Abstract:
A flat and thin connector for electrically connecting a flexible printed circuit board and a hard board. The connector includes a mounting member fixed to the hard board, and a pusher member cooperating with said mounting member. The pusher member urges the printed circuit board against the hard board by aid of an elastic member. Further, the printed circuit board is provided with slits between the bump contacts to facilitate a uniform pushing force.

Description:
BACKGROUND OF THE INVENTION 
   The present invention relates to a connector for use in a mobile or cellular phone, notebook personal computer, digital camera and the like, more particularly to a connector for connecting a flexible printed circuit board and a hard board, which is intended to be more miniaturized and flattened and thinner, and more particularly to a mounting member used for connecting the flexible printed circuit board to the hard board, which contributes to the miniaturization of flattened and thinner connector and a method for mounting the mounting member on the hard board. 
   One kind of the connector used in a mobile phone, charge coupled device (CCD) camera and the like mainly comprises a housing and contacts, and when a flexible printed circuit board is inserted into the housing, it is brought into contact with contact portions of the contacts. This type of connector is so-called “non-zero-insertion force” (NZIF) type. A connector of the other kind mainly comprises a housing, contacts and a slider so that a flexible printed circuit board is embraced by the housing and the slider (so-called “zero-insertion force” (ZIF) type and “piano touch” type). There are various methods for holding the flexible printed circuit board by the housing and the slider. In many cases, however, after a flexible printed circuit board has been inserted into the housing, the slider is inserted into the housing to urge the flexible printed circuit board against contacts, or after a flexible printed circuit board has been inserted, a slider is pivotally moved to urge a flexible printed circuit board to contacts. 
   The housing is formed with a required number of insertion apertures for inserting the contacts therein and a fitting hole for inserting the flexible printed circuit board. The contacts mainly comprise a contact portion adapted to contact a flexible printed circuit board, a connection portion to be connected to a hard board, and a fixing portion to be fixed to the housing. These contacts are usually fixed to the housing as by press-fitting. 
   Japanese Utility Model Application Opened No. H6-60,983 discloses one example of connectors of the “zero-insertion force” type. As can be seen from the “Abstract” of the Japanese Utility Model, this invention relates to a connector with a slider for a printed circuit board for use in a narrow space in an electronic or communication appliance. The slider is formed at ends of both sides with U-shaped arms with their proximal ends fixed to the slider as guiding means when being inserted into a housing. The U-shaped arms are each provided on its opening side with a projection and formed with a notch such that the opening end is visible from the inserting side. The housing is provided at both the ends with projections having an oblique surface adapted to engage the projections of the slider. 
   When the slider together with connection terminals of a flexible printed circuit board is inserted into the housing, the projections of the slider ride over the projections having the oblique surface of the housing so that the opening ends of the U-shaped arms of the slider are temporarily spread outwardly and then returned to their normal positions when the insertion has been completed. 
   Japanese Patent Application Opened No. H13-257,020 discloses one example of the so-called “piano touch” type connector. With a view to obtaining an accurate positioning of contacts of the disclosed connector relative to a flexible printed circuit board or its pattern, projections are provided in a row on a line on a terminal block between the contacts. After a flexible printed circuit board or flexible flat cable has been inserted into the terminal block, a slider is moved to urge the circuit board or flat cable against the contacts. At the moment when the circuit board or flat cable is electrically connected to the contacts by the slider in this manner, the projections snap into recesses between patterns of the circuit board or flat cable, thereby ensuring positional coincidence between the contacts and patterns of the circuit board or flat cable. 
   With miniaturization of electric or electronic appliances, recently, connectors for use in such appliances have been more strongly required to be more miniaturized to more flattened and thinner connectors with narrower pitches of contacts. 
   With the connectors disclosed in the Japanese Patent and Utility Model Applications, first the connector is fixed to a hard board as by reflow soldering and a flexible printed circuit board is then inserted into the connector to connect the flexible and hard boards. Such a connector comprises at least a housing and contacts fixed to the housing as by press-fitting as essential components. With such a connector, a technical problem remains that more miniaturization has been impossible such as narrower contact pitches, more space-saving and more flattened or thinner (less than 1 mm thickness). The miniaturization is limited by the workability and strength of insulating plastic materials forming housing of connectors and further limited by the fact that the housing is required to have the minimum required thickness for press-fitting contacts therein. Moreover, there may be a requirement of miniaturization as regards in longitudinal or traverse direction of a connector owing to other components and jigs for disassembling or the like. 
