw whereby in use the spindle is located across a door lock, the face plates are positioned over the projecting ends of the spindle, the knobs or handles are screwed onto the spindle to a position close to the face plates and the grub screws are tightened to prevent relative rotation of the knobs/handles and the spindle.

2. The lock set according to Claim 1 wherein the sleeve is of square cross-section and is adhesively secured within a corresponding profiled bore within the knob or handle.

3. The lock set according to Claim 2 wherein the laterally extending threaded hole accommodating a grub screw is positioned in one corner of the sleeve.

4. The lock set according to any one of the preceding claims wherein the spindle is provided with at least one longitudinally extending groove adapted to accommodate the projecting end of the grub screw.

5. The lock set according to Claim 4 wherein the spindle is provided with four longitudinally extending grooves equally positioned around the cross section of the spindle.

6. The lock set according to any one of the preceding claims wherein the knobs/handles and face plates are made of porcelain and the sleeve is made of brass.

7. A door handle or knob comprising a ceramic body having an internal bore adapted to fixedly support a sleeve having an internally threaded bore, the internally threaded bore having a small transversely extending threaded hole containing a grub screw accessible from the exterior of the knob or handle.

8. A lock set substantially as described herein with reference to and as illustrated in the accompanying drawings.