Patent Description:
As an electric connector fixed to a panel of a casing, an electric connector having a plurality of fitting ports to and from which cable connectors are connected and disconnected is known (for example, refer to patent literature <NUM> (<CIT>)). The electric connector disclosed in patent literature <NUM> includes a housing having a cylindrical housing main body in which fitting ports are formed side by side and a pair of fixed parts protruding from the side face of the housing main body. A panel of the casing has an attachment hole into which a case part is insertable. In a state where the case part is inserted into the attachment hole from an inside of the casing and the case part is protruded from the outer face of the panel, the electric connector is fastened to the inner face of the panel via the pair of fixed parts using screws. <CIT> describes a rubber stopper <NUM> mounted in the accommodating concave portion <NUM> of the housing main body <NUM>. However, the rubber stopper <NUM> does not seal between the peripheral wall of the accommodating concave portion <NUM> and the mating connector housing. The rubber stopper <NUM> seals between the terminal fitting <NUM> connected to the housing main body <NUM> and the peripheral wall of the accommodating concave portion <NUM>. Since the front member <NUM> for extraction is attached to the front of the rubber stopper <NUM>, the mating connector housing does not come into contact with the rubber stopper <NUM> when the mating connector housing is attached to the connector housing <NUM>. <CIT> describes an electric connector which is configured to be connected to a plurality of counter cable connectors, said connector is provided with a housing configured to be attached to an attachment hole of a panel of a casing, wherein the housing includes a housing main body configured to be inserted into the attachment hole of the panel and a flange part extending outward from an outer circumferential face of the housing main body. The housing main body has a plurality of fitting port into which the plurality of counter cable connectors is configured to be fitted, on an outside of the casing, wherein a first water-proof seal which is configured to prevent infiltration of moisture into the inside of the casing along inner faces of the fitting ports is installed to each of the fitting ports, the first water-proof seal is configured to seal between a circumferential wall of each of the fitting ports and each of the counter cable connectors.

By the way, such an electric connector is sometimes attached to a portion where a high water-proof performance is required. Although the above described electric connector does not require to be prepared individually for each cable connector and allows space saving, there is a problem in which infiltration of moisture into the inside of the casing is not sufficiently prevented.

The present invention is made in the above described view and it is therefore an object of the present invention to provide an electric connector of preventing infiltration of moisture into the inside of the casing and achieving space saving.

To achieve the object, an electric connector of one aspect of the present invention is an electric connector according to claim <NUM>. According to another aspect of the invention an assembly comprising the electric connector according to claim <NUM> and the plurality of counter cable connectors is provided according to claim <NUM>.

An electric connector of one aspect of the present invention is fixed to the panel via the flange part in a state where the housing main body is inserted into the attachment hole of the panel and the housing main body is protruded from the panel. Because the plurality of fitting ports is formed in the housing main body on the outside of the casing, it is not required to prepare the connectors for each of the cable connectors, and therefore it becomes possible to decrease a number of installation work and to achieve space saving. Furthermore, the first water-proof seals prevent infiltration of moisture into the inside of the casing through the gaps between the circumferential walls of the fitting ports and the cable connectors. The second water-proof seal prevents filtration of moisture into the inside of the casing through the gap between the housing main body and the panel. Accordingly, it becomes possible to achieve space saving and to attach the electric connector to the panel which requires a high water-proof performance.

Hereinafter, with reference to the attached drawings, the present embodiment will be described. <FIG> is a perspective view showing a receptacle connector and a cable connector in the present embodiment. In the following description, a cable connector side of a panel is defined as a casing outside and an opposite side of the panel is defined as a casing inside. "FR", "RE", "U", "D", "L" and "R", marked in each figure respectively show a front direction, a rear direction, an upper direction, a lower direction, a left direction and a right direction. Hereinafter, an example in which the receptacle connector in the present embodiment is applied to an electric power assist bicycle will be described.

