Cylinder lock having improved torsional strength

Abstract

A cylinder lock includes a latch retractor housing having inner and outer cover plates, inner and outer drive spindles extending respectively through the inner and outer cover plates, a sleeve surrounding the outer drive spindle and having a flange contacting the outer cover plate, an outer shell surrounding the inner drive spindle and the latch retractor housing, and at least one rigid coupling member or tube disposed within the outer shell and engaging and coupling together the inner and outer cover plates and the flange, thereby reinforcing the outer drive spindle and the latch retractor housing and increasing torsional and compression strengths thereof. A reinforcing ring is further provided to couple the outer drive spindle to the outer handle for reinforcement.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiment with reference to the accompanying drawings, of which:

FIG. 1 is an exploded view of a cylinder lock embodying the present invention;

FIG. 2 is an exploded view showing all component parts of a drive mechanism of the cylinder lock in an unassembled state;

FIG. 3 is another exploded view showing the unassembled component parts of the drive mechanism except inner and outer drive spindles and a latch retractor;

FIG. 4 is a partly exploded view showing that all parts of the drive mechanism are assembled together except an outer shell of the drive mechanism;

FIG. 5 is an exploded perspective view showing an outer handle, an outer drive spindle and a reinforcing ring;

FIG. 6 is a perspective view showing the components of FIG. 5 in an assembled state.

Claims

1. A cylinder lock comprising: a latch retractor adapted to be connected to a latch;a latch retractor housing receiving said latch retractor and having an inner cover plate;inner and outer drive spindles extending into said latch retractor housing to operate said latch retractor, said inner drive spindle extending through said inner cover plate;a sleeve connected to said latch retractor housing and surrounding said outer drive spindle, said sleeve having a flange projecting radially from said sleeve and opposite to said inner cover plate;an outer shell surrounding said inner drive spindle and associated with said sleeve to encase said latch retractor housing; andat least one rigid coupling member disposed within said outer shell and engaging said inner cover plate and said flange, said rigid coupling member being offset from and being substantially parallel to a rotation axis of said inner and outer drive spindles.

2. The cylinder lock of claim 1, wherein said latch retractor housing further has an outer cover plate opposite to said inner cover plate and contacting said flange, said outer drive spindle extending through said outer cover plate, said inner and outer cover plates and said flange being respectively provided with edge notches that are aligned with each other axially, said rigid coupling member engaging said aligned edge notches.

3. The cylinder lock of claim 2, wherein said rigid coupling member is formed as a tube engaging said aligned edge notches.

4. The cylinder lock of claim 3, wherein said tube further has two opposite ends respectively formed with two circumferentially extending first and second slots, said first slot engaging one of said edge notches formed in said inner cover plate, said second slot engaging said edge notches respectively formed in said outer cover plate and said flange.

5. The cylinder lock of claim 4, wherein a pair of said tubes are provided at two diametrically opposite positions.

6. The cylinder lock of claim 4, wherein said outer shell has a large tubular part encasing said latch retractor housing, a small tubular part surrounding said inner drive spindle, and a shoulder plate disposed between said large and small tubular parts, said tube extending to said shoulder plate and further having an internal thread, said rigid coupling member further having a screw passing through said shoulder plate and engaging said internal thread.

7. The cylinder lock of claim 6, wherein said latch retractor housing further has upper and lower plates bridging said inner and outer cover plates, each of said upper and lower plates having one end extending through said inner cover plate and engaging said shoulder plate, and another end extending through said outer cover plate and engaging said flange.

8. The cylinder lock of claim 1, further comprising an outer handle having a tubular end portion sleeved onto a portion of said outer drive spindle, and a reinforcing ring extending around another portion of said outer drive spindle to reinforce said outer drive spindle, said reinforcing ring having two opposite ends respectively engaging said tubular end portion and said another portion of said outer drive spindle.

9. A cylinder lock of claim 8, wherein said another end portion of said outer drive spindle has two diametrically opposite first protrusions extending radially from said another portion, said reinforcing ring further having two diametrically opposite first cutouts engaging said first protrusions, respectively.

10. The cylinder lock of claim 9, wherein said another end portion of said outer drive spindle further has a second protrusion projecting radially from said another portion between said first protrusions, said reinforcing ring further having a second cutout engaging said second protrusion.

11. The cylinder lock of claim 9, wherein said tubular end portion of said outer handle has two diametrically opposite third cutouts, said reinforcing ring further having two diametrically opposite fingers that project axially from said reinforcing ring and that engage said third cutouts, respectively.

12. A cylinder lock having a drive mechanism, comprising: an outer handle having a tubular end portion;an outer drive spindle connected to said tubular end portion and adapted to transmit a torque from said outer handle to the drive mechanism, said outer drive spindle having a portion inserted into said tubular end portion;a reinforcing ring sleeved around another portion of said outer drive spindle and having two opposite ends respectively engaging said tubular end portion and said another portion of said outer drive spindle.

13. A cylinder lock of claim 12, wherein said another end portion of said outer drive spindle has two diametrically opposite first protrusions extending radially from said another portion, said reinforcing ring further having two diametrically opposite first cutouts engaging said first protrusions, respectively.

14. The cylinder lock of claim 13, wherein said another end portion of said outer drive spindle further has a second protrusion projecting radially from said another portion between said first protrusions, said reinforcing ring further having a second cutout engaging said second protrusion.

15. The cylinder lock of claim 13, wherein said tubular end portion of said outer handle has two diametrically opposite third cutouts, said reinforcing ring further having two diametrically opposite fingers that project axially from said reinforcing ring and that engage said third cutouts, respectively.