The present invention relates to an electrical connector for detachable connection to a battery pack or cassette type electronic package.
Figure 5 shows an example of a known connector for achieving an electrical connection to a battery pack. Referring to Figure 5, the known structure includes a contact member 10' including contact portion 11' for making and electrical contact with an electrode 41' of a battery pack 40'. A connecting portion 12' retains a wire 30' soldered thereto, and a fixing portion 13' (anchoring portion) for fixing, for example, by caulking the contact member to the body of a housing or terminal base 20'.
Fixing of the contact member to the main part by caulking is not only troublesome but is also extremely complicated since the caulking force has to be controlled considering its state after caulking, e.g., a state in which the contact member may rotate to the left or right but is fixed without any play against vertical movement.
DE-A-1765922 discloses a connector in which contacts are secured to a housing without caulking. DE-A-1765922 discloses a connector for connecting to a battery comprising a plurality of contact members and a housing mounting the contact members, each contact member including a contact portion for electrically connecting to a battery electrode, a connecting portion for connecting a wire member thereto, a fixing portion interconnecting the contact portion and the interconnecting portion and fixing the contact member to the housing, the fixing portion having an inverse U-shaped cross section with an opposing pair of side walls and an engaging arm extending therefrom towards the contact portion, the housing including recesses for receiving and holding the fixing portions of the contact members and an engaging portion for engaging with the engaging arms of the contact members.
In DE-A-1765922, the fixing portion with an inverse U-shaped cross section has flanges which extend outwardly from the free edges of the opposing side walls. Securement of a contact in the housing is achieved by inserting the flanges in the recesses, pressing the flanges beneath lips formed over part of the recesses and sliding the flanges under the lips until the engaging arm can locate in a recess (engaging portion) to lock the fixing portion in place.
This complex sliding and pressing movement combination presents a drawback, and connectors according to the invention aim to overcome this problem by providing a connector with contacts which can be secured in place simply by pressing the contact member into the housing, and without the need for caulking.
To this end, according to the present invention, there is provided a connector for connecting to a battery, comprising: a plurality of contact members and a housing mounting said contact members, each said contact member including a contact portion for electrically connecting to a battery electrode, a connecting portion for connecting a wire member thereto, and a fixing portion interconnecting said contact portion and said connecting portion and fixing said contact member to said housing, said fixing portion having an inverse U-shaped cross-section with opposing pair of side walls and an engaging arm extending therefrom towards said contact portion, each said side wall having an aperture, said housing including a recess for receiving and holding said fixing portions of said contact members and an engaging portion for engaging with said engaging arms of said contact members, inner wall surfaces of said recess having projections which engage with said openings in said fixing portions of said contact members.
By way of example, one embodiment of an electrical connector will now be described with reference to the accompanying drawings, in which:-
Each contact member 10 has a contact portion 11 which also serves as a leaf spring, a connecting portion 12 for connection to a wire 30, and a fixing portion 13 which interconnects the contact portion and the connecting portion and fixes the contact portion to the housing. In the illustrated embodiment, the contact portion 11 is disposed so as to be exposed externally.
The contact portion 11 projects into a cavity for receiving the battery pack and connects an electrode exposed on the bottom of the battery case in the cavity for electrical contact therewith.
Referring to Figures 2 and 3, the fixing portion 13 has a main part composed of a pair of opposing side walls 13A which define an inverse U-shaped cross-section and an engaging arm 13B which extends downward from the main part towards the contact portion. Each side wall 13A of the fixing portion 13A has an opening 13C.
The housing 20 includes a recess 21 for receiving and holding the fixing portion of each contact and an engaging portion 22 for engaging with the engaging arm 13B of the contact member. In the illustration, the engaging portion 22 of the housing has a tapered wall surface 22A. Projections 21A, for engaging with the openings in the fixing portion of the contact members, are formed in the inner wall surfaces of the recess 21.
Figure 4 illustrates the manner in which the contact portion 11 contacts an electrode 41 of the battery pack. The arrangement is such that, when the battery pack is mounted on a device, the electrode 41 presses the contact portion 11 of the contact so as to be held in contact therewith as illustrated.
For mounting the contact member 10 in accordance with the present invention, the pair of opposing side walls 13A of the fixing portion 13 of the contact member is fitted in the recess 21 of the housing. In this state, the projections 21A on the inner wall surface engage with the openings 13A in the side walls. Since the side walls tend to expand outward, the fixing portion of the contact member are fixed and held in the recess of the housing. At the same time, the engaging arms 13B engage with a step which is presented by the tapered wall surface 22A of the engaging portion of the housing.
As has been described, the connecting structure in accordance with the present invention, makes it possible to securely mount the fixing portion of the contact member in a recess of a housing simply by pressing the contact member into the housing, without requiring caulking, by virtue of the specific structure of the contact member and the housing, thus significantly improving the mounting efficiency of the contact member.
Having described the preferred embodiment herein, it should be appreciated that variations may be made thereto without departing from the contemplated scope of the invention. Accordingly, the preferred embodiment described herein is illustrative and not limiting, the true scope of the invention being set forth in the claims appended hereto.