   Under such circumstances, with miniaturization of peripheral electric or electronic appliances, the connectors of the kinds mentioned in the above paragraphs have been strongly required to be more miniaturized. For this purpose, the applicant has proposed a connector in Japanese Patent Application No. 29,198/2003. 
   With the connector disclosed in the above Japanese Patent Application No. 29,198/2003, in order to automatically mount a mounting member onto a hard board by a suction mounter, the mounting member is first temporarily secured to the hard board by adhesive tapes and then set in position on the hard board by the suction mounter, because the mounting member does not have a portion to be sucked by a suction mounter. Therefore, this process involves additional steps and management for installing, removing and discarding the tapes, resulting in high cost manufacture and potential environment deterioration. When the mounting member is sucked by the suction mounter, there would be a risk for the thin mounting member being deformed, if the suction is too strong. 
   SUMMARY OF THE INVENTION 
   It is an object of the invention, in view of the problems of the prior art, to provide a connector which fulfils the requirements with respect to more miniaturization, more flatness, more thinner and narrower pitches of contacts, and a mounting member which can be easily mounted on a hard board and a method for mounting the mounting member onto the hard board. 
   In order to accomplish the object for achieving more miniaturization, more flatness, more thinner and narrower pitches of a connector, in the connector for connecting a flexible printed circuit board and a hard board according to the invention, the flexible printed circuit board comprises contact portions, each contact portion comprising a bump contact thereon, and the flexible printed circuit board is formed with slits between the bump contacts, or between pairs of bump contacts, each pair consisting of two adjacent bump contacts, or between the bump contacts arbitrarily selected to provide a compliance to these bump contacts. The connector according to the invention, moreover, comprises a mounting member arranged on the hard board, bump contacts on contact portions of the flexible printed circuit board, an elastic member on the surface of the flexible printed circuit board on the opposite side of the bump contacts, and a pusher member for urging the flexible printed circuit board and the elastic member toward the hard board, thereby engaging the pusher member with the mounting member to cause the flexible printed circuit board to connect to the hard board. 
   The connector according to the invention comprises a mounting member arranged on the hard board, bump contacts on contact portions of the flexible printed circuit board, an elastic member on the surface of the flexible printed circuit board on the opposite side of the bump contacts, and a pusher member for urging the flexible printed circuit board and the elastic member toward the hard board, thereby engaging the pusher member with the mounting member to cause the flexible printed circuit board to connect to the hard board. With this construction, more miniaturization, more flatness and narrower pitches of the connector can be accomplished. 
   In the connector according to the invention, two tab portions of the mounting member to be connected to the hard board are made substantially in the same shape as that of land areas of the hard board within a range to be affected by surface tension of molten solder so that the mounting member is positioned in place on the hard board with the aid of self-alignment effect. In this manner, the mounting member can be arranged in place on the hard board with the aid of the self-alignment effect caused by the surface tension of molten solder. 
   According to the invention, the mounting member includes the two tab portions integrally connected. By connecting the two tab portions, the positioning of the mounting member relative to the hard board can be readily carried out because members to be positioned become only one member. 
   According to the invention, the hard board is provided with a plurality of circular lands and the mounting member is provided with exposed connecting portions having a shape the same as that of the lands at locations corresponding to the circular lands on the hard board. By providing the circular lands, the surface tension becomes likely to occur to enhance the self-alignment effect. 
   In the connector according to the invention, the flexible printed circuit board and the elastic member are fixed to each other so that when the pusher member is engaged with the mounting member, the pusher member is accurately held in a desired position relative to the mounting member. By fixing together these members, setting of these members in place can easily be performed. 
   According to the invention, a pushing portion of the pusher member consists of two members adhered together. The pusher member becomes stronger in this manner. 
   The two members of the pusher member are made of the same material and different in thickness or shape, or the two members are made of different materials and different in thickness or shape. Moreover, one of the two members of the pusher member on the side of the elastic member has a curved shape such that the urging force is uniformly distributed. 
   According to the invention, the pusher member is provided with anchor portions bent in the form of a U-shape at locations corresponding to engaging portions of the mounting member. This construction will contribute to the flatness and miniaturization in the width direction of the connector. 
   The mounting member according to the invention comprises a plurality of mounting portions each including a tab portion to be fixed to a hard board and an engaging portion to engage a mating member, and the plurality of mounting portions being integrally connected by a connecting member provided with at least one protrusion plate connected thereto. As a result, automatic mounting becomes possible, resulting in low cost manufacture. 
