Abstract:
In a brake hydraulic controller for controlling a hydraulic pressure from a master cylinder operative to a wheel brake, the controller includes a base, a normally open electromagnetic valve for connecting the master cylinder and the wheel brake, a reservoir, a normally closed electromagnetic valve for connecting the wheel brake and the reservoir, a return pump for returning hydraulic fluid received from the reservoir to the master cylinder, a damper, and a cover for covering the normally open and closed electromagnetic valves, the reservoir, and the damper with a surface of the cover. The cover includes a seal groove and a sealing member fitted to the seal groove for elastically contacting the surface. The brake hydraulic controller can minimize the number of parts required for waterproofing and reduce the number of manhours required for assembling.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a brake hydraulic controller including normally open electromagnetic valves interposed between a master cylinder and wheel brakes, reservoirs, normally closed electromagnetic valves interposed between the wheel brakes and the reservoirs, return pumps for returning hydraulic fluid from the reservoirs to the master cylinder, dampers interposed between the master cylinders, and a common base which disposes all of the above described elements. 
     A conventional brake hydraulic controller of this type has already been disclosed in Unexamined Japanese Patent Publication No. Hei. 7-9970. In this brake hydraulic controller, normally opened electromagnetic valves and normally closed electromagnetic valves are mounted on one side of the base, and reservoirs are mounted on another side of the base. A cover having a sealing member is fitted to the base so as to render the normally opened electromagnetic valves and the normally closed electromagnetic valves waterproof and dustproof. 
     In the above described conventional brake hydraulic controller, the reservoirs are attached to the base with some of them uncovered. The formation of rust on the uncovered portion of the reservoirs resulting from exposure to water is not prevented. It is only necessary to cover the reservoirs with a cover having a sealing member in order to prevent the reservoirs from rusting away. As previously described, the reservoirs are mounted on the side of the base which is different from the side on which the normally closed electromagnetic valves and the normally open electromagnetic valves are mounted. For this reason, it is necessary to cover the reservoirs with another cover, which results in the number of components and the number of manhours to fit a reservoir cover to the base being increased. 
     SUMMARY OF THE INVENTION 
     The present invention has been made in view of the conventional problems, and an object of the present invention is to provide a brake hydraulic controller in which a structure for rendering normally opened electromagnetic valves, normally closed electromagnetic valves, reservoirs, and dampers waterproof is formed with a few number of components, and in which the number of manhours needed to assemble the waterproof structure is reduced. 
     The object of the invention is achieved, according to a first aspect of the present invention, by a brake hydraulic controller for controlling a hydraulic pressure from a master cylinder operative to a wheel brake, in which the controller includes a base, a normally open electromagnetic valve mounted on the base for connecting the master cylinder and the wheel brake, a reservoir mounted on the base, a normally closed electromagnetic valve mounted on the base for connecting the wheel brake and the reservoir, a return pump mounted on the base for returning hydraulic fluid received from the reservoir to the master cylinder, a damper mounted on the base and connected to the master cylinder and the return pump, and a cover attached to the base for covering the normally open and closed electromagnetic valves, the reservoir, and the damper with a surface of the cover, the cover including a seal groove and a sealing member fitted to the seal groove for elastically contacting the surface. 
     In addition to the elements as described in the first aspect of the present invention, a brake hydraulic controller according to a second aspect of the present invention is characterized by the fact that the cover is made from synthetic resin; the seal grooves are formed in a substantially U-shaped cross section and is made up of an innermost closed surface and a pair of side surfaces connected to both sides of the innermost closed surface substantially at right angles; and the cover includes a reinforcing member which is made of rigid material so as to form at least one of the innermost closed surface and the pair of side surfaces. 
     In addition to the elements as described in the second aspect of the present invention, a brake hydraulic controller according to a third aspect of the present invention is characterized by the fact that the reinforcing member is embedded in the cover. 