As shown in <FIG>, the receptacle connector (an electric connector) <NUM> is a composite connector attached to a panel <NUM> of a casing, and a plurality of cable connectors 60A to 60D (a counter connector) extending from an external unit, such as a lamp and a meter of the electric power assist bicycle, is connected to the receptacle connector <NUM>. The panel <NUM> of the casing has a rectangular attachment hole <NUM> long in the left-and-right direction. Through the attachment hole <NUM>, a rectangular cylindrical case part (a housing main body) <NUM> of the receptacle connector <NUM> is partially protruded from the outer face <NUM> of the panel <NUM>. The protruded portion of the case part <NUM> has fitting ports 24A to 24D through which the cable connectors 60A to 60B are fitted into the fitting ports 24A to 24D.

To the receptacle connector <NUM>, a plurality of cables <NUM> extending from an electric unit set in the casing inside S1 is connected. By fitting the cable connectors 60A to 60D into the fitting ports 24A to 24D of the receptacle connector <NUM>, the electric unit set in the casing inside S1 is electrically connected to the various external units set in the casing outside S2. In order to prevent misconnection between the connectors, the cable connectors 60A to 60D are formed to have different housing shapes. The fitting ports 24A to 24D of the receptacle connector <NUM> are formed to have shapes corresponding to the housing shapes of the cable connectors 60A to 60D.

As described above, by concentrating the cable connectors 60A to 60D extending from the external units in the same portion, the receptacle connector <NUM> makes it possible to achieve space saving and improve workability of the connection work, compared with a case where the receptacle connectors are provided for each external unit. Because the fitting ports 24A to 24D of the receptacle connector <NUM> have different opening shapes for each type of the cable connectors 60A to 60D, it becomes possible to prevent misconnection of the connectors. In the present embodiment, the receptacle connector <NUM> is connected to the electric unit via the cables <NUM>, but the receptacle connector <NUM> may be connected to a circuit board via a L-shaped terminal or the like.

Additionally, because various electric components are stored in the casing inside S1, a high water-proof performance is required for the attachment portion of the receptacle connector <NUM> to the panel <NUM> of the casing. Then, the receptacle connector <NUM> of the present embodiment includes first water-proof seals 40A to 40D which prevent infiltration of moisture into the casing inside S along the inner faces of the fitting ports 24A to 24D and a second water-proof seal <NUM> which prevents infiltration of moisture into the casing inside S1 along the outer face of the case part <NUM> (refer to <FIG>). Furthermore, the cable connectors 60A to 60D include third water-proof seals which prevent infiltration of moisture into the casing inside S1 along the outer faces of the cables <NUM> (<FIG> shows only the third water-proof seal 70B).

Hereinafter, configurations of the cable connector and the receptacle connector will be described in detail. <FIG> is a disassembled perspective view showing the cable connector in the present embodiment. <FIG> is a disassembled perspective view showing the receptacle connector in the present embodiment. <FIG> is a plan view showing the receptacle connector in the present embodiment, and <FIG> is a sectional view taken along the line A-A in <FIG>. <FIG> are perspective views showing a male type terminal in the present embodiment. <FIG> is an enlarged view partially showing a terminal storage space and its periphery in the present embodiment. <FIG> is a view showing an attachment state of the receptacle connector in the present embodiment. <FIG> is a front view showing the receptacle connector attached to the panel in the present embodiment, and <FIG> is a sectional view taken along the line B-B in <FIG>.

As shown in <FIG>, the cable connector 60B is a signal cable connector, and includes an approximately rectangular cylindrical housing 61B extending in the front-and-rear direction. In the front end portion of the housing 61B, a plurality of terminal insertion ports (not shown) is formed, and in the rear end portion of the housing 61B, a rectangular opening <NUM> is formed. Inside the housing 61B, a female type terminal <NUM> connected to each cable <NUM> is stored through the opening <NUM>. The female type terminals <NUM> are stored in the front end portion of the inside of the housing 61B. The front end face of each female type terminal <NUM> is exposed to an outside through the terminal insertion port of the housing 61B.

