CROSS-REFERENCES TO RELATED APPLICATION

Relevant subject matter is disclosed in the co-pending U.S. patent application Ser. No. 11/309,706, filed on Sep. 15, 2006, and entitled â€œLATCH MECHANISM FOR FOLDABLE ELECTRONIC DEVICEâ€ , which is assigned to the same assignee with this patent application.

FIELD OF THE INVENTION

The present invention relates to a latch mechanism, and more particularly to a latch mechanism for a portable computer.

DESCRIPTION OF RELATED ART

Typically, an electronic device, such as a portable computer, includes a cover unit and a base unit pivotally connected with the cover unit, and a latch mechanism is provided to lock the cover unit to the base unit.

As disclosed in U.S. Pat. No. 6,115,239, a latch mechanism for locking a cover unit to a base unit, includes a latch frame movably installed inside the cover unit, a plurality of latches are formed on the latch frame at predetermined intervals and one end portion of each latch protrudes from a front surface of the cover unit, and a slide knob is operatively connected to the latch frame for concurrently operating the latches. The latches are inserted into and locked by latch grooves formed at positions corresponding to the latches on an upper surface of the base unit. The latches are urged against the base unit by elastic forces applied by double springs mounted on two ends of the latch frame. However, to open the cover unit, the slide knob is slid to overcome the elastic forces of the springs to move the latch mechanism for disengaging from the base unit. The slide force depends on friction between the slide knob and fingers of an operator. It is laborious for an operator to provide enough force to move a slide knob.

What is needed, therefore, is a laborsaving latch mechanism.

SUMMARY OF THE INVENTION

An exemplary latch mechanism includes a latching member, a button, and an elastic member for restoring the latching member. The latching member is rotatably installed in a cover unit. The latching member includes a latching portion for engaging with a base unit. The button is movably fixed to the cover unit. The button includes a slanted pushing portion for driving the latching member to rotate for disengaging the latching portion from the base unit.

Other advantages and novel features will become more apparent from the following detailed description of a preferred embodiment when taken in conjunction with the accompanying drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded, isometric, inverted view of a latch mechanism with a cover unit in accordance with a preferred embodiment of the present invention, and the cover unit includes a first panel and a second panel;

FIG. 2 an enlarged, assembled view of FIG. 1 without the first panel of the cover unit;

FIG. 3 is an assembled view of FIG. 1;

FIG. 4 is a cross-sectional view taken along line IV-IV of FIG. 3;

FIG. 5 is similar to FIG. 4, but showing another state of the latch mechanism; and

FIG. 6 is a schematic, assembled view of FIG. 1 with a base unit.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIGS. 1 to 3, a latch mechanism is provided in accordance with a preferred embodiment of the present invention, for locking a cover unit 10 to a base unit 50 (as shown in FIG. 6) of an electronic device, such as a portable computer. The latch mechanism includes a button 20, a latching member 30, and a pair of elastic members 40. In this embodiment, the elastic members 40 are torsion springs.

The cover unit 10 includes a first panel 11, and a second panel 13 having a pair of through holes 137 defined therein. The second panel 13 holds a liquid crystal display therein. A cutout 131 is defined in the middle of a front edge of the second panel 13, and an inverted T-shaped receiving portion 132 is formed on an inside surface of the second panel 13 communicating with the cutout 131. A stop plate 134 having an aperture 1342 defined therein is perpendicularly formed on a middle section of the receiving portion 132, and parallel to the front edge of the second panel 13. Two spaced hooks 135 are formed on the receiving portion 132 adjacent to two lateral ends of the stop plate 134 respectively. A plurality of pairs of fixing members 136 are formed on the second panel 13 behind the receiving portion 132, and are arranged in a line parallel to the front edge of the second panel 13. Each of the fixing members 136 defines a curved groove 1362, and the grooves 1362 of each pair of the fixing members 136 are opposite to each other. Two spaced fixing plates 138 and two staggered hooking members 139 are formed on the inside surface of the second panel 13 behind the receiving portion 132.

The button 20 includes a pressing portion 22, and two spaced arms 24 extending perpendicularly from a rear end of the pressing portion 22. Two protrusions 23 extend from two lateral ends of the pressing portion 22 respectively. A slanted pushing portion 25 extends from a free end of each arm 24, and a post 26 protrudes from the rear end of the pressing portion 22 between the arms 24.

