Eyeglasses comprising frame unit and snap fitted lens unit

A pair of eyeglasses includes a frame unit and a lens unit. The frame unit has a downwardly flaring projection protruding integrally and downwardly from a middle portion thereof, and two constricted slots which are located on two sides of the projection and which have inner end portions that are adjacent to the projection. The lens unit has two upwardly flaring upper portions which define a constricted hole therebetween and which are snap fitted respectively within the constricted slots of the frame unit so that the projection of the frame unit is snap fitted within the constricted hole of the lens unit, thereby retaining the lens unit on the frame unit. The engagement of the projection of the middle portion of the frame unit within the constricted hole in the lens unit facilitates firm connection of the lens unit and the frame unit.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to a pair of eyeglasses, and more particularly to a 
pair of eyeglasses including a frame unit and a lens unit which has an 
upper portion snap fitted within the frame unit. 
2. Description of the Related Art 
Referring to FIGS. 1, 2 and 3, a pair of conventional sunglasses 1 is shown 
to include a frame unit 2, a lens unit 3 and a generally inverted U-shaped 
nose bridge unit 4. The frame unit 2 has an elongated front frame 5 
coupled to two temples 7 by bolts 6, and a lens-retaining slot 8 in which 
the upper portion of the lens unit 3 is confined. The nose bridge unit 4 
consists of a nose support 10 and a nose pad 11 which is attached to the 
nose support 10. The nose support 10 has a slot 12 in which a middle 
portion 9 of the lens unit 3 is inserted tightly. The lens-retaining slot 
8 of the frame unit 2 has two generally triangular end portions 13 in 
which two triangular projections 14 of the lens unit 3 are engaged within, 
thereby preventing the removal of the lens unit 3 from the frame unit 2. 
The conventional sunglasses 1 suffers from the following disadvantages: 
(1) Upon mounting the lens unit 3 on the frame unit 2, because the 
triangular projections 14 are sharp and have a relatively large area, it 
is difficult and energy-consuming to insert the triangular projections 14 
into the triangular end portions 13 of the lens-retaining slot 8. 
Furthermore, the tips 15 of the triangular projections 14 are easily 
broken during the mounting operation. 
(2) The untimely removal of the middle portion 9 of the lens unit 3 from 
the frame unit 2 easily occurs due to the fact that it is remote (far) 
from the triangular end portions 13 of the slot 8 in the frame unit 2, 
thereby resulting in an unstable connection. 
SUMMARY OF THE INVENTION 
The object of this invention is to provide a pair of eyeglasses with a 
frame unit and a lens unit which are connected firmly to each other and 
which can be easily and conveniently assembled and removed from each 
other. 
According to this invention, a pair of eyeglasses has a frame unit and a 
lens unit. The frame unit has a downwardly flaring projection protruding 
integrally and downwardly from a middle portion thereof, and two 
constricted slots which are located on two sides of the projection and 
which have inner end portions that are adjacent to the projection. The 
lens unit has two upwardly flaring upper portions which define a 
constricted hole or gap therebetween, and which are snap fitted 
respectively within the constricted slots of the frame unit so that the 
projection of the frame unit is snap fitted within the constricted hole of 
the lens unit, thereby retaining the lens unit on the frame unit. The 
engagement of the projection of the middle portion of the frame unit 
within the constricted hole in the lens unit facilitates firm connection 
of the lens unit and the frame unit.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to FIGS. 4, 5, 6 and 7, the preferred embodiment of a pair of 
eyeglasses according to this invention is shown to include a frame unit 
20, a unitary lens unit 30 and a unitary nose pad 40. 
The frame unit 20 has a front frame 21, two temples 23 connected 
respectively to two ends of the front frame 21 by means of bolts 22, and a 
generally inverted Y-shaped nose support 24. The front frame 21 has two 
constricted slots 25 which are formed along a bottom surface thereof, and 
a downwardly flaring projection 26 protruding integrally and downwardly 
from a middle portion of the front frame 21 and located between the 
constricted slots 25. The projection 26 has two opposite sides which 
define two generally triangular inner end portions 251 of the constricted 
slots 25. Each of the constricted slots 25 has a curved outer end portion 
252. The nose support 24 has four integral pins 241 and a generally planar 
front face 242. 
The lens unit 30 has two aligned upwardly flaring upper portions 31 which 
define a constricted hole 32 therebetween and which are snap fitted 
respectively within the constricted slots 25 of the frame unit 20. At this 
time, the projection 26 of the frame unit 20 is snap fitted within the 
constricted hole 32 of the lens unit 30, thereby retaining the lens unit 
30 on the frame unit 20. As illustrated, the lens unit 30 has two 
generally triangular projections 33 engaged within the generally 
triangular inner end portions 251 of the constricted slot 25 of the frame 
unit 20, and two curved projections 34 engaged within the curved outer end 
portions 252 of the constricted slot 25 of the frame unit 20. A rear 
surface of the lens unit 30 abuts against the front face 242 of the nose 
support 24 of the frame unit 20 for positioning the lens unit 30 relative 
to the frame unit 20. 
The nose pad 40 is generally inverted U-shaped and has a front surface 
formed with four pin holes 41 for insertion of the pins 241 of the nose 
support 24 in order to attach the nose pad 40 to the nose support 23. 
Because the projections 34 are curved but not sharp, the upper portions 31 
of the lens unit 30 can be easily inserted into the constricted slots 25 
of the frame unit 20. In this way, breaking of the projections 34 can be 
avoided. Most importantly, the engagement of the projection 26 of the 
frame unit 20 within the constricted hole 32 of the lens unit 30 
facilitates firm connection between the frame unit 20 and the lens unit 
30. In other words, removal of the lens unit 30 from the frame unit 20 can 
be prevented. 
With this invention thus explained, it is apparent that numerous 
modifications and variations can be made without departing from the spirit 
and scope of this invention. It is therefore intended that this invention 
be limited only as indicated in the appended claims.