To the opening <NUM> of the housing 61B, the third water-proof seal 70B which seals between the housing 61B and the cables <NUM> is installed. The third water-proof seal 70B is made of elastic material, such as silicone rubber, formed into an approximately parallelepiped shape, and formed with a plurality of installation holes <NUM> along the front-and-rear direction into which the cables <NUM> are insertable tightly. The outer circumferential face of the third water-proof seal 70B comes into contact with the inner circumferential face of the housing 61B. Around the outer circumferential face of the third water-proof seal 70B, a plurality of annular projections <NUM> each having a mountain-like sectional shape is formed. By installing the third water-proof seal 70B to the opening <NUM> of the housing 61B, the plurality of annular projections <NUM> is slightly crushed to bring the third water-proof seal 70B into pressure-contact with the housing 61B.

On the upper face of the housing 61B, a lock mechanism <NUM> is provided, and the lock mechanism <NUM> keeps the fitting state of the housing 61B of the cable connector 60B into the fitting port 24B of the receptacle connector <NUM> (refer to <FIG>). The lock mechanism <NUM> has an arm part <NUM> extending rearward from the front side end portion of the housing 61B as a fixed end portion, a lock part <NUM> formed in a middle of the arm part <NUM> in its extending direction, and an operation part <NUM> provided in the free end portion of the arm part <NUM>. When the housing 61B is fitted into the fitting port 24B, the lock part <NUM> is engaged with a lock hole <NUM> (refer to <FIG>) described later, and the fitting state is kept. When the operation part <NUM> is pushed under the fitting state, the arm part <NUM> is pushed downward to disengage the lock part <NUM> from the lock hole <NUM> and then to release the fitting state.

On the upper face of the housing 61B, a pair of left and right protection parts <NUM> to protect the lock mechanism <NUM> is provided. The pair of left and right protection parts <NUM> prevents the arm part <NUM> from being deformed when an operator's hand or an article touches the operation part <NUM>, and also prevents the lock mechanism <NUM> from being inoperable by inserting of the cable <NUM> and the like between the lock mechanism <NUM> and the housing 61B. Here, although the four-wire cable connector 60B has been described as an example, a three-wire, a six-wire and a two-wire cable connectors 60A, 60B and 60C have the same basic configuration as the above example. Then, the descriptions of the three-wire, six-wire and two-wire cable connectors 60A, 60B and 60C are omitted.

As shown in <FIG>, <FIG>, the receptacle connector <NUM> includes a resin housing <NUM> attached to the panel <NUM> (refer to <FIG>) of the casing. The housing <NUM> has the case part <NUM> inserted into the attachment hole <NUM> of the panel <NUM> and a flange part <NUM> extending outwardly in the radial direction from the front end side outer circumferential face of the case part <NUM>. The case part <NUM> is formed into an approximately rectangular cylindrical shape extending in the front-and-rear direction and having a wide width in the left-and-right direction. In the upper wall of the case part <NUM>, a plurality of the lock holes <NUM> communicating with the fitting ports 24A to 24D is formed. With the lock holes <NUM>, the lock parts <NUM> (refer to <FIG>) of the cable connectors 60A to 60D are engaged.

In the rear end portion of the case part <NUM>, the fitting ports 24A to 24D having different opening shapes are formed side by side in the left-and-right direction. The fitting ports 24A to 24D extend from the rear end of the case part <NUM> to the center portion of the case part <NUM> in the front-and-rear direction. The fitting ports 24A to 24D are formed to have different opening shapes corresponding to the number of poles (the number of connection line of the cable <NUM>). For example, the fitting ports 24A to 24D are formed to have the opening shapes corresponding to the number of poles "three-wire", "four-wire", "six-wire" and "two-wire" respectively. The cable connectors 60A to 60D (refer to <FIG>) are formed to have housing shapes corresponding to the opening shapes of the fitting ports 24A to 24D respectively.

On the back faces of the fitting ports 24A to 24D, the first water-proof seals 40A to 40D are installed. The first water-proof seals 40A to 40D seal between the circumferential walls <NUM> of the fitting ports 24A to 24D and the cable connectors 60A to 60D (refer to <FIG>). The first water-proof seals 40A to 40D are made of elastic material, such as silicon rubber, and formed into annular shapes corresponding to the opening shapes of the fitting ports 24A to 24D, respectively. The first water-proof seals 40A to 40D each has a plurality of engagement pieces <NUM>. By pushing the first water-proof seals 40A to 40D on the inner bottom face of the case part <NUM>, the engagement pieces <NUM> are inserted into the engagement holes <NUM> formed in the circumferential wall <NUM> of the case part <NUM>, and the first water-proof seals 40A to 40D installed to the insides of the fitting ports 24A to 24D are prevented from being removed.