     In addition to the elements as described in the third aspect of the present invention, a brake hydraulic controller according to a fourth aspect of the present invention is characterized by the fact that a cylindrical portion is integrally formed in the reinforcing member while one end of the cylindrical portion abuts against the surface of the base; and a lock head of a fastening bolt which is screwed to the base through the cylindrical portion is engaged with the other end of the cylindrical portion. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a circuit diagram of a hydraulic circuit of a vehicle brake control system according to a first embodiment of the present invention; 
     FIG. 2 is a partially cutaway side view of a brake hydraulic controller; 
     FIG. 3 is a front view of the brake hydraulic controller as viewed in the direction of an arrow III shown in FIG. 2; 
     FIG. 4 is a front view of a base taken along line IV—IV shown in FIG. 2; 
     FIG. 5 is a bottom view of a cover taken along line V—V shown in FIG. 2; 
     FIG. 6 is an enlarge view of an area VI shown in FIG. 2; 
     FIG. 7 is a cross-sectional view of the cover taken along line VII—VII shown in FIG. 5; 
     FIG. 8 is an exploded perspective view of a sealing member, a grommet, and the cover; 
     FIG. 9 is a perspective view of a vehicle brake hydraulic controller, according to a second embodiment, which is similar to FIG. 8; 
     FIG. 10 is a cross-sectional view of a vehicle brake hydraulic controller, according to a third embodiment, which is similar to FIG. 6; 
     FIG. 11 is a cross-sectional view of the vehicle brake hydraulic controller, according to the third embodiment, which is similar to FIG. 7; 
     FIG. 12 is a cross-sectional view of a vehicle brake hydraulic controller, according to a fourth embodiment, which is similar to FIG. 7; and 
     FIG. 13 is a cross-sectional view of the vehicle brake hydraulic controller, according to the fourth embodiment, which is similar to FIG.  7 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     With reference to the accompanying drawings, illustrative embodiments of the present invention will now be described. 
     FIGS. 1 through 8 show a brake hydraulic controller according to a first embodiment of the present invention. In FIG. 1, a tandem type master cylinder M is equipped with a pair of output ports  13   1 ,  13   2  for producing a hydraulic braking pressure corresponding to the degree of depression of a brake pedal P. A brake hydraulic controller  15  is interposed between a proportional pressure reducing valve  14   R  connected to a front left wheel brake B FL  and a rear right wheel brake B RR  and a hydraulic passage  12   1  connected to the output port  13   1 , and between a proportional pressure reducing valve  14   L  connected to a front right wheel brake B FR  and a rear left wheel brake B RL  and a hydraulic passage  12   2  connected to the output port  13   2 , respectively. 
     The brake hydraulic controller  15  includes four normally opened electromagnetic valves V OFL , V ORR , V ORF , and V ORL  respectively corresponding to the front left wheel brake B FL , the rear right wheel brake B RR , the front right wheel brake B FR , and the rear left wheel brake B RL ; four check valves  17   FL ,  17   RR ,  17   FR , and  17   RL  connected in parallel to the normally open electromagnetic valves V OFL , V ORR , V ORF , and V ORL ; four normally closed electromagnetic valves V CFL , V CRR , V CRF , and V CRL  respectively corresponding to the wheel brakes B FL , B FR , B RL , and B RR ; a pair of reservoirs  19   1 ,  19   2  respectively corresponding to the pair of front left wheel brake B FL  and rear right wheel brake B RR  and the pair of front right wheel brake B FR  and rear left wheel brake B RL ; a pair of reciprocating plunger pumps  21   1 ,  21   2  connected to the reservoirs  19   1 ,  19   2  via return pumps  20   1 ,  20   2 ; a single motor  22  shared between the reciprocating plunger pumps  21   1 ,  21   2 ; a pair of dampers  24   1 ,  24   2  connected to the reciprocating plunger pumps  21   1 ,  21   2  via outlet valves  23   1 ,  23   2 ; and orifices  25   1 ,  25   2  respectively interposed between the hydraulic passage  12   1  connected to the output port  13   1  of the master cylinder M and the dampers  24   1  and between the hydraulic passage  12   2  connected to the output port  13   2  Of the master cylinder M and the damper  24   2 . The demagnetization and excitation of the normally open electromagnetic valves V OFL , V ORR , V ORF , V ORL  and the normally closed electromagnetic valves V CFL , V CRR , V CRF , V CRL  are switchably controlled by an electronic control unit  26 . 
