Abstract:
A control unit having a package in which at least a part of components of a control system controlling specified controlling objects is housed, wherein a pair of protrusions is provided on each of opposite side surfaces of the package, and supporting members which operate as a vibration proof material are provided on each of opposite side surfaces of the package, wherein the pair of protrusions provided each of side surfaces of the package is fitted into a corresponding pair of holes of the supporting members to mount the supporting members on each of opposite side surfaces, and wherein transmission of vibration from the mounting portion to the package is prevented by mounting the package on the mounting portion through the supporting members.

Description:
TECHNICAL FIELD OF THE INVENTION  
       [0001]     This invention pertains to a control unit which comprises a control system or a part of the control system for controlling a specified control object of machines generating vibration such as an engine, a vehicle driven by an engine, or an engine generator.  
       BACKGROUND OF THE INVENTION  
       [0002]     In a control system for controlling a specified control object of machines generating vibration such as an engine, a vehicle driven by an engine, or an engine generator, at least a part of components of the control system is housed in a package consisting of resin molding or the like to construct a control unit, and the control unit is secured on a predetermined mounting portion provided on a part of the machine generating vibration.  
         [0003]     Since the control unit of this kind always receives vibration, a vibration proof material is mounted on the package in order to protect the components, and the package is secured to the mounting portion through the vibration proof material.  FIG. 6  shows a conventional control unit  1  of this kind. In this figure, a reference numeral  2  denotes a package which is formed so that the whole package shows a rectangular prism to house the components of the control system therein,  3  denotes a connector mounted on one side surface of the package  2 , and  4  denotes a tubular rubber cover mounted on the package  2  as a vibration proof material.  
         [0004]     The rubber cover  4  is formed into the shape of a duct, and a hole  4   a , which longitudinal both ends are opened, is formed inside of the rubber cover  4  as shown in  FIG. 7 . The rubber cover  4  is attached on an outer periphery of the package  2  by pressing the package  2  into the hole  4   a  of the rubber cover. Protrusions  403  and  404  extending in the longitudinal direction of the rubber cover  4  are provided on opposite side walls  401  and  402  of the rubber cover  4 , and slits  405  and  406  extending along the altitude direction of the rubber cover  4  are provided through the projections  403  and  404 .  
         [0005]     To fix the control unit shown in  FIG. 6  to a predetermined mounting portion, for example, a U-shaped mounting plate is fixed to the mounting portion, and opposite plate portions of the U-shaped mounting plate is fixed into the slits  405  and  406  of the rubber cover. A control unit of this kind is disclosed in, for example, Japanese Utility Model Application Laid-open Publication No. 62-87180.  
         [0006]     As shown in  FIG. 6 , since it is necessary to prepare different rubber covers specially designed for packages of different sizes when the tubular rubber cover is mounted on the package, increase in cost of the control unit was unavoidable  
         [0007]     Also, in order to prevent the control unit from coming out from the rubber cover, it is necessary to make a cross sectional area of the hole  4   a  of the rubber cover  4  smaller than that of the package  2  to fit the rubber cover into the outer periphery of the package. Thus, it is unavoidable that the manufacturing efficiency of the control unit lowers because of a troublesome procedure of fitting the package into the rubber cover  4 .  
       SUMMARY OF THE INVENTION  
       [0008]     Accordingly, it is a principal object of the invention to provide a control unit adapted to improve the manufacturing efficiency by simplifying attachment of a vibration proof material to a package.  
         [0009]     The present invention is applied to a control unit comprising at least a part of components of a control system controlling specified controlling objects and a package in which the components are contained, where the package is fixed at a mounting portion where vibrations may be transmitted.  
         [0010]     In the present invention, supporting members being consisted of an elastic material which are put in a vibration transmitting passage between the mounting portion and the package are mounted on opposite side surfaces of the package, respectively, and the package is constituted so as to be fixed on the mounting portion through the supporting members.  
         [0011]     The mounting of the supporting members to the side surfaces of the package can be performed easily by using suitable means such as adhesion, screwing and welding. Thus, if the supporting members being consisted of an elastic material are attached on each of opposite side surfaces to fix the package to the mounting portion through the supporting members as aforementioned, mounting of the vibration proof material becomes easier compared with the case where the package is fitted with the rubber cover, which causes improvement of the manufacturing efficiency of the control unit.  
         [0012]     Although the mounting of the supporting members to the side surfaces of the package can be performed easily by using suitable means such as adhesion, screwing and welding, it is preferable to mount the supporting members on the package with single operation in order to simplify assembling of the control unit.  
         [0013]     In a preferred mode of the invention, a pair of protrusions arranged with a space is provided on each of opposite side surfaces of the package. Also, there are provided supporting members being consisted of an elastic material and being formed with a pair of holes through which the above-mentioned one pair of protrusion is penetrated, and the pair of protrusion is fitted into the pair of holes of the supporting members so as to support the supporting member on the side surfaces of the package. On each tip portion of the protrusions which passes through each hole of the supporting members and is protruded outward, there are formed detents which engage with the periphery of the opening portions of the holes of the supporting members to seize the supporting members. By the seizure of the detents, the supporting members are supported so as not to be slipped off from the protrusions.  