   The method for mounting a mounting member onto a hard board by soldering according to the invention comprises steps of sucking a protrusion plate of the mounting member, arranging the mounting member in place on the hard board, fixing the mounting member to the hard board by reflow soldering, and removing the protrusion plate from the mounting member. According to the method, the mounting member can be easily fixed to the hard board without increasing manufacturing cost and without causing environment deterioration. 
   Preferably, tab portions of the mounting member are made substantially in the same shape as that of land areas on the hard board, and the mounting member is arranged within a range to be affected by surface tension of molten solder to provide self-alignment effect in reflow soldering. In this manner, the mounting member can be arranged in place on the hard board with the aid of the self-alignment effect owing to the surface tension of the molten solder. 
   According to the invention, the protrusion plate is formed so as to provide at least one clearance between the hard board and the protrusion plate at any portion of it. Moreover, a connecting portion between the protrusion plate and the connecting member is formed with at least one notch. The protrusion plate is removed from the mounting member after the mounting member has been arranged and fixed in place on the hard board by reflow soldering. 
   According to the invention, the flexible printed circuit board is formed with slits between the bump contacts, or between pairs of bump contacts, each pair consisting of two adjacent bump contacts, or between the bump contacts arbitrarily selected so as to permit individual bump contacts to be independent of one another to provide compliance to the bump contacts sufficient to accommodate differences in height of these bump contacts, thereby obtaining stable connection between the flexible and hard boards. 
   According to the invention, two tab portions of the mounting member to be connected to the hard board are formed substantially in the same shape as that of land areas of the hard board within a range to be affected by surface tension of molten solder so that the tab portions tend to go into desired positions with the aid of self-alignment effect owing to the surface tension of molten solder, when the mounting member is mounted onto the hard board. 
   As can be seen from the above descriptions, the connector, the mounting member and the method for mounting the mounting member onto a hard board according to the invention can bring about the following significant functions and effects.
     (1) In a connector for connecting a flexible printed circuit board to a hard board, according to the invention, bump contacts are provided on contact portions of the flexible printed circuit board, and the flexible printed circuit board is formed with slits between two bump contacts, or between pairs of bump contacts, each pair consisting of two adjacent bump contacts, or between bump contacts arbitrarily selected so as to permit individual bump contacts to be independent of one another to provide compliance to the bump contacts sufficient to accommodate differences in height of the bump contacts. Therefore, the stable connection is obtained between the flexible and hard boards.   (2) According to the invention, a mounting member is arranged on the hard board, and the flexible printed circuit board is provided on the contact portions with bump portions and on the opposite side with an elastic member. A pusher member for urging the flexible printed circuit board and the elastic member is provided, and by engaging the pusher member with the mounting member, the connection of the flexible and hard boards is achieved. It becomes possible to obtain a connector with narrower pitches of contacts, occupying least space and flattened to less than 1 mm in thickness.   (3) As the flexible printed circuit board is directly forced against the hard board according to the invention, a connector flattened as much as possible can be obtained.   (4) According to the invention, two tab portions of the mounting member to be connected to the hard board is formed substantially in the same shape as that of land areas on the hard board within a range to be affected by surface tension of molten solder, thereby positioning the mounting member on the hard board with the aid of the self-alignment effect. Therefore, the mounting member can be easily arranged on the hard board with the aid of the self-alignment effect owing to the surface tension of the molten solder.   (5) According to the invention, the mounting member consists of the two tab portions integrally connected by a connecting member to form a unitary body. Therefore, the number of parts is decreased, and the positioning of the mounting member as one unitary body can be performed with less errors than two tab portions are positioning separately, so that the positioning of the mounting member on the hard board can be carried out more exactly.   (6) According to the invention, the hard board is provided with a plurality of circular lands and the mounting member is provided with exposed connecting portions having the same shape as that of the lands at location corresponding to the lands. Accordingly, the surface tension of molten solder is more easily produced to increase the self-alignment effect so that the mounting member can readily be fixed to the hard board by reflow soldering.   (7) According to the invention, the flexible printed circuit board and the elastic member are integrally fixed to each other such that the pusher member can be accurately held in a desired position relative to the mounting member when the pusher member is engaged with the mounting member. Therefore, such an integrally connected unit can be easily brought into a desired position to ensure the connection of the bump contacts of the flexible printed circuit board and pads of the hard board.   (8) According to the invention, the pushing portion of the pusher member consists of two members adhered together. Accordingly, the pusher member becomes stronger.   (9) According to the invention, the two members of the pusher member are made of the same material and different in thickness or shape, or the two members are made of different materials and also different in thickness or shape. With these constructions, the pusher member becomes stronger to ensure the reliable connection of the flexible printed circuit board to the hard board.   (10) According to the invention, one of the two members of the pusher member on the side of the elastic member is curved so that the force urging the pusher member to the mounting member is uniformly distributed. Therefore, uniform contact pressure can be obtained to ensure stable contact between the bump contacts of the flexible printed circuit board and the pads of the hard board.   (11) According to the invention, the pusher member is provided with the anchor portions bent into a U-shape at locations corresponding to the engaging portions of the mounting member. This construction will help to flatten the connector and miniaturize it in its width direction.   (12) According to the invention, the mounting member is provided with a plurality of mounting portions each having a tab portion and an engaging portion, and the plurality of mounting portions are integrally connected by a connecting member provided with at least one protrusion plate. With this construction, automatic mounting becomes possible without increasing production steps and management for installing, removing and discarding tapes and without increasing manufacturing cost and without causing potential environment deterioration.   (13) According to the method of the invention for mounting the mounting member on the hard board by soldering, the protrusion plate of the mounting member is sucked and the mounting member is arranged in position on the hard board, and thereafter the mounting member is fixed in desired position to the hard board by reflow soldering after that the protrusion plate is removed therefrom. According to this method, the automatic mounting becomes possible and the mounting member can be easily fixed to the hard board without increasing production steps and management for installing, removing and discarding tapes, without increasing manufacturing cost and without causing potential environment deterioration.   (14) According to the invention, the mounting member can be readily fixed to the hard board, resulting in that flattening of the connector is possible and manufacturing cost is reduced.   (15) According to the invention, the protrusion plate of the mounting member is formed so as to provide at least one clearance between the hard board and the protrusion plate at any portion of it, and the connecting portion between the protrusion plate and the connecting member is formed with at least one notch. Therefore, the protrusion plate can be easily removed from the mounting member after it has been fixed to the hard board by reflow soldering.   

   The invention will be more fully understood by referring to the following detailed specification and claims taken in connection with the appended drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view illustrating a pusher member, an elastic member and a flexible printed circuit board fixed to one another and a mounting member fixed to a hard board; 
       FIG. 2  is a perspective view similar to  FIG. 1 , but the flexible printed circuit board provided with slits between bump contacts; 
       FIG. 3  is a perspective view illustrating a flexible printed circuit board similar to that in  FIG. 1  but formed with slits between bump contacts; 
       FIG. 4  is a perspective view illustrating a flexible printed circuit board similar to that in  FIG. 2  but formed with slits between pairs of bump contacts; 
       FIG. 5  is a perspective view illustrating another pusher member and another mounting member fixed to a hard board; 
       FIG. 6  is a plan view illustrating the hard board and the mounting member viewed from the surfaces to be fixed to each other; 
       FIGS. 7A  to  7 E are explanatory views illustrating various pusher members each consisting of two members adhered together; 
       FIG. 8  is a perspective view illustrating a further pusher member and a further mounting member fixed to a hard board; 
       FIG. 9  is a perspective view of a pusher member, an elastic member and a flexible printed circuit board fixed to one another, and a mounting member fixed to a hard board before and after removal of the protrusion plate; 
       FIG. 10  is a perspective view similar to  FIG. 9  but illustrating different members; 
       FIG. 11  is a perspective view illustrating a mounting member having a protrusion plate fixed to a hard board and a pusher member; 
       FIG. 12  is a perspective view for explaining a state of fixing a mounting member to a hard board; 
       FIG. 13  is a perspective view illustrating a pusher member different from those shown in  FIGS. 9  to  12  and a mounting member fixed to a hard board; and 
       FIG. 14  is a perspective view of a pusher member, an elastic member and a flexible printed circuit board not having slits fixed to one another and a mounting member fixed to a hard board before and after removal of the protrusion plate. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   A connector according to the invention will be explained hereinafter. First, a flexible printed circuit board and a hard board and connection construction thereof will be explained. As shown in  FIG. 1 , the flexible printed circuit board  20  is provided with bump contacts  22  on respective contact portions  26  thereon. The flexible printed circuit board  20  is formed with slits  24  between bump contacts  22  as shown in  FIG. 2 , or between pairs of bump contacts  22 , each pair consisting of two adjacent bump contacts  22  as shown in  FIGS. 3 and 4 . The slits  24  make the bump contacts  22  between the slits  24  independent of the circuit board to obtain somewhat freedom of movement, thereby allowing slight deviation in height of the bump contacts  22 . In other words, complete contact of the bump portions  22  with mating contacts can be assured owing to the resulting compliance even if there are some deviations in height of the bump contacts  22 . 