     The normally open electromagnetic valve V OFL  is interposed between the hydraulic passage  12   1  connected to the output port  13   1  of the master cylinder M and the front left wheel brake B FL ; the normally open electromagnetic valve V ORR  is interposed between the hydraulic passage  12   1  and the proportional pressure reducing valve  14   R  connected to the rear right wheel brake B RR ; the normally open electromagnetic valve V ORF  is interposed between the hydraulic passage  12   2  connected to the other output port  13   2  of the master cylinder M and the front right wheel brake B FR ; and the normally open electromagnetic valve V ORL  is interposed between the hydraulic passage  12   2  and the proportional pressure reducing valve  14   L  connected to the rear left wheel brake B RL . The check valves  17   FL ,  17   RR ,  17   FR , and  17   RL  are connected in parallel to the normally open electromagnetic valves V OFL , V ORR , V ORF , and V ORL  SO as to permit the flow of only hydraulic fluids flowing from the corresponding wheel brakes B FL , B FR , B RL , and B RR . 
     The normally closed electromagnetic valve V CFL  is interposed between the front left wheel brake B FL  and the reservoirs  19   1 ; the normally closed electromagnetic valve V CRR  is interposed between the proportional pressure reducing valve  14   R  and the reservoirs  19   1 ; the normally closed electromagnetic valve V CFR  is interposed between the front right wheel brake B FR  and the reservoirs  19   2 ; and the normally closed electromagnetic valve V CRL  is interposed between the proportional pressure reducing valve  14   L  and the reservoirs  19   2 . 
     With the brake hydraulic controller  15  having the above described configuration, the normally open electromagnetic valves V OFL , V ORR , V ORF , and V ORL  are in demagnetized and open conditions, and the normally closed electromagnetic valves V CFL , V CRR , V CRF , and V CRL  are in demagnetized and closed conditions during normal braking in which there is a low risk of locking of the wheels. Hence, the hydraulic braking pressure output from the output port  13   1  of the master cylinder M acts on the rear right wheel brake B RR  via the normally open electromagnetic valve V ORR  and the proportional pressure reducing valve  14   R  as well as on the front left wheel brake B FL  via the normally open electromagnetic valve V OFL . Further, the hydraulic braking pressure output from the output port  13   2  of the master cylinder M acts on the rear left wheel brake B RL  via the normally open electromagnetic valve V ORL  and the proportional pressure reducing valve  14   L  as well as on the front right wheel brake B FR  via the normally open electromagnetic valve V OFR . 
     During anti-lock braking carried out when a wheel becomes apt to lock as a result of braking, the normally open electromagnetic valve of the normally open electromagnetic valves V OFL , V ORR , V ORF , and V ORL  corresponding to the wheel which is likely to lock is closed, whereas the normally closed electromagnetic valve of the normally closed electromagnetic valves V CFL , V CRR , V CRF , and V CRL  corresponding to that wheel is opened. In consequence, a part of the hydraulic braking pressure escapes to the reservoir  19   1  or  19   2 , so that the hydraulic braking pressure is depressurized. In order to hold the hydraulic braking pressure, it is only necessary to demagnetize the normally closed electromagnetic valves V CFL , V CRR , V CRF , V CRL  so as to be held in a closed condition as well as to excite the normally open electromagnetic valves V OFL , V ORR , V ORF , and V ORL  so as to close. On the other hand, in order to increase the hydraulic braking pressure, it is only necessary to demagnetize the normally closed electromagnetic valves V CFL , V CRR , V CRF , V CRL  so as to be held in a closed condition as well as to demagnetize the normally open electromagnetic valves V OFL , V ORR , V ORF , and V ORL  so as to open. 
