Patent Publication Number: US-6705881-B2

Title: Lever-type connector

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a lever-type connector with a connection detecting function. 
     2. Description of the Related Art 
     A lever-type connector comprises first and second housings that are connectable with one another. A lever is mounted pivotally on the first housing and a cam pin projects from the second housing. The cam pin is inserted into a cam groove formed in the lever during the connection of the housings. The lever then is pivoted to a specified connection position, and the cam action of the cam groove and the cam pin pull the housings into connection. 
     An operator normally judges the proper connection of the two housings in the above-described lever-type connector by a locking sound and a locking feeling given when the lever is locked at the connection position. However, the locking sound and the locking feeling may not be given if the locking mechanism does not have a precise shape. Hence there is a possibility that the operator may make a wrong judgment. 
     A lever-type connector designed to detect a connected state of housings electrically is shown in U.S. Pat. No. 5,135,410. This connector has a lever with electrically conductive contacts, and the mating housing has two detection terminals connected with a detection circuit. The detection terminals are brought into contact with contacts of the lever when the lever reaches a connection position during the connection of the two housings. Thus, the detection terminals are shorted to detect the properly connected state of the housings. 
     However, the contacts of the lever and the detection terminals are on the outer surfaces of the housings and they may be deformed by contact with external matter, for example, during transportation before the housings are connected. Thus, the connection detection function of this connector has lacked reliability. Further, it is very difficult to achieve waterproofing because the detection terminals are on the outer surface of the housings. 
     In view of the above, an object of the invention is to provide a lever-type connector that can detect a connected state of housings electrically, and that has an improved connection detecting reliability. 
     SUMMARY OF THE INVENTION 
     The invention is directed to a lever-type connector with at least first and second housings that are connectable with each other. A lever is displaceably mounted on the first housing. The lever and the second housing are provided with a cam mechanism that comprises a cam groove and a cam pin engageable with the cam groove. The cam pin is insertable into the cam groove when the lever is at a standby position. The lever then can be operated so that the cam action of the cam mechanism pulls the housings toward each other and into a connected condition. 
     An electric or electronic non-contact detector is provided for detecting when the lever is in the connection position, and hence for detecting whether the housings are connected properly. The electric non-contact detector is turned on or detects the lever in the connection position without contacting the lever. Thus, detection terminals and contacts need not be provided on the outer surface of the housings, and, unlike the prior art, deformation, oxidation and the like can be reduced. As a result, the reliability of the connection detecting function can be improved. 
     The electric non-contact detector preferably comprises an electromagnetic device integrally in the lever and a lead switch in one of the housings. The electromagnetic device turns on the lead switch as the lever is displaced to the connection position. The lead-switch preferably comprises contacts hermetically sealed in a housing and is connected with a detecting circuit or the like. Thus, a properly connected state of the housings can be detected electrically. The lead switch is turned on without contacting the lever and there are no detection terminals and contacts on the outer surfaces of the housings. Accordingly, no parts of the detector are subject to deformation or oxidation and connection detection is more reliable than in the prior art. 
     A watertight area may be formed between the connected housings. The lead switch operates without contacting the lever, and hence can be sealed in the watertight area. 
     The electric non-contact detector preferably is connectable to a detection circuit by terminal fittings in at least one of the housings. 
     At least part of the electric non-contact detector preferably is provided in at least one of the housings by integral molding. 
     The lever preferably abuts at least one stopper at connection position. Additionally, locking means may lock the lever at the standby position and/or the connection position. 
     These and other objects, features and advantages of the present invention will become more apparent upon reading of the following detailed description of preferred embodiments and accompanying drawings. It should be understood that even though embodiments are described separately, single features thereof may be combined to additional embodiments. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side view showing a state of a female housing and a male housing according to one embodiment of the invention before connection. 
     FIG. 2 is a front view in section showing the state of the female and male housings before connection. 
     FIG. 3 is a plan view of the female connector housing. 
     FIG. 4 is a plan view of the male connector housing. 
     FIG. 5 is a side view showing a state of the female and male housings after completion of connection. 
     FIG. 6 is a front view in section showing the state of the female and male housings after completion of connection. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A lever-type connector according to the invention includes a female housing  10  and a male housing  40  connectable with and separable from each other. A wire cover  20  is mounted on the female housing  10  for substantially covering at least portions of wires W, and a lever  30  is mounted on the wire cover  20  for assisting the connection of the female and male housings  10 ,  40 . In the following description, reference is made to FIG. 1 concerning the vertical direction, and the left side in FIG. 1 is referred to as the front side. 
     The female housing  10  is made e.g. of a synthetic resin and defines a substantially rectangular parallelepipedic shape. Vertically extending cavities  11  are formed in two transversely extending rows, and female terminal fittings  12  are inserted into the cavities  11  preferably from behind when seen in a connecting direction with the male connector housing  40 . One end of each female terminal fitting  12  is crimped into connection with an end of the wire W and a rubber plug  13 . Each wire W is drawn out above the female housing  10  from the corresponding cavity  11 . A clearance at an upper part of each cavity  11  between the inner surface of the cavity  11  and the outer surface of the wire W is sealed hermetically by the rubber plug  13 . An annular sealing member  14  is mounted on the outer surface of a base end portion of the female housing. 
     The wire cover  20  is made e.g. of a synthetic resin and is substantially in the form of a box that opens down and back, as shown in FIGS. 1 to  3 . The bottom opening of the wire cover  20  is mounted to an upper part of the female housing  10 . The wires W from the cavities  11  are bent at substantially right angles inside the wire cover  20  and are drawn out through the rear opening of the wire cover  20 . Left and right lateral supporting shafts  23  project from the opposite side surfaces of the wire cover  20 , and the lever  30  is mounted on the supporting shafts  23  to substantially surround the wire cover  20 . 