   The shape and size of the slits  24  may be designed in consideration of the above functions. Although not shown, the slits  24  may be provided only between arbitrarily selected bump contacts  22 . So long as the required compliance can be obtained, slits  24  may be formed in any locations, for example, in every fourth space between bump contacts, or in every other space, every third space, every other space, every third space, and so forth. 
   A hard board  60  is provided with pads  64  in desired positions according to customer&#39;s specification or the like as shown in  FIGS. 1 ,  2  and  6 . Also provided on the hard board  60  are lands  62  for fixing a mounting member  40  discussed below. With the connector  10  according to the invention, the bump contacts  22  of the flexible printed circuit board  20  are adapted to be connected to the pads  64  of the hard board  60 . 
   The connector  10  of the illustrated embodiment mainly comprises the flexible printed circuit board  20 , an elastic member  50 , the mounting member  40  and a pusher member  30 . The connector  10  according to the invention is particularly intended to be thinned and space-saving connector. The connector  10  is adapted to be connected to the hard board. The respective components of the connector  10  will be explained hereinafter. 
   The mounting member  40  is substantially U-shaped as clearly shown in FIG.  5  and formed by known press-working from a metal. Metals for the mounting member  40  include brass, beryllium copper, phosphor bronze and the like to fulfil the requirements imposed thereon, springiness, workability, dimensional stability and the like. 
   The mounting member  40  is provided with two tab portions  42  at locations corresponding to the lands  62  of the hard board  60 . The shape of the tab portions  42  is substantially the same as that of the land areas surrounding by broken lines ( FIG. 6 ) within a range to be affected by surface tension of molten solder so that when the mounting member is mounted on the hard board  60  by reflow soldering, the former can readily be arranged in place to the latter with the aid of a self-alignment effect owing to the surface tension of the molten solder. In other words, the shape of the tab portions  42  is suitably designed so as to generate such a self-alignment effect by the molten solder. The fixation of the mounting member  40  in place to the hard board  60  ensures that the bump contacts  22  of the flexible printed circuit board  20  are securely connected to the pads  64  of the hard board  60  when the pusher member  30  is brought into engagement with the mounting member  40 . 
   The two tab portions  42  are connected by a connecting member  46  to each other to form a unitary construction. The shape and size of the connecting member  46  may be suitably determined in consideration of miniaturization and flatness of the connector and strength of the connecting member  46 . 
   Moreover, the tab portions  42  are provided with engaging portions  44  adapted to engage the pusher member  30 , respectively. Any size and shape of the engaging portions  44  may be employed so long as they can engage the pusher member  30  and may be determined in view of the miniaturization and flatness of the connector. In the illustrated embodiment, parts of the tab portions  42  are bent substantially vertically and the bent portions are provided with protrusions  49  adapted to engage the pusher member  30  as shown in FIG.  1 . The bent portions are preferably as small as possible to fulfil the requirement for connector to be flattened so long as they can engage the pusher member  30 . 
   A method for enhancing the self-alignment effect described above will be explained by referring to  FIG. 6  herein. As shown in  FIG. 6 , the hard board  60  is provided with five circular lands  62  in each of the land area surrounded by broken lines, while the mounting member  40  is provided with connection portions  48  at locations corresponding to the lands  62  of the hard board  60 . In providing the connection portions  48 , masking may be used, that is, the tab portions are covered by masks except for portions to be provided with the connection portions  48 . In this manner, the plurality of the circular lands  62  and the circular connection portions  48  will provide increased portions in which the surface tension of molten solder is exerted, with resulting increased self-alignment effect. 
   The flexible printed circuit board  20  will be explained. As described above, the circuit board  20  is provided with a required number of contact portions  26  positioned corresponding to the pads  64  on the hard board  60 , and the contact portions  26  are each provided thereon with a bump contact  22  adapted to contact with each pad  64  of the hard board  60 . As mentioned above, the slits  24  will give a compliance to the bump contacts  22  so as to accommodate deviations in height of the bump contacts  22 . Whether the slits are provided or not may be suitably determined depending upon spacing between adjacent terminals. In other words, the narrower the spacing is, the more preferable the slits are provided. 
