The present invention relates to a connector used for connecting a flat cable and, in particular, relates to a structure for retaining the flat cable by the connector.

A connector used for connecting a flat cable is disclosed in, for example, EP1003245. This connector comprises a contact-side insulator retaining conductive contacts, and a cable-side insulator retaining a flat cable. The cable-side insulator is attachable/detachable relative to the contact-side insulator. When the cable-side insulator is attached to the contact-side insulator, wires of the flat cable are brought into pressure contact with the contacts. In this manner, the flat cable is connected to the connector.

In the connector of this type, it is necessary that the contacts and the flat cable are securely fixed/retained relative to the contact-side insulator and the cable-side insulator, respectively. The contacts can be retained relatively easily by providing mutual engagement structures between the contact-side insulator and the contacts. For example, by optionally contriving a shape of contacts, it is possible to engage the contacts with the contact-side insulator.

On the other hand, since the flat cable has a standardized simple shape as is well known, it is relatively difficult to retain it relative to the cable-side insulator. Movement of the flat cable relative to the cable-side insulator impedes the pressure-contact contention between the wires of the flat cable and the contacts, and thus should be avoided. EP1003245 disloses upper and lower cover insulators clamping upper and lower coaxial cables in recesses of the upper and lower cover insulators by a spacer.

According to those conventional techniques, however, the retention of the flat cable relative to the cable-side insulator is insufficient. Further, complicated facilities are required for automating assembly of the connector, which thus raises a problem also in terms of economics.

It is therefore an object of the present invention to provide a connector for a flat cable, which can securely retain the flat cable and economically cope with automation of assembly.

According to the present invention, there is obtained a system for forming a flat cable connector capable of connecting one or two flat cables according to claim 1,

The first insulator may have a guide groove for guiding the cable-side insulator to be attached/detached, and the second and third insulators may have convex portions, respectively, which are inserted into the guide groove.

The second insulator may have a concave portion confronting the clamp, and the flat cable may be pushed into the concave portion by the clamp.

The flat cable may comprise a plurality of cable elements, and the second insulator and the clamp may have a function of conjointly arraying the cable elements.

The third insulator may be an integral body.

The flat cable may be formed with a generally crank-shaped convex portion, and the convex portion may be received in the concave portion of the second insulator.

• Fig. 1 shows a connector according to a first embodiment of the present invention, wherein (a) shows a bottom view, (b) shows a left side view (a diagram seen from a fitting side with a counterpart connector), (c) shows a front view, (d) shows a right side view, and (e) shows a rear view, respectively.
• Fig. 2 is a sectional view taken along line II-II in Fig. 1(c).
• Fig. 3 is a sectional view taken along line III-III in Fig. 2.
• Fig. 4 is a sectional view, like Fig. 2, of a connector according to a second embodiment of the present invention.
• Fig. 5 is a sectional view taken along line V-V in Fig. 4.

Referring to Figs. 1 to 3, description will be made of a connector according to a first embodiment of the present invention.

The connector of Figs. 1 to 3 is used for connecting one flat cable 6 such as a flat ribbon cable, and comprises a first insulator 1, a second insulator 2, and a third insulator 3. In Figs. 1 (a) and 2, the first insulator 1 is disposed on the left side, the second insulator 2 is disposed roughly on the lower right side, and the third insulator 3 is disposed roughly on the upper right side. These insulators 1, 2, and 3 are fitted together according to a later-described structure to form an insulator portion of the connector.

The first insulator 1 fixedly retains first conductive contacts 4 divided into an upper side and a lower side and confronting each other in a vertical direction. The first contacts 4 are arrayed in large numbers on the upper side and the lower side, respectively.

Each of the first contacts 4 comprises a contact portion 4a for obtaining electrical connection to a counterpart connector, and a generally U-shaped tuning fork portion 4b. Inside the tuning fork portion 4b, connecting portions 4c are projectingly formed. The contact portions 4a of the first contacts 4 are arranged in an opening portion 1a of the first insulator 1 so as to confront each other in the vertical direction. The first insulator 1 forms a contact-side insulator.

The second insulator 2 fixedly retains second conductive contacts 5. The second contacts 5 are arrayed corresponding to the first contacts 4 on the lower side. The second insulator 2 is formed with a concave portion 2a having a generally trapezoidal shape in section and confronting the third insulator 3. The concave portion 2a is formed with two confronting portions 8.

The flat cable 6 is disposed between the second and third insulators 2 and 3. Thereupon, a generally crank-shaped portion defined by a convex portion 6a and a concave portion 6b formed in the flat cable 6 is disposed in the concave portion 2a of the second insulator 2.

The connector of Figs. 1 to 3 further comprises an insulating clamp 7 interposed between the third insulator 3 and the flat cable 6. The clamp 7 has a portion 7a having a generally trapezoidal shape in section and confronting the concave portion 2a of the second insulator 2. The generally crank-shaped portion of the flat cable 6 is sandwiched between the portion 7a having the generally trapezoidal shape in section and the confronting portions 8. The second and third insulators 2 and 3 conjointly form a cable-side insulator.