Around the outer circumferential face of the case part <NUM>, the second water-proof seal <NUM> is installed. The second water-proof seal <NUM> seals between the housing <NUM> and the panel <NUM>. The second water-proof seal <NUM> is formed into an annular shape. The second water-proof seal <NUM> is pushed in the front end portion of the case part <NUM> such that the front end portion of the second water-proof seal <NUM> is fitted into an annular groove <NUM> of the flange part <NUM>. Thereby, the second water-proof seal <NUM> is positioned to the casing inside S1 (refer to <FIG>) in a state where the receptacle connector <NUM> is attached to the panel <NUM>. In the casing inside S1, a gear or the like is stored in addition to the electric unit, and the gear is applied with grease as lubricant. Thereby, the second water-proof seal <NUM> is made of elastic material having excellent oil resistant property.

Around the outer circumferential face of the second water-proof seal <NUM>, a plurality of annular projections <NUM> having a mountain-like sectional shape is formed. Around the inner circumferential face of the second water-proof seal <NUM>, a plurality of annular projections <NUM> having a mountain-like sectional shape is formed. The annular projection <NUM> on the outer circumferential side has a protruding height higher than the annular projection <NUM> on the inner circumferential side, and the annular projection <NUM> on the outer circumferential side has a larger crushed amount. By installing the second water-proof seal <NUM> around the outer circumferential face of the case part <NUM>, the annular projection <NUM> on the inner circumferential side is crushed to bring the second water-proof seal <NUM> into pressure-contact with the case part <NUM>. Furthermore, by inserting the second water-proof seal <NUM> into the storage recess <NUM> (refer to <FIG>) of the panel <NUM>, the annular projection <NUM> on the outer circumferential side is crushed to bring the second water-proof seal <NUM> into pressure-contact with the storage recess <NUM> of the panel <NUM>.

In both the left and right end portions of the flange part <NUM>, a pair of fixed parts <NUM> is formed so as to fix the receptacle connector <NUM> to the panel <NUM>. The fixed part <NUM> has an insertion hole <NUM> for screwing. The outer circumferential face of the flange part <NUM> is formed asymmetrically in the upper-and-lower direction so as to prevent the receptacle connector <NUM> from being installed upside down. In the flange part <NUM>, the annular groove <NUM> is formed so as to surround the case part <NUM>. The annular groove <NUM> has the substantially same groove width as the thickness of the front end portion of the second water-proof seal <NUM>. By inserting the front end portion of the second water-proof seal <NUM> into the annular groove <NUM>, a seal performance between the flange part <NUM> and the second water-proof seal <NUM> is improved.

In the front end portion of the case part <NUM>, a plurality of terminal storage spaces <NUM> in which the male type terminals <NUM> connected to the cables <NUM> are stored is formed. The terminal storage space <NUM> is formed for each of the fitting ports 24A to 24D by the number of the connection wire of the corresponding cable <NUM>. The terminal storage spaces <NUM> extend from the front end of the case part <NUM> to the fitting ports 24A to 24D. The terminal storage spaces <NUM> are communicated with the fitting ports 24A to 24D. When the male type terminals <NUM> are stored in the corresponding terminal storage spaces <NUM> from the front end side of the case part <NUM>, the pin-like contacts <NUM> of the male type terminals <NUM> are protruded from the back faces of the fitting ports 24A to 24D.

As shown in <FIG>, the male type terminal <NUM> is made of electric conductive material, such as copper alloy, and formed by a cylindrical outer layer caulking part <NUM>, a cylindrical core wire caulking part <NUM>, a box-shaped middle part <NUM> and the pin-like contact <NUM> which are connected in the order from the base end side to the tip end side. The outer layer of the cable <NUM> is caulked by the outer layer caulking part <NUM>, the core wire protruding from the outer layer of the cable <NUM> is caulked by the core wire caulking part <NUM>, and then the male type terminal <NUM> is connected to the cable <NUM> (refer to <FIG>). The middle part <NUM> is a portion stored in the terminal storage space <NUM> (refer to <FIG>) of the case part <NUM>, and on one side face of the middle part <NUM>, a lance hole <NUM> engaged with a lance <NUM> described later is formed.