   The elastic member  50  will then be explained. The elastic member  50  is provided to prevent the flexible printed circuit board  20  from being damaged when the bump contacts  22  on the flexible printed circuit board  20  are urged against the pads  64  of the hard board  60 . Materials for the elastic member  50  include silicone rubber, neoprene rubber and the like. The size of the plastic body  50  may be suitably determined in consideration of its function described above and miniaturization and flatness of the connector. Sufficient is the size capable of covering the contact portions  26  of the flexible printed circuit board  20 . The thickness of the elastic member of the order of 0.3 to 0.5 mm may be enough to absorb the compression force of the pusher member. 
   The pusher member  30  will then be explained. The pusher member  30  is substantially plate-shaped and formed by the known press-working from a metal. Preferred materials from which to form the pusher member  30  include brass, beryllium copper, phosphor bronze and the like in view of springiness, workability, dimensional stability and the like required for the pusher member  30 . 
   The pusher member  30  is provided with anchor portions  34  at locations corresponding to the engaging portions  44  of the tab portions  42  of the mounting member  40  to permit the anchor portions  34  to engage the engaging portions  44 . Any size and shape of the anchor portions  34  may be employed so long as they can engage the mounting member  40 . The anchor portions  34  may be suitably designed in consideration of miniaturization and flatness of the connector. In the illustrated embodiment, ends of the pusher member  30  are bent substantially perpendicular thereto to form bent portions on which the anchor portions  34  are provided. The size of the bent portions is preferably as small as possible within a range permitting the engagement with the engaging portion  44  of the mounting member  40  in consideration of miniaturization and flatness of the connector. 
   The pusher member  30  includes pushing portions  32  for pushing the elastic member  50  and hence the flexible printed circuit board  20 . The pushing portions  32  are designed so as to be able to force the flexible printed circuit board  20  against the hard board  60  when the pusher member  30  engages the mounting member  40 . Any size and shape of the pushing portions  32  may be employed so long as the flexible printed circuit board  20  can be urged against the hard board  60 . The pushing portions  32  may be suitably designed in consideration of miniaturization and flatness of the connector and strength of the pusher member  30 . In the illustrated embodiment, beading is applied to the surfaces of the pushing portions  32  in order to ensure the pushing action of the pusher member  30 . 
   The pusher member  30  is preferably formed of two members in order to increase its strength in spite of the fact that the total thickness is thinner (FIG.  7 ). The two members may be of the same material or different materials. In the case of different materials, preferably, one is an elongation-resistant material and the other a bending-resistant material. In a beneficial example, one member has a thickness thicker than the other as shown in  FIG. 7B  or  7 C. However, the maximum thickness should be limited to a value of the order of 0.3 mm in view of the flatness of the connector. 
   In the case that the pusher member  30  consists of two members, the member on the side of the elastic member  50  is preferably in the form of a curved shape as shown in  FIGS. 7D and 7E , with a view to uniformly distributing the force pushing the elastic member  50 . The degrees of curves are shown on an exaggerated scale in  FIGS. 7D and 7E . In  FIG. 7D , the anchor portions  34  are provided on the curved member, and in  FIG. 7E , the anchor portions  34  are provided on the straight member. 
     FIG. 5  illustrates a pusher member  30  and an mounting member  40  of another embodiment, which are substantially similar in construction to those above described. In  FIG. 5 , parts of the mounting member  40  are bent to form engaging portions  44 , while the pusher member  30  is formed with rectangular holes as anchor portions  34  correspondingly to the engaging portions  44  of the mounting member  40  so that the engaging portions  44  come into engagement with the rectangular holes  34  when the pusher member  30  is urged against the mounting member  40 . The pusher member  30  including the anchor portions  34  is elastic so that the pusher member  30  can easily be removed from the engagement with the mounting member  40 . In the same manner described above, fixed to the pusher member  30  are the elastic member  50  and the flexible printed circuit board  20 . 
     FIG. 8  illustrates a pusher member  30  and an mounting member  40  of a further embodiment which are substantially similar in construction to those shown in FIG.  5 . In the same manner as that in  FIG. 5 , parts of the mounting member  40  are bent to form engaging portions  44 , while the pusher member  30  is formed with rectangular holes as anchor portions  34  corresponding to the engaging portions  44  of the mounting member  40  so that the engaging portions  44  come into engagement with the rectangular holes  34  when the pusher member  30  is urged against the mounting member  40 . The pusher member  30  in  FIG. 5  is provided at both the ends with extension portions  34 ′ extending in width directions, to which a tool is applied for removing the pusher member  30  from the mounting member  40 . In  FIG. 8 , on the other hand, the pusher member  30  is provided at both the ends with U-shaped portions  34 ″, to which the tool is applied for the removal of the pusher member  30 . Other features of those shown in  FIG. 8  is the same as the features of those in FIG.  5 . 