Projecting portions 7c are formed on both left and right sides of the clamp 7. Holes 2b are formed at both left and right side portions of the second insulator 2. Rails 2c are formed on both left and right side surfaces of the second insulator 2. The third insulator 3 is formed with several ribs 3a. Rails 3b are formed on both left and right side surfaces of the third insulator 3. The first insulator 1 is formed with grooves 1 b. Incidentally, wires 6c are each bent into a shape approximate to a predetermined U-shape in advance.

The projecting portions 7c of the clamp 7 are inserted into the holes 2b of the second insulator 2 in the state where the flat cable 6 is sandwiched as described above. The ribs 3a of the third insulator 3 and the rails 3b of the third insulator 3 are mounted on an upper surface of the clamp 7 and upper surfaces of the rails 2c of the second insulator 2.

Further, each rail 2c of the second insulator 2 and each rail 3b of the third insulator 3 are fitted into the groove 1b of the first insulator 1, then the first insulator 1 is slided relative to the second and third insulators 2 and 3. Then, by fitting between the rails 2c and 3b and the grooves 1b, the second and third insulators 2 and 3 are engaged with the first insulator 1 in the vertical direction so as to approach each other. As a result, the flat cable 6 is firmly sandwiched between the second insulator 2 and the clamp 7.

Further, when the first insulator 1 is slided relative to the second and third insulators 2 and 3, the wires 6c at the tip of the flat cable 6 are each sandwiched between the tuning fork portion 4b and a tip portion 5a of the second contact 5 so as to be reformed into the predetermined U-shape. As a result, the wires 6c of the flat cable 6 and the connecting portions 4c of the first contacts 4 suitably contact with each other to be electrically connected. Incidentally, as shown in Fig. 1, the first insulator 1, the second insulator 2, and the third insulator 3 are fixed together by inserting anti-release pins 9 into through holes that are formed at upper and lower two portions, respectively.

In Fig. 2, when the flat cable 6 is pulled rightward, the clamp 7 is pushed by the concave portion 6b of the flat cable 6 so as to attempt to move upward. However, as shown in Fig. 3, the several ribs 3a of the third insulator 3 prevent upward movement (rise) of the clamp 7. Therefore, the flat cable 6 is firmly retained by the connector so that pulling-out thereof is prevented.

Referring to Figs. 4, and 5, description will be made of a connector according to a second embodiment of the present invention. Like portions are assigned the same reference symbols so that description thereof may be omitted. Those portions of which description is omitted have the same structures as the connector of Figs. 1 to 3.

The connector of Figs. 4 and 5 is used when connecting two flat cables 6 one over the other. In this case, use is made of an insulating additional clamp 7" having the same shape and size as the clamp 7 in the connector of Figs. 1 to 3. That is, use is made of two insulators and two clamps that are the same as the second insulator 2 and the clamp 7 in the connector of Figs. 1 to 3. Therefore, the additional clamp 7" also has a portion 7a" having a generally trapezoidal shape in section and fitted in a concave portion 2a' of an additional insulator 2'.

The additional insulator 2' also fixedly retains second contacts 5. The second contacts 5 of the additional insulator 2' are arrayed corresponding to the first contacts 4 on the upper side. The additional insulator 2' is formed with the concave portion 2a' having a generally trapezoidal shape in section. The concave portion 2a' is formed with confronting portions 8'.

Projecting portions 7c" are formed on both left and right sides of the additional clamp 7". Holes 2b' are formed at both left and right side portions of the additional insulator 2'. Rails 2c' are formed on both left and right side surfaces of the additional insulator 2'.

The flat cable is disposed between the second insulator 2 and the clamp 7, and besides, the flat cable 6 is disposed also between the additional insulator 2' and the additional clamp 7". Thereupon, a generally crank-shaped portion defined by a convex portion 6a and a concave portion 6b formed in the flat cable 6 is disposed in the concave portion 2a' of the additional insulator 2'.

When the second insulator 2 and the additional insulator 2' are mounted to the first insulator 1 following fitting between the rails 2c and 2c' and the grooves 1b, the additional insulator 2' along with the second insulator 2 is engaged with the first insulator 1 in the vertical direction to approach each other, according to the structure like the connector of Figs. 1 to 3. As a result, the flat cable 6 is firmly sandwiched between the second insulator 2 and the clamp 7, and besides, the flat cable 6 is firmly sandwiched also between the additional insulator 2' and the additional clamp 7".

Incidentally, when connecting one flat cable in the connector of Figs. 4 and 5, the additional insulator 2' and the additional clamp 7" may be replaced with the third insulator 3 in the connector of Figs. 1 to 3. In this manner, it is possible to easily carry out connection of one flat cable or connection of two flat cables by exchanging the components.

The connector for a flat cable of the present invention is suitable as a connection device for a flat cable used in a computer, a portable telephone, or the like.