The latching member 30 includes a main body 31. A pair of latching portions 32 extends down from the main body 31 adjacent to two opposite ends thereof, and each latching portion 32 defines a latching hole 33 from a front portion thereof. Two spaced recesses 34 are defined in a top portion of the main body 31, corresponding to the fixing plates 138 of the second panel 13. A rod 35 extends from the main body 32 in each recess 34. A projection 36 is formed on a front surface of the main body 31 adjacent to each recess 34. A plurality of arcuate flanges 37 is formed on the front surface and a rear surface of the main body 31, corresponding to the grooves 1362 of the fixing members 136 of the second panel 13. Two notches 38 are defined from the top portion to the front surface and the rear surface of the main body 31 respectively, for engaging with the hooking members 139 of the second panel 13 respectively.

Referring further to FIG. 6, the base unit 50 defines a pair of latching slots 51, corresponding to the latching portions 32 of the latching member 30. A slanted block 53 extends into each latching slot 51 from the base unit 50.

Referring also to FIG. 2, in assembly, the latching portions 32 extend through the through holes 137 from the inside surface of the second panel 13. The flanges 37 of the latching member 30 rotatably engage with the grooves 1362 of the fixing members 136 of the second panel 13 respectively, and the hooking members 139 of the second panel 13 engage in the notches 39 of the latching member 30 respectively. After that, the elastic members 40 are placed around the rods 35 adjoining the corresponding recesses 34 of the latching member 30 respectively. One end of each elastic member 40 is fixed to the corresponding projection 36 of the latching member 30, and the other end of each elastic member 40 is fixed to the corresponding fixing plate 138 of the second panel 13. Thereby, the latching member 30 is rotatably mounted on the second panel 13.

An elastic member 28 is placed around the post 26 of the button 20. The button 20 is placed on the receiving portion 132 of the second panel 13, with a free end of the post 26 extending through the aperture 1342 of the stop plate 134 of the second panel 13, the hooks 135 of the second panel 13 engaging with the arms 24 and abutting against the pushing portions 25 of the button 20. The protrusions 23 of the pressing portion 22 of the button 20 abut against the front edge of the second panel 13, and the pressing portion 22 is exposed in the cutout 131 of the second panel 13. Thereby, the button 20 is slidably mounted on the second panel 13. In this embodiment, the elastic member 28 is a coil spring.

Referring also to FIG. 3, the first panel 11 is fixed to the second panel 13 to cover one side of the liquid crystal display, thereby the cover unit 10 is fully assembled.

Referring to FIGS. 4 to 6, the cover unit 10 is pivotably attached to the base unit 50. The cover unit 10 is pivoted to cover the base unit 50 when the electronic device is not in use. The latching portions 32 enter the corresponding latching slots 51 of the base unit 50, and bottom surfaces of the latching portions 32 abut against the blocks 53 in the latching slots 51 respectively. The cover unit 10 is further pressed down, the latching portions 32 are pushed backward, and the main body 31 of the latching member 30 is therefore pushed to deform the elastic members 40 and rotate away from a front edge of the cover unit 10 until the blocks 53 of the base unit 50 align with the latching holes 33 of the latching portions 32 respectively. The elastic members 40 are then restored to push the latching member 30 to rotate toward the front edge of the cover unit 10, and the latching portions 32 are therefore rotated toward the blocks 53 and receive the corresponding blocks 53 in the latching holes 33 thereof. Thus, the cover unit 10 is locked to the base unit 50.

Referring further to FIG. 5, to unlock the cover unit 10 from the base unit 50, the pressing portion 22 of the button 20 is pressed to compress the elastic member 28. The pushing portion 25 of the button 20 pushes a bottom portion of the main body 31 of the latching member 30 inward. The main body 31 of the latching member 30 is rotated away from the front edge of the cover unit 10, and the latching portions 32 are rotated inward to disengage from the blocks 53 of the base unit 50 respectively. Thereby, cover unit 10 is ready to be pivoted open.

It is believed that the present embodiment and its advantages will be understood from the foregoing description, and it will be apparent that various changes may be made thereto without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the example hereinbefore described merely being preferred or exemplary embodiment of the invention.