         [0014]     With the aforementioned construction, since it is possible to mount the supporting members on the package with single operation, the assembling of the control unit can be easily performed, and thus the manufacturing efficiency of the control unit can be improved.  
         [0015]     As described above, according to the present invention, the supporting members being consisted of the elastic material are mounted on the opposite side surfaces of the package, respectively, and the package is fixed on the mounting portion through the supporting members. Therefore, the mounting of the vibration proof material becomes easier compared with the case where the package is fitted with the rubber cover, which causes improvement of the manufacturing efficiency of the control unit.  
         [0016]     Especially, in case that the pair of protrusion having the detents on the tip is provided on the side surfaces of the package to mount the supporting members on the package by fitting these protrusions into the holes being provided on the supporting members, the mounting of the supporting members on the package can be performed with single operation, the attachment of the supporting member can be simplified, and thus the manufacturing efficiency of the control unit can be improved. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0017]     The above and other objects and features of the invention will be apparent from the detailed description of the preferred embodiments of the invention, which is described and illustrated with reference to the accompanying drawings, in which;  
         [0018]      FIG. 1  is a plan view of a control unit in accordance with one embodiment of the invention, in a condition before supporting members are mounted on a package;  
         [0019]      FIG. 2  is a perspective view of the supporting members used in the embodiment of the invention;  
         [0020]      FIG. 3  is a front view of a control unit in accordance with the embodiment of the invention, where the supporting members are mounted on the package;  
         [0021]      FIG. 4A  illustrates a front view showing an example in a condition where the control unit in accordance with the present invention is mounted on a mounting portion through a mounting plate, and  FIG. 4B  illustrates a side view of the mounting plate used in this example;  
         [0022]      FIG. 5A  illustrates a front view showing an another example in a condition where the control unit in accordance with the present invention is mounted on a mounting portion through a mounting plate, and  FIG. 4B  illustrates a side view of the mounting plate used in this example;  
         [0023]      FIG. 6  shows a plan view of a conventional control unit; and  
         [0024]      FIG. 7  shows a perspective view of a rubber cover which is used as a vibration proof material in the conventional control unit. 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0025]     Now, the embodiments of the invention will be illustrated and described with reference to  FIGS. 1 through 5 B.  
         [0026]     In  FIGS. 1, 3 ,  4 A and  4 B, a reference numeral  12  denotes a package in a shape of a flat rectangle prism having: side surfaces  12   a  and  12   b  which are faced each other in the cross direction; side surfaces  12   c  and  12   d  which are faced each other in the longitudinal direction; and a bottom surface  12   e  and an upper surface  12   f  which are faced at a right angle relative to the opposite direction of the side surfaces  12   a  and  12   b  and the side surfaces  12   c  and  12   d . This package is made of a resin molding or the like. The package  12  contains all or a part of components of a control system (for example, an ECU) for controlling a specific control object such as an ignition system for and engine and a fuel injection system. On the side surface  12   c  at a longitudinal end of the package  12 , a connector  13  for connecting a circuit in the package to an outside circuit is attached.  
         [0027]     As shown in  FIG. 3 , there are mounted strip-shaped supporting members  16 ,  16  being consisted of elastic material such as rubber on the side surfaces  12   a  and  12   b  faced each other in the cross direction of the package. As shown in  FIG. 2 , holes  16   a  and  16   b  passing through the supporting member in the thickness direction are formed around longitudinal both ends of the supporting member  16 , and a slit  16   c  passing through the supporting members  16  in the cross direction is formed between the holes  16   a  and  16   b.    
         [0028]     The supporting members  16 ,  16  are attached in a condition where each longitudinal direction and cross direction of the supporting members is directed toward each longitudinal direction (X-X′ direction in  FIGS. 1 and 3 ) and thickness direction (the direction perpendicularly intersecting with drawing sheets showing  FIGS. 1 and 3 ) respectively to contact the end surface  16   d  on one end side in the thickness direction with the opposite side surfaces  12   a  and  12   b  of the package  12 .  
         [0029]     Each slit  16   c  of the supporting members  16  is provided so as to extend in the perpendicular direction (the altitude direction of the package) relative to the bottom surface  12   e  and the upper surface  12   f  while the both supporting members are mounted on the package  12 .  
         [0030]     In order to mount the supporting members, a pair of protrusions  14   a  and  14   b  being arranged with a space P in the longitudinal direction of the package is formed on each of the side surfaces  12   a  and  12   b  which are opposed in the cross direction of the package  12 . On tips of the protrusions  14   a  and  14   b , there are formed detents  14   a   1  and  14   b   1  protruded outward from each one end of the cross direction of the protrusions.  