     The motor  22  for commonly driving the pair of plunger pumps  21   1 ,  21   2  is activated during the anti-lock braking. The hydraulic fluid which escaped to the reservoirs  19   1  and  19   2  returns in an upstream direction with respect to the normally open electromagnetic valves V OFL , V ORR , V ORF , and V ORL , that is, the hydraulic passages  12   1 ,  12   2 , from the plunger pumps  21   1 ,  21   2  via the dampers  24   1 ,  24   2  and the orifices  25   1 ,  25   2 . Hence, the degree of depression of the brake pedal P caused by the master cylinder M does not increase in proportion to the amount of the hydraulic braking pressure escaped to the reservoirs  19   1  and  19   2 . Further, pulsations of the hydraulic fluid flowing from the plunger pumps  21   1 ,  21   2  are attenuated by the action of the dampers  24   1 ,  24   2  and the orifices  25   1 ,  25   2 , so that pulsations of the brake pedal P are attenuated. 
     The electronic control unit  26 , which controls the demagnetization and excitation of the normally open electromagnetic valves V OFL , V ORR , V ORF , and V ORL  and the normally closed electromagnetic valves V CFL , V CRR , V CRF , V CRL , receives signals from wheel speed sensors  27   FL ,  27   RR ,  27   FR , and  27   RL  which respectively detect the speed of the wheels in order to check whether or not the wheels are likely to lock. Further, the electronic control unit  26  receives a signal from a hand brake sensor  29  which checks whether or not a hand brake  28  is actuated. Moreover, the electronic control unit  26  is connected to an alarm  30 , such as a lamp, which is activated by the electronic control unit  26  when the wheel is in the antilock braking condition. 
     Referring to FIG. 1 in conjunction with FIG. 2, the elements forming the brake hydraulic controller  15  are mounted on a block-shaped metal base  34  in which the elements are the four normally open electromagnetic valves V OFL , V ORR , V ORF , and V ORL , the four check valves  17   FL ,  17   RR ,  17   FR , and  17   RL , the four normally closed electromagnetic valves V CFL , V CRR , V CRF , and V CRL , the pair of reservoirs  19   1 ,  19   2 , the pair of return pumps  20   1 ,  20   2 , the pair of plunger pumps  21   1 ,  21   2 , the motor  22 , the pair of outlet valves  23   1 ,  23   2 , the pair of dampers  24   1 ,  24   2 , and the pair of orifices  25   1 ,  25   2 . 
     The base body  34  has a pair of opposite faces, that is, a face  34   a  and a face  34   b . The base body  34  is supported on a bracket  32 , which is mounted on a vehicle body  31 , by a plurality of mounting devices  33  in such a way that both faces  34   a  and  34   b  are faced to each other in the vertical direction. 
     Referring to FIGS. 3 and 4, four engaging recesses  35   FL ,  35   RR ,  35   FR , and  35   RL  and four engaging recesses  36   FL ,  36   RR ,  36   FR , and  36   RL  are formed in the face  34   a  of the base  34  in parallel to each other. Further, two reservoir recesses  37   1 ,  37   2  and two damping recesses  38   1 , and  38   2  are also formed in the face  34   a  in parallel to the above described engaging recesses in such a way as to have the following correspondence between them: namely, the reservoir recess  37   1  is placed in line with the engaging recesses  35   FL ,  36   FL ; the damping recess  38   1  is placed in line with the engaging recesses  35   RR ,  36   RR ; the reservoir recess  37   2  is placed in line with the engaging recesses  35   RL ,  36   RL ; and the damping recess  38   2  is placed in line with the engaging recesses  35   FR ,  36   FR . Further, lightening recesses  39 ,  40 ,  41 , and  42  are formed in the face  34   a  so as to have the following position relationship with respect to the above described elements; namely, the lightening recess  39  is surrounded by the engaging recesses  35   FL ,  35   RR ,  36   FL , and  36   RR ; the lightening recess  40  is surrounded by the engaging recesses  35   RR ,  35   RL ,  36   RR , and  36   RL ; the lightening recess  41  is surrounded by engaging recesses  35   RL ,  35   FR ,  36   RL , and  36   FR ; and the lightening recess  42  is surrounded by the engaging recesses  36   RR ,  36   RL  and the damping recesses  38   1 ,  38   2 . 