As shown in <FIG>, on the inner wall of the terminal storage space <NUM> of the case part <NUM>, the lance <NUM> with which the male type terminal <NUM> is engaged is provided. The lance <NUM> is inclined so as to be separated from the inner wall of the terminal storage space <NUM> in the insertion direction I1 of the male type terminal <NUM>. When the male type terminal <NUM> is inserted into the terminal storage space <NUM>, the lance <NUM> is pushed in, and then the male type terminal <NUM> is inserted to a predetermined position. When the male type terminal <NUM> is positioned to the predetermined position, the lance <NUM> is elastically returned and then the tip end portion of the lance <NUM> is inserted in the lance hole <NUM> (refer to <FIG>) of the male type terminal <NUM>. Then, the male type terminal <NUM> is fixed to the terminal storage space <NUM>, and the cable <NUM> is prevented from being removed from the receptacle connector <NUM>.

Because the male type terminal <NUM> is installed to the receptacle connector <NUM> via the lance <NUM>, the prevention of the removal of the male type terminal <NUM> by the lance <NUM> can be released by using a specific tool. Thereby, even if the male type terminal <NUM> is incorrectly inserted into the terminal storage space <NUM> of the receptacle connector <NUM>, the prevention of the removal of the male type terminal <NUM> by the lance <NUM> can be released by using the specific tool, and it becomes possible to remove the male type terminal <NUM> from the receptacle connector <NUM> easily. In the above manner, because the male type terminal <NUM> connected to the cable <NUM> is directly installed to the receptacle connector <NUM>, it becomes possible to make the connector configuration of the receptacle connector <NUM> simple and decrease the cost.

As shown in <FIG>, <FIG>, the receptacle connector <NUM> is fixed to the panel <NUM> with a pair of bolts <NUM>. The panel <NUM> has an annular protruded part <NUM>. The annular protruded part <NUM> is protruded from the inner face <NUM> of the panel <NUM> to the casing inside S1 so as to surround the attachment hole <NUM>. Inside the annular protruded part <NUM>, the storage recess <NUM> in which the receptacle connector <NUM> is stored is formed. The storage recess <NUM> is formed to be front and rear two steps by a front step recess <NUM> in which the flange part <NUM> of the housing <NUM> is storable and a rear step recess <NUM> in which the second water-proof seal <NUM> installed to the case part <NUM> of the housing <NUM> is storable.

In the front step recess <NUM> of the storage recess <NUM>, the positioned flange part <NUM> of the housing <NUM> is stored. In detail, the inner circumferential face of the front step recess <NUM> is formed asymmetrically in the upper-and-lower direction corresponding to the upper-and-lower asymmetric outer circumferential face of the flange part <NUM>. Thereby, the flange part <NUM> is prevented from being stored in the front step recess <NUM> upside down, and it becomes possible to attach the receptacle connector <NUM> to the panel <NUM> in the correct orientation. On the bottom face of the front step recess <NUM>, a pair of screw holes <NUM> is formed at a position corresponding to the pair of insertion holes <NUM> of the flange part <NUM> in a state where the flange part <NUM> is stored to the front step recess <NUM>.

In the rear step recess <NUM> of the storage recess <NUM>, the second water-proof seal <NUM> installed to the case part <NUM> is tightly stored. On the bottom face of the rear step recess <NUM>, the attachment hole <NUM> into which the case part <NUM> exposed from the second water-proof seal <NUM> is inserted is formed. When the receptacle connector <NUM> is attached to the panel <NUM>, the case part <NUM> is inserted into the attachment hole <NUM>, the second water-proof seal <NUM> is stored in the rear step recess <NUM> and the flange part <NUM> is stored in the front step recess <NUM>. Then, the pair of bolts <NUM> is screwed to the pair of screw holes <NUM> through the pair of insertion holes <NUM> of the flange part <NUM>, and then the receptacle connector <NUM> is attached to the panel <NUM>.