   A method for assembling the connector  10  of the illustrated embodiment will be explained. First, the mounting member  40  is fixed in position onto the hard board  60  as by reflow soldering. Second, the pusher member  30 , the elastic member  50  and the flexible printed circuit board  20  are, in that order, integrally fixed to one another to form an integral unit such that when the pusher member  30  is engaged with the mounting member  40 , the pusher member  30  is accurately held in position relative to the mounting member  40 , and the flexible printed circuit board is also accurately positioned relative to the hard board. Next, the thus assembled integral unit is directed with its flexible printed circuit board  20  toward the mounting member  40  fixed to the hard board  60  and the pusher member  30  is then brought into engagement with the mounting member  40 , with the result that the bump contacts  20  of the flexible printed circuit board  20  come into contact with the pads  64  of the hard board  60 , thereby achieving electrical continuity between the connector  10  and the hard board  60 . 
   While the flexible printed circuit board formed with slits  24  for providing the compliance is explained in the above embodiment, it will be apparent that a flexible printed circuit board not having slits of course can also be used for the connector according to the invention. In the case particularly that the bump contacts are arranged with a large pitch or in a single row, the slits may not be provided. An example of a flexible printed circuit board not having slits is shown in  FIGS. 1 and 14 . 
   Another aspect of the invention will be explained by referring to  FIGS. 9  to  14  hereinafter. This aspect relates to a mounting member and a method for mounting the mounting member on a hard board. The connectors illustrated in  FIGS. 9  to  14  are substantially similar construction to those in  FIG. 1-8 , and therefore the same features of the components of the connectors to those in  FIGS. 1-8  will not be described in further detail. 
   Referring to  FIG. 9 , the connector  10  mainly comprises a flexible printed circuit board  20  having contact portions  26  and bump contacts  22  thereon, an elastic member  50 , a pusher member  30  and a mounting member  70 . The mounting member  70  is mounted on a hard board  60 , and the pusher member  30  having the flexible printed circuit board  20  and the elastic member  50  fixed to the pusher member  30  is brought into engagement with the mounting member  70  mounted on the hard board  60  so that the bump contacts  22  are urged against pads (not shown) on the hard board  60 , thereby achieving electrical continuity of the connector  10  in the same manner as in the connector  10  shown in FIG.  1 . 
   The flexible printed circuit board  20 , the elastic member  50  and the pusher member  30  are substantially same as those in  FIGS. 1-8  and therefore explanations as to these members will not be described. 
   The mounting member  70  will be explained in detail. The mounting member  70  is ultimately substantially in the form of U-shape, which is adapted to engage the pusher member  30  in the same manner as in the embodiments in  FIGS. 1-8 . The material and forming method for the mounting member  70  are substantially the same as those in  FIGS. 1-8 . 
   The mounting member  70  is provided with a plurality of mounting portions  76  each having a tab portion  72  at a location corresponding to the lands  62  ( FIG. 6 ) and an engaging portions  74  adapted to engage the pusher member  30 . The shape of the tab portions  72  is substantially the same as that of the land areas within a range to be affected by surface tension of molten solder, so that when the mounting member is mounted on the hard board  60 , the former can readily be position in place on the latter with the aid of a self-alignment effect owing to the surface tension of the molten solder. In other words, the shape of the tab portions  72  is suitably designed so as to generate such a self-alignment effect by the molten solder. The fixation of the mounting member  70  in place to the hard board  60  ensures that the bump contacts  22  of the flexible printed circuit board  20  are certainly connected to pads  64  of the hard board  60  when the pusher member  30  is brought into engagement with the mounting member  70 . 
   In order to enhance the self-alignment effect described above, the hard board  60  is provided with five circular lands  62  in each of the land areas shown in broken lines in  FIG. 6 , while the mounting member  70  is provided with connection portions  48  ( FIG. 6 ) at locations corresponding to the lands  62  of the hard board  60 . In this manner, the plurality of the circular lands and the circular connection portions will provide increased portion in which the surface tension of molten solder acts, with resulting increased self-alignment effect. 
   The plurality of the mounting portions  76  are connected by an connecting member  78  to form an integral unit.  FIGS. 9  to  12  illustrate the mounting members  70  each having two mounting portions  76 . The shape and size of the connecting member  78  are suitably designed in consideration of the miniaturization and flatness of the connector and strength of the connecting member  78 . 