     As described above, the face  34   a  of the base  34  includes the four normally open electromagnetic valves V OFL , V ORR , V ORF , and V ORL , the four normally closed electromagnetic valves V CFL , V CRR , V CRF , and V CRL , the pair of reservoirs  19   1 ,  19   2 , and the pair of dampers  24   1 ,  24   2 . The motor  22  is mounted on the other face  34   b  of the base  34 , and the pair of plunger pumps  21   1 ,  21   2  driven by the motor  22  are incorporated in the base  34 . 
     The normally open electromagnetic valves V OFL , V ORR , V ORF , and V ORL  are fitted into the corresponding engaging recesses  35   FL ,  35   RR ,  35   FR , and  35   RL  such that each half of these normally open electromagnetic valves protrude from the face  34   a . Similarly, the normally closed electromagnetic valves V CFL , V CRR , V CRF , and V CRL  are fitted into the corresponding engaging recesses  36   FL ,  36   RR ,  36   FR , and  36   RL  such that each half of these normally open electromagnetic valves protrude from the face  34   a.    
     As shown in FIG. 2, the reservoir  19   2  includes a reservoir chamber  43  formed between the closed end face of the reservoir recess  37   2  and a piston  44  which is fitted into the reservoir recess  37   2  in a slidable fashion; an annular closure  45  fixedly fitted around the open end of the reservoir recess  37   2 ; and a return spring  46  compressedly interposed between the closure  45  and the piston  44 . The reservoir  19   1  is principally the same as the  19   2  in construction, and it is housed in the reservoir recess  37   1 . 
     The dampers  24   1 ,  24   2  are housed in the damping recesses  38   1 ,  38   2 , and each of the open ends of the damping recesses is sealed with a plug (not shown) in a fluid-tight manner. 
     With reference to FIGS. 5 and 6, a plastic cover  47  is attached to the surface  34   a  of the base  34  so as to cover the normally open electromagnetic valves V OFL , V ORR , V ORF , and V ORL , the normally closed electromagnetic valves V CFL , V CRR , V CRF , V CRL , the reservoirs  19   1 ,  19   2 , the dampers  24   1 ,  24   2 , and the lightening recesses  39  to  42 . 
     A seal groove  48   1  having a substantially U-shaped cross section is formed along the entire circumference of the side of the cover  47  that faces the face  34   a . The seal groove  48   1  is made up of an innermost closed surface  49   1  and a pair of side surfaces  50   1 ,  51   1  connected to both sides of the innermost closed surface  49   1  substantially at right angles. A sealing member  52   1  which is fitted in the seal groove  48   1  is elastically brought into contact with the face  34   a . As a result, it possible to prevent the entry of water or dust into the cover  47 . 
     The seal groove  48   1  includes a recess formed along the inner edge of the side of the cover  47  that faces the face  34   a , and a reinforcing member  54   1  which is embedded in the cover  47  and is made of rigid material. The reinforcing member  54   1  includes a support plate  55   1  which extends substantially in parallel with the face  34   a  and is embedded in the cover  47 , and a side portion  56   1  which is connected to the inner edge of the support plate  55   1  at substantially right angles. The reinforcing member  54   1  has a substantially L-shaped cross section. The support plate  55   1  is embedded in the cover  47  to be spaced apart from the innermost closed surface  49   1  formed in the cover  47 . The side portion  56   1  forms the side surface  50   1  of the two side surfaces  50   1 ,  51   1 , and the side portion  56   1  is connected to the support plate  55   1 . 
     As shown in FIG. 4, screw holes  60   1 ,  60   1  are formed in the vicinity of the outer periphery of the face  34   a  of the base  34 , and screw holes  60   2 ,  60   2  are formed in the face  34   a  in the vicinity of the reservoir and damping recesses; more specifically, the screw hole  60   1  is formed in the vicinity of the outer periphery defined between the engaging recesses  35   FL  and  35   RR ; the screw hole  60   1  is formed in the vicinity of the outer periphery defined between the engaging recesses  35   RL  and  35   FR ; the screw hole  60   2  is formed to be surrounded by the engaging recesses  36   FL ,  36   RR , the reservoir recess  37   1 , and the damping recess  38   1 ; and the screw hole  60   2  is formed to be surrounded by the engaging recesses  36   RL ,  36   FR , the reservoir recess  37   2  and the damping recess  38   2 . 