         [0031]     The pair of the protrusions  14   a  and  14   b  on each side surface of the package is fitted into the pair of holes  16   a  and  16   b  of the supporting member  16 , the supporting members  16  are supported by the fitting of the holes  16   a ,  16   b  and the protrusions  14   a ,  14   b . Also, the detents  14   a   1  and  14   b   1 , which are formed on each tip portion of the pair of protrusions  14   a  and  14   b  protruded outward while passing through each of the pair of holes of the supporting members, engage with the periphery of the opening of the holes  16   a  and  16   b  to seize the supporting member  16 , which prevents the supporting members from coming out from the protrusions  14   a  and  14   b.    
         [0032]     When the control unit of the present invention is set to a mounting portion, a bottom plate  20   a  of a U-shape mounting plate  20  having the bottom plate  20   a  and side plates  20   b ,  20   c  is fixed to a mounting surface of the mounting portion  21 ; then, the side plates  20   b ,  20   c  of the mounting plate are fitted with the slits  16   c ,  16   c  of the supporting members  16 ,  16  mounted on the opposite surfaces  12   a  and  12   b  of the package, respectively, in order to unite the supporting members  16  and the mounting plate  20 .  
         [0033]     In this case, parts for receiving the supporting members  16  at a position apart from the mounting surface of the mounting portion  21  are provided on the side plates  20   b  and  20   c  of the mounting plate  20  so as to support the package  12  through the supporting members  16 , in a state where the bottom surface  12   e  of the package is opposed to the bottom plate  20   a  of the mounting plate  20  through a predetermined gap G. In the example shown in  FIG. 4B , width of lower parts, near the bottom plate  20   a , of the side plates  20   b  and  20   c  are enlarged to form steps  20   b   1  and  20   c   1  between the enlarged parts and the other parts of side plates  20   b  and  20   c . The supporting members  16 ,  16  are received by steps  20   b   1  and  20   c   1  of the side plates  20   b  and  20   c , and the bottom surface  12   e  of the package  12  is come up from the bottom plate  20   a  of the mounting plate  20  so as to from the gap G between the bottom surface  12   e  and the bottom plate  20   a . Also, the size of width of the tips of the side plate  20   b  and  20   c  arranged in a condition penetrating from the end portion opposed to the mounting portion of the supporting members  16  is slightly enlarged to form seizing portions  20   b   2  and  20   c   2  so that the package  12  does not come off from the side plates  20   b  and  20   c  of the mounting plate.  
         [0034]     As shown in  FIG. 5B , instead of forming the parts for receiving the supporting members  16 ,  16  on the side plates  20   b  and  20   c  as stated above, the package  12  may be fixed to the mounting portion  21  by inserting side plates  20   b ′ and  20   c ′ of a mounting plate  20 ′ into the slits of the supporting members  16 ,  16 , while end portions of the supporting members  16  which are opposed to the mounting portion  21  are deviated from the end portions of the package  12  toward the mounting portion  21  as shown in  FIG. 5A  so as to fix the package  12  to the mounting portion  21  in the condition that the bottom surface  12   e  of the package comes up from a bottom plates  20   a ′ of the mounting plate  20 ′. Also, in this case, the size of width of the tips of the side plate  20   b ′ and  20   c ′ arranged in a condition penetrating from the end portion opposed to the mounting portion of the supporting members  16  is slightly enlarged to form seizing portions  20   b   2 ′ and  20   c   2 ′ so that the package  12  does not come off from the side plates  20   b  and  20   c  of the mounting plate.  
         [0035]     As aforementioned, it is possible to prevent vibration from transmitting from the mounting portion to the package, since the supporting members  16 ,  16  are put in a vibration transmitting passage from the mounting portion to the package when the supporting members  16 ,  16  being consisted of a elastic material are mounted on opposite side surfaces of the package  12 , respectively, to fix the package  12  on the mounting portion  21  through the supporting members. Therefore, in case of mounting a control unit on a machine on which a vibration source such as an engine is provided, a damage of components, which is caused by large vibration transmitted to the components of the control unit, can be prevented.  
         [0036]     In addition, when the supporting members  16 ,  16  being consisted of the elastic material are mounted on the opposite side surfaces of the package  12 , respectively, as vibration proof material, the mounting of the vibration proof material becomes easier compared with a case where the package is fitted with the rubber cover, which causes improvement of manufacturing efficiency of the control unit.  
         [0037]     Especially, in case that the pair of protrusion  14   a  and  14   b  having the detents on the tip is provided on the side surfaces of the package to mount the supporting members on the package by fitting these protrusions into the holes  16   a  and  16   b  being provided on the supporting members  16  as described in the above embodiment, the mounting of the supporting members  16  on the package  12  can be performed with a single operation, the attachment of the supporting member can be simplified, and thus the manufacturing efficiency of the control unit can be improved.  
         [0038]     In case that the size of the package varies, the same supporting members can be used if a distance P (refer to  FIG. 1 ) between the protrusions  14   a  and  14   b  is identical. Thus, reduction in cost can be made by standardizing supporting members for control units of different specifications.  
         [0039]     Although some preferred embodiments of the invention have been described and illustrated with reference to the accompanying drawings, it will be understood by those skilled in the art that they are by way of examples, and that various changes and modifications may be made without departing from the spirit and scope of the invention, which is defined only to the appended claims.