   As described above, each of the mounting portions  76  includes the engaging portion  74 . Any size and shape of the engaging portions  74  may be employed so long as they can engage the pusher member  30  and they may be designed in view of the miniaturization and flatness of the connector. In the embodiments illustrated in  FIGS. 9  to  13 , part of each of the tab portions  72  is bent substantially vertically to form a vertical portion, and a small part of the vertical portion corresponding to the engaging portion  34  of the pusher member  30  is bent back to form an anchor portion  74 . The sizes of the vertical portions and the anchor portions  74  are preferably as small as possible to fulfil the requirement for the connector to be flattened so long as they can engage the pusher member  30 . 
   The connecting member  78  includes a protrusion plate  80  which is adapted to attach to the hard board  60  by suction caused by a suction mounter for automatically mounting the mounting member  70  on the hard board  60 . The shape and size of the protrusion plate  80  are suitably designed in consideration of capability to be sucked and attached to the hard board by the suction mounter, not being deformed when being sucked, and miniaturization and flatness of the connector. Preferably, the protrusion plate  80  has a thickness substantially equal to that of the mounting member  70  in view of easiness in working. 
   The protrusion plate  80  is removed after the mounting member  70  has been fixed to the hard board  60  by reflow soldering. In order to remove it from the mounting member  70  easily, the protrusion plate  80  is provided with at least one raised portion to provide a clearance  82  between the raised portion and the hard board  60 . In the illustrated embodiment, one corner of the protrusion plate  80  is slightly bent away from the hard board  60  to form a right angled triangular raised portion as shown in FIG.  9 . Moreover, the protrusion plate  80  is formed with notches  84  in its one side merging with the connecting member  78 . With this configuration, after the mounting member  70  has been fixed to the hard board  60  by reflow soldering, a tool is inserted into the clearance  82  between the raised portion and the hard board  60  to easily remove the protrusion plate  80  from the mounting member  70 . The size of the notches  84  may be suitably designed in consideration of strength of the mounting member  70  required for its automatic mounting and easiness in removing the protrusion plate  80  after reflow soldering. 
     FIG. 13  illustrates another pusher member  30  and another mounting member  70  which are substantially similar in construction to those described above. The mounting member  70  shown in  FIG. 13  is provided substantially at its mid portion of the connecting member  78  with a mounting portion  76  similar to mounting portions  76  at both the ends of the mounting member  70 . On the other hand, the pusher member  30  is provided at its mid portion with an anchor portion  34 , other than the anchor portions at both the ends, corresponding to the mounting portion  76  at the mid portions of the mounting member  70 . 
   The reason why such a mounting portion  76  is further provided at the mid portion of the pusher member  30  is that when the distance between the mounting portions  76  at both the ends of the mounting member  70  becomes longer, the force engaging the pusher member  30  with the mounting member  70  will become larger to cause the pusher member  30  to be deformed or warped so that it becomes difficult to maintain the contact between the bump contacts  22  of the flexible printed circuit board  20  and the pads  64  of the hard board  60  at the middle of both the members  30  and  70  with a sufficient force urging the center portions of these members to each other. The engagement of all the anchor portions  34  with all the mounting portions  76  of both the members  30  and  70  sufficiently prevent the pusher member  30  from being deformed to ensure the good contact between the bump contacts  22  and the pads  64  of both the boards  20  and  60 , thereby preventing any defective or failed connection between both the boards  20  and  60 . Mounting portions  76  may be provided at locations other than at the middle and both the ends depending on the force urging the pusher member  30  against the mounting member  70 . 
   Finally, a method for the mounting member  70  to the hard board  60  by reflow soldering will be explained.
     (1) First, the protrusion plate  80  of the mounting member  70  is sucked by means of a suction mounter.   (2) Second, the mounting member  70  is arranged in desired position on the hard board  60 .   (3) Third, the mounting member  70  is fixed to the hard board  60  by reflow soldering and thereafter the protrusion plate  80  is removed from the mounting member  70 .   (4) The pusher member  30  having the flexible printed circuit board  20  and the elastic member  50  fixed to the pusher member  30  is brought into engagement with the mounting member  70  thus fixed to the hard board  60  to complete the connector  10 .   

   While the invention has been particularly shown and described with reference to the preferred embodiments thereof, it will be understood by those skilled in the art that the foregoing and other changes in form and details can be made therein without departing from the spirit and scope of the invention.