Next, with reference to <FIG> and <FIG>, an installation operation of the cable connector to the receptacle connector and a water-proof configuration of the receptacle connector will be described. <FIG> are transition diagrams showing the installation operation of the cable connector of the present embodiment. <FIG> is a sectional view showing the water-proof configuration of the receptacle connector of the present embodiment. Here, the four-wire cable connector will be described as an example, and the three-wire, six-wire and two-wire cable connectors have the same configuration as the above example.

As shown in <FIG>, the receptacle connector <NUM> is attached to the panel <NUM> with the case part <NUM> protruding from the outer face <NUM> of the panel <NUM>. On the back face of the fitting port 24B of the case part <NUM>, the first water-proof seal 40B is installed. Around the outer circumferential face of the case part <NUM>, the second water-proof seal <NUM> is installed. The annular projection <NUM> on the outer circumferential side of the second water-proof seal <NUM> is crushed by the inner circumferential face of the storage recess <NUM>, and the annular projection <NUM> (refer to <FIG>) on the inner circumferential side of the second water-proof seal <NUM> is crushed by the outer circumferential face of the case part <NUM>. The second water-proof seal <NUM> seals between the storage recess <NUM> of the panel <NUM> and the case part <NUM>.

In the cable connector 60B, the third water-proof seal 70B is installed to the opening <NUM> in the rear end portion of the housing 61B. Into the installation hole <NUM> (refer to <FIG>) of the third water-proof seal 70B, the cable <NUM> is tightly inserted. The annular projection <NUM> on the outer circumferential side of the third water-proof seal 70B is crushed by the inner circumferential face of the housing 61B. The third water-proof seal 70B seals the rear end portion of the housing 61B of the cable connector 60B. Then, the cable connector 60B is placed to face the opening of the fitting port 24B of the receptacle connector <NUM>, and then the cable connector 60B is pushed in the fitting port 24B in the insertion direction I2.

As shown in <FIG>, when the housing 61B is inserted into the fitting port 24B, the arm part <NUM> of the lock mechanism <NUM> on the upper face of the housing 61B is pushed downward, and the housing 61B is displaced in the insertion direction I2. When the housing 61B comes into contact with the back face of the fitting port 24B, the arm part <NUM> is elastically returned, the lock part <NUM> is inserted into the lock hole <NUM> of the case part <NUM>, and the fitting state of the housing 61B into the fitting port 24B is kept. At this time, the front end portion of the housing 61B enters the inside of the first water-proof seal 40B, and the first water-proof seal 40B seals between the circumferential wall <NUM> of the fitting port 24B and the housing 61B.

As shown in <FIG>, a slight gap is formed between the panel <NUM> and the receptacle connector <NUM>, and a slight gap is formed between the receptacle connector <NUM> and the cable connector 60B. Then, in the portion where the receptacle connector <NUM> is attached, a moisture infiltration path from the casing outside S2 to the casing inside S1 exists. For example, the moisture infiltration path contains a first infiltration path L1 along which moisture infiltrated from the lock hole <NUM> or the others of the case part <NUM> flows to the casing inside S1, a second infiltration path L2 along which moisture infiltrated through the gap between the case part <NUM> and the panel <NUM> flows to the casing inside S1, and a third infiltration path L3 along which moisture flows to the casing inside S1 through the cable <NUM> of the cable connector 60B.

However, on a middle of the first infiltration path L1, the first water-proof seal 40B is disposed. The first water-proof seal 40B seals between the circumferential wall <NUM> of the fitting port 24B and the housing 61B. On a middle of the second infiltration path L2, the second water-proof seal <NUM> is disposed. The second water-proof seal <NUM> seals between the case part <NUM> and the storage recess <NUM> of the panel <NUM>. On a middle of the third infiltration path L3, the third water-proof seal 70B is disposed. The third water-proof seal 70B seals between the housing 61B and the cable <NUM>. In the above configuration, all of the first to third infiltration paths L1 to L3 from the casing outside S2 to the casing inside S1 are blocked to improve a water-proof performance of the casing inside S1.