     The support plate  55   1  of the reinforcing member  54   1  includes an extended plate  57   1  extending outwardly at a portion corresponding to the screw holes  60   1 , as shown in FIG.  7 . The support plate  55   1  includes a cylindrical projection  58   1  having one end brought into contact with the face  34   a  at the portion corresponding to the screw holes  60   1  and the other end integrally formed in the extended plate  57   1 . A fastening bolt  61  to be screwed into the screw hole  60   1  is inserted into each cylindrical projection  58   1 . A lock head  61   a  of the fastening bolt  61  engages with the base side of the cylindrical projection  58   1 , that is, the extended plate  57   1 . The cover  47  includes arms  59   1 ,  59   1  which cover the extended plates  57   1 ,  57   1  and the cylindrical projections  58   1 ,  58   1  in order to make it possible to insert the fastening bolts  61  into the cylindrical projections  58   1 ,  58   1  from above as well as to engage the lock head  61   a  of the fastening bolt  61  with the base side of the cylindrical projections  58   1 ,  58   1 . 
     Cylindrical sleeves  62 ,  62  (FIG. 5) are integrally embedded in the cover  47  corresponding to the screw holes  60   2 ,  60   2  of the base  34 . The fastening bolts  61 ,  61  are screwed into the screw holes  60   2 ,  60   2  via the sleeves  62 ,  62 . 
     As shown in FIG. 3, electrical wires  63 ,  63 , which are respectively connected to the normally open electromagnetic valves V OFL , V ORR , V ORF , V ORL  and the normally closed electromagnetic valves V CFL , V CRR , V CRF , V CRL , are tied into a wire harness  64 , and the wire harness  64  is led out of the cover  47 . A grommet  53   1  for sealing the space between the wire harness  64  and the cover  47  is integrated with the sealing member  52   1 , as shown in FIG.  8 . The grommet  53   1  is fitted into a notch  47   a  formed in the cover  47 . 
     The operation of the brake hydraulic controller of the first embodiment will now be described. The normally open electromagnetic valves V OFL , V ORR , V ORF , V ORL , the normally closed electromagnetic valves V CFL , V CRR , V CRF , V CRL , the reservoirs  19   1 ,  19   2 , and the dampers  24   1 ,  24   2  are mounted on the face  34   a  of the base  34 . The sealing member  52   1  which elastically comes into contact with the face  34   a  is fitted in the cover  47  which is attached to the face  34   a  of the base  34  so as to cover the normally open electromagnetic valves V OFL , V ORR , V ORF , V ORL , the normally closed electromagnetic valves V CFL , V CRR , V CRF , V CRL , the reservoirs  19   1 ,  19   2 , and the dampers  24   1 ,  24   2 . 
     In short, the normally open electromagnetic valves V OFL , V ORR , V ORF , V ORL , the normally closed electromagnetic valves V CFL , V CRR , V CRF , V CRL , the reservoirs  19   1 ,  19   2 , and the dampers  24   1 ,  24   2  are prevented from being exposed to water by the single cover  47  and the sealing member  52   1 , which makes it possible to prevent electrical leakage and rust. In consequence, the number of parts required to render the normally open electromagnetic valves V OFL , V ORR , V ORF , V ORL , the normally closed electromagnetic valves V CFL , V CRR , V CRF , V CRL , the reservoirs  19   1 ,  19   2 , and the dampers  24   1 ,  24   2  waterproof is minimized, which makes it possible to reduce the number of parts of the brake hydraulic controller. It is also possible to reduce the number of manhours required to mount the above described elements to the base  34 . 