     The lever  30  is made e.g. of a synthetic resin, and is substantially U-shaped. More particularly, the lever  30  includes a transversely extending operable portion  31  and plate-shaped arms  32  that extend from opposite ends of the operable portion  31 . A bar-shaped permanent magnet  33  is embedded in the operable portion  31  by integral molding and has N- and S-poles at opposite transverse ends or exit the lever  30  at the plate-shaped arms  32 . 
     Base ends of the arms  32  are widened for mounting on the supporting shafts  23 , so that the lever  30  is pivotal about the shafts  23  between a standby position and a connection position. At the standby position shown in FIGS. 1 and 2, the operable portion  31  contacts the upper surface of the wire cover  20  to restrict any further clockwise rotation of the lever  30 , and the lever  30  is held by engagement of substantially round first projections  25 A on opposite sides of the wire cover  20  with first locking holes  34 A in the arms  32 . Cam grooves  35  are formed at base ends of the arms  32 , and entrances  35 A of the cam grooves  35  face down toward the male housing  40  at the standby position. 
     Leading ends of the arms  32  contact stoppers  26  that project from the opposite side surfaces of the wire cover  20  at the connection position shown in FIGS. 5 and 6. The stoppers  26  restrict any further counterclockwise rotation of the lever  30  in FIG.  5 . Thus, the lever  30  is held by the engagement of substantially rectangular second projections  25 B that project immediately above the stoppers  26  and second locking holes  34 B of the arms  32 . 
     The male housing  40  is mountable on an unillustrated circuit board, and has a substantially rectangular tubular receptacle  41  that opens up toward the female housing  10 . A mounting wall  42  substantially closes the bottom end of the receptacle  41 , as shown in FIGS. 1,  2  and  4 . The bottom part of the female housing  10  is fittable into the receptacle  41  so that the sealing member  14  is held in close contact with the outer surface of the female housing  10  and the inner surface of the receptacle  41 . Thus, watertight spaces are defined inside the receptacle  41  and inside the cavities  11  before the rubber plugs  13  and are sealed from the outside. Cam pins  44  project from the left and right lateral outer surfaces of the receptacle  41 . Long narrow substantially L-shaped male terminal fittings  45  penetrate the mounting wall  42  in two rows, such that one end of each terminal fitting  45  projects into the receptacle  41  for connection with the corresponding female terminal fitting  12  when the female and male housings  10 ,  40  are connected. The other ends of the male terminal fittings  45  penetrate through an alignment plate  46  on the male housing  40 . 
     A narrow lead switch chamber  48  extends transversely at the bottom surface of the receptacle  41  and is formed at one end (front end) with respect to longitudinal direction. The lead switch  50  for detecting the connection is accommodated in the switch chamber  48 , as shown in FIG.  4 . The lead switch  50  is such that contacts are sealed hermetically with an insert gas (e.g. He, Ar or the like) in a narrow transversely extending glass tube  51 , and electrodes  52  project from the opposite ends of the glass tube  51 . Each electrode  52  is soldered to the closest one  45 A of the male terminal fittings  45  of the corresponding row. During connection of the female and male housings  10 ,  40 , the magnet  33  approaches the lead switch  50  as the lever  30  is pivoted from the standby position to the connection position. The lead switch  50  is turned on by a magnetic force of the magnet  33  when the lever  30  is at the connection position and when the magnet  33  is closest to the lead switch  50 . Conversely, the lead switch  50  is turned off when the lever  30  leaves the connection position and moves toward the standby position because the magnetic force of the magnet  33  is not sufficient to keep the lead switch  50  on. 
     The female and male housings  10 ,  40  are connected by first pivoting the lever  30  to the standby position (see FIGS.  1  and  2 ). This brings the entrances  35 A of the cam grooves  35  to positions where they can oppose the cam pins  44 . In this state, the housings  10 ,  40  are brought closer to and lightly connected with each other so that the cam pins  44  enter the entrances  35 A of the cam grooves  35 . The lever  30  then is pivoted toward the connection position, and the housings  10 ,  40  are pulled together by the cam action of the cam grooves  35  and the cam pins  44 . The female and male housings  10 ,  40  are connected properly with each other when the lever  30  reaches the connection position, and the lead switch  50  is turned on by the magnetic force of the magnet  33 . The properly connected state of the housings  10 ,  40  can be detected by the external detecting circuit connected with the lead switch  50 . 
     The lead switch  50  is turned on without contacting the lever  30 . Thus, unlike the prior art, the detection terminals and the contacts need not be provided on the outer surfaces of the housings. Further, the contacts are in the glass tube  51  and are not subject to deformation, oxidation and the like. As a result, the reliability of the connection detecting function can be improved. 
     Further, the lead switch  50  operates without contacting the lever  30 , and can be sealed securely in the watertight area inside the receptacle  41 . 
     The present invention is not limited to the above described and illustrated embodiment. For example, following embodiments are also embraced by the technical scope of the present invention as defined in the claims. Beside the following embodiments, various changes can be made without departing from the scope and spirit of the present invention as defined in the claims. 
     The lead switch  50  is in the housing that mates with the housing on which the lever  30  is mounted in the foregoing embodiment. However, the lead switch may be in the housing on which the lever is mounted. 
     The lever-type connector is a watertight connector with watertight areas in the foregoing embodiment. However, the invention is also applicable to connectors other than watertight connectors. 
     Even though the invention has been described with reference to a lead switch and a magnet, any other electrical/electronic proximity switch of the non-contact type, such as a transducer, may be used. 
     Even though the invention has been described with a reference to a lever pivotally provided on one of the connector housings, the lever may be movable along a linear or other non-linear path, such as a slider.