Furthermore, the case part <NUM> of the receptacle connector <NUM> is partially protruded from the outer face <NUM> of the panel <NUM>, and separates the operation part <NUM> of the cable connector 60B from the outer face <NUM> of the panel <NUM>. By separating the operation part <NUM> from the outer face <NUM> of the panel <NUM>, it becomes possible to operate the operation part <NUM> easily by the operator's finger and to improve the operation performance of the operation part <NUM>. Additionally, on the upper face of the case part <NUM>, the plurality of lock holes <NUM> is formed for each of the fitting ports 24A to 24D (refer to <FIG>). Thereby, the operation parts <NUM> can be operated from the same upper side for the cable connectors 60A to 60D fitted into the fitting ports 24A to 24D, and the operation performance of the operation part <NUM> by the operator can be further improved.

With reference to <FIG>, another using example of the receptacle connector in the present embodiment will be described. <FIG> is a perspective view showing the another using example of the receptacle connector in the present embodiment.

The above described embodiment describes an example where the cable connectors 60A to 60D having different numbers of pole are installed to all of the fitting ports 24A to 24D of the receptacle connector <NUM>, but the using example of the receptacle connector is not limited to the above example. The receptacle connector <NUM> of the present embodiment can be variously applied depending on requirement of the user. For example, as shown by the other using example in <FIG>, only three of the fitting ports 24A, 24B and 24D among the four fitting ports 24A to 24D (refer to <FIG>) may be used, and the three-wire cable connector 60A and the four-wire cable connector 60B may be used as the two-wire cable connector.

In this case, into the unused fitting port 24C of the receptacle connector <NUM>, a cable connector shaped cap <NUM> is fitted. The cap <NUM> has the same outer shape as the housing 61C (refer to <FIG>) of the cable connector 60C only except that an inner space is not formed. In place of the housing 61C of the cable connector 60C, the cap <NUM> is fitted into the unused fitting port 24C, and therefore, the first water-proof seal 40C (refer to <FIG>) seals between the fitting port 24C and the cap <NUM>. Thereby, it becomes possible to prevent infiltration of moisture through the unused fitting port 24C into the casing inside S1.

In the three-wire cable connector 60A, the cables <NUM> are inserted into the two installation holes <NUM> among the three installation holes <NUM> of the third water-proof seal 70A while a water-proof rod <NUM> is inserted into the remaining one installation hole <NUM> tightly. In the four-wire cable connector 60B, the cables <NUM> are inserted into the two installation holes <NUM> among the four installation holes <NUM> while the water-proof rods <NUM> are inserted into the remaining two installation holes <NUM> tightly. By the third water-proof seals 70A and 70B into which the water-proof rods <NUM> are inserted, it becomes possible to use the three-wire cable connector 60A and the four-wire cable connector 60B as a two-wire cable connector.

As described above, according to the present embodiment, because the plurality of fitting ports 24A to 24D is formed on the casing outside S2 of the case part <NUM>, it is not required to prepare the connectors for each of the cable connectors 60A to 60D, and therefore it becomes possible to decrease a number of installation work and to achieve space saving. Additionally, the first water-proof seals 40A to 40D prevent infiltration of moisture into the casing inside S1 through the gaps between the circumferential walls <NUM> of the fitting ports 24A to 24D and the cable connectors 60A to 60D. The second water-proof seal <NUM> prevents filtration of moisture into the casing inside S1 through the gap between the case part <NUM> and the panel <NUM>. Furthermore, the third water-proof seals 70A to 70D prevent infiltration of the moisture into the casing inside S1 through the cables <NUM> of the cable connectors 60A to 60D. Accordingly, it becomes possible to achieve space saving and to attach the receptacle connector <NUM> to the panel <NUM> which requires a high water-proof performance.

The present embodiment describes the receptacle connector <NUM> having the case part <NUM> in which the fitting ports 24A to 24D are formed side by side in a row and attached to the panel <NUM> from the casing inside S1, but is not limited the above configuration. As shown by a modified example in <FIG>, the receptacle connector <NUM> may have the case part <NUM> in which the fitting ports 98A to 98D are formed side by side in upper and lower two rows, and may be attached to the panel <NUM> from the casing outside S2. Into the fitting ports 98A to 98D of the case part <NUM>, the first water-proof seals 101A to 101D are installed. Around the outer circumferential face of the case part <NUM>, the second water-proof seal <NUM> is installed.