     In the reservoirs  19   1 ,  19   2 , there is a concern about obstruction of the smooth movement of the piston  44  in response to the inflow of the hydraulic fluid into the reservoir chamber  43  and the outflow of the hydraulic fluid from the same while the space outside the piston  44  is hermetically closed. Since the cover  47  covers all of the normally open electromagnetic valves V OFL , V ORR , V ORF , V ORL , the normally closed electromagnetic valves V CFL , V CRR , V CRF , V CRL , the reservoirs  19   1 ,  19   2 , and the dampers  24   1 ,  24   2 , the volume of the space enclosed by the cover  47  becomes relatively large. Variations in the pressure within the cover  47  caused as a result of the movement of the piston  44  are suppressed to a small level, which in turn assures the smooth movement of the piston  44 . If the cover is designed to cover only the reservoirs, the volume of the space in the cover has to become relatively small. As a result, variations in the pressure within the cover become larger, which results in the risk of obstruction of the smooth movement of the piston. 
     If the seal groove in which the sealing member  52   1  is fitted is directly formed in the plastic cover  47 , a relatively large load acts on the side of the seal groove resulting from the clamping of the cover  47  and the base together. As a result, the side of the seal groove is deformed, which makes it impossible to ensure sufficient sealing performance of the sealing member. In the first embodiment, the seal groove  48   1  includes the innermost closed surface  49   1  and the side surfaces  50   1 ,  50   2  attached to the respective sides of the innermost closed surface  49   1 . Further, of the side surfaces  50   1 ,  51   1 , the side surface  50   1  is made by the side surface  56   1  of the reinforcing member  54   1  which is formed from a rigid material and is embedded in the cover  47 . In this way, the side surface  50   1  has sufficient strength, and the sealing member  52   1  can be sufficiently brought into close contact with the side surface  50   1 , which makes it possible to maintain the sufficient sealing performance. 
     The reinforcing member  54   1  is embedded in the cover  47 , and hence bond strength between the reinforcing member  54   1  and the cover  47  can be sufficiently increased. The cover  47  and the reinforcing member  54   1  can be integrated together when the cover  47  is formed. Therefore, when compared with the number of manhours required to attach the reinforcing member  54   1  to the cover  47 , the number of manhours to form the cover  47  integrated with reinforcing member  54   1  can be reduced. 
     The reinforcing member  54   1  integrally includes the cylindrical projections  58   1  for clamping together the cover  47  and the face  34   a  of the base  34 . The reinforcing member  54   1  having high rigidity receives clamping torques of the fastening bolts  61 , which makes it possible to effectively prevent the deformation of the seal groove  48   1 . Hence, the sealing performance of the seal groove  48   1  can be improved to a much greater extent. 
     FIG. 9 shows a brake hydraulic controller according to a second embodiment of the present invention. A grommet  53   2  which is fitted into the notch  47   a  of the cover  47  may be provided separately from the sealing member  52   2 . In this case, a seal groove  65  is formed in the grommet  53   2  to become in line with the seal groove  48   1  of the cover  47  when the grommet  53   2  is fitted to the cover  47 . The sealing member  52   2  is fitted into the seal groove  48   1  of the cover  47  and the seal groove  65  of the grommet  53   2 . 
     FIGS. 10 and 11 show a brake hydraulic controller according to a third embodiment of the present invention. The same reference numerals are used to designate the corresponding elements in the first embodiment. 
     In FIG. 10, a seal groove  48   2  having a substantially U-shaped cross section is formed along the entire circumference of the side of the cover  47 , to be attached to the face  34   a  of the base  34 , that faces the face  34   a  of the base  34 . The seal groove  48   2  is made up of an innermost closed surface  49   2  and a pair of side surfaces  50   2 ,  51   2  connected to both sides of the innermost closed surface  49   2  substantially at right angles. A sealing member  52   2  which is fitted in the seal groove  48   2  is elastically brought into contact with the face  34   a.    
     The seal groove  48   2  includes a recess formed along the outer edge of the side of the cover  47  that faces the face  34   a , and a reinforcing member  54   2  which is embedded in the cover  47  and is made of a rigid material. The reinforcing member  54   2  includes a support plate  55   2  which extends substantially in parallel with the face  34   a  and is embedded in the cover  47 , and a side portion  56   2  which is connected to the outer edge of the support plate  55   2  at substantially right angles. 