The flange part <NUM> is provided in the rear end portion of the case part <NUM>, and the annular protruded part <NUM> is formed on the outer face <NUM> of the panel <NUM> so as to surround the attachment hole <NUM>. On the face of the annular protruded part <NUM>, the pair of screw holes <NUM> is formed. A pair of bolts <NUM> is screwed to the pair of screw holes <NUM> through the pair of insertion holes <NUM> of the flange part <NUM>, and then the receptacle connector <NUM> is attached to the panel <NUM>. When the receptacle connector <NUM> is attached to the panel <NUM>, the cable connectors 103A to 103D are installed to the fitting ports 98A to 98D of the receptacle connector <NUM>.

The present embodiment describes the signal cable connector as a plurality of cable connector, but the plurality of cable connector may include a signal cable connector and a power cable connector. For example, as shown by a modified example in <FIG>, the case part <NUM> of the receptacle connector <NUM> may have a plurality of approximately rectangular fitting ports 107A to 107D for a plurality of the signal cable connectors and an approximately circular fitting port <NUM> for the power cable connector. Thereby, it becomes possible to integrate the receptacle connector for the signal cable connector and the receptacle connector for the power cable connector together and to decrease the cost by decreasing the number of members and the number of work process.

The present embodiment describes an example where the receptacle connector is used for the electric power assist bicycle, but the receptacle connector may be used for a vehicle such as an electric power scooter and an
electric power wheelchair, an apparatus requiring a water-proof performance and the like.

In the present embodiment, the fitting ports of the receptacle connector are formed to have different opening shapes, but the fitting ports of the receptacle connector may be formed to have the same opening shape.

In the present embodiment, the second water-proof seal is made of elastic material having oil resistant property, but in a case where the receptacle connector is attached to an apparatus which does not use lubricant, such as grease, the second water-proof seal may be made of elastic material, such as silicon rubber.

In the present embodiment, the outer circumferential face of the flange part is formed asymmetrically in the upper-and-lower direction, but the outer circumferential face of the flange part may be formed rotationally asymmetrically. For example, the outer circumferential face of the flange part may be formed asymmetrically in the left-and-right direction.

In the present embodiment, the case part is protruded from the outer face of the panel, but the case part may not be protruded from the outer face of the panel. The case part may be formed to expose the plurality of fitting ports from the outer face of the panel so as to be connected to the cable connectors.

Claim 1:
An electric connector (<NUM>) which is configured to be connected to a plurality of counter cable connectors (60A to 60D), and provided with a housing configured to be attached to an attachment hole (<NUM>) of a panel (<NUM>) of a casing, a counter cable connectors connecting side of the panel is defined as an outside of the casing (S2) and an opposite side of the panel is defined as an inside of the casing (S1), wherein
the housing includes a housing main body (<NUM>) configured to be inserted into the attachment hole of the panel and a flange part (<NUM>) extending outward from an outer circumferential face of the housing main body,
the housing main body has a plurality of fitting ports (24A to 24D) into which the plurality of counter cable connectors is configured to be fitted, on the outside of the casing, and
the flange part has a fixed part (<NUM>) fixed to the panel and an annular groove formed so as to surround the housing main body, wherein
a first water-proof seal (40A to 40D) which is configured to prevent infiltration of moisture into the inside of the casing along inner faces of the fitting ports is installed to each of the fitting ports,
the first water-proof seal is configured to seal between a circumferential wall (<NUM>) of each of the fitting ports and each of the counter cable connectors,
characterized by
a second water-proof seal (<NUM>) which is configured to prevent prevents infiltration of moisture into the inside of the casing along the outer face of the housing main body is installed around an outer circumferential face of the housing main body, a front end portion of
the second water-proof seal being inserted into the annular groove, and
the second water-proof seal is configured to seal between the housing main body (<NUM>) and the panel (<NUM>).