     The support plate  55   2  is embedded in the cover  47  to be spaced apart from an innermost closed surface  51   2  formed in the cover  47 . The side portion  56   2  forms the side surface  51   2  of the two side surfaces  50   2 ,  51   2 , and the side portion  56   2  is connected to the support plate  55   2 . 
     In FIG. 11, an extended plate  57   2  integrally extends from the side portion  56   2  of the reinforcing member  54   2  so as to come into contact with the face  34   a  of the base  34 . The portions of the extended plate  57   2  corresponding to the screw holes  60   1  extend to the outside. One end of a cylindrical projection  58   2  is integrally formed in the extended plate  57   1 . The fastening bolt  61  to be screwed into the screw hole  60   1  is inserted into the cylindrical projection  58   2 . The lock head  61   a  of the fastening bolt  61  engages with the other side of the cylindrical projection  58   2 . The cover  47  includes an arm  59   2  which covers the extended plate  57   2  and the cylindrical projection  58   2  in order to make it possible to insert the fastening bolts  61  into the cylindrical projection  58   2  from above as well as to engage the lock head  61   a  of the fastening bolt  61  with the other side of the cylindrical projection  58   2 . 
     Even in the third embodiment, the same effects as those obtained in the first embodiment can be obtained. 
     FIGS. 12 and 13 show a brake hydraulic controller according to a fourth embodiment of the present invention. The same reference numerals are used to designate the corresponding elements in each of the previous embodiments. 
     In FIG. 12, a seal groove  483  having a substantially U-shaped cross section is formed along the entire circumference of the side of the cover  47 , to be attached to the  34   a  of the base  34 , that faces the face  34   a  of the base  34 . The seal groove  48   3  is made up of an innermost closed surface  49   3  and a pair of side surfaces  50   3 ,  51   3  connected to both sides of the innermost closed surface  49   3  substantially at right angles. The sealing member  52   1  (or  52   2 ) which is fitted in the seal groove  48   2  is elastically brought into contact with the face  34   a.    
     The seal groove  48   3  has a substantially U-shaped cross section and includes the pair of side surfaces  50   3 ,  51   3  connected to both sides of the innermost closed surface  49   3 . The seal groove  48   3  is formed from a reinforcing member  54   3  which is embedded in the cover  47  and is made of a rigid material. In short, the reinforcing member  54   2  has a substantially U-shaped cross section and a groove forming portion  66  which is provided substantially at right angles with respect to the reinforcing member  54   2 . The groove forming portion  66  has a substantially U-shaped cross section and has an interior surface made by the combination of the innermost closed surface  49   3  and the pair of side surfaces  50   3 ,  51   3 . 
     In FIG. 13, the extended plate  57   2  integrally extends from the groove forming portion  66  of the reinforcing member  54   3  so as to come into contact with the face  34   a  of the base  34 . The portions of the extended plate  57   2  corresponding to the screw holes  60   1  extend to the outside. One end of the cylindrical projection  58   2  is integrally formed in the extended plate  57   2 . The fastening bolt  61  to be screwed into the screw hole  60 , is inserted into the cylindrical projection  58   2 . The lock head  61   a  of the fastening bolt  61  engages with the other side of the cylindrical projection  58   2 . The cover  47  includes the arm  59   2  which covers the extended plate  57   2  and the cylindrical projection  58   2  in order to make it possible to insert the fastening bolts  61  into the cylindrical projection  58   2  from above as well as to engage the lock head  61   a  of the fastening bolt  61  with the other side of the cylindrical projection  58   2 . 
     Even in the fourth embodiment, it is possible to provide sufficient strength in the seal groove  48   3 . The cover  47  and the reinforcing member  54   3  can be integrated together when the cover  47  is formed, which makes it possible to improve the bond strength between the reinforcing member  54   3  and the cover  47 . Further, the manhours required to assemble he reinforcing member  54   3  and the cover  47  into an integrated unit can be reduced. 
     In the fourth embodiment, the mating plane between the exterior surface of the groove forming portion  66  of the reinforcing member  54   3  and the cover  47  is exposed to the outside and inside of the cover  47  without the presence of the sealing member  52   1  or the sealing member  52   2  between the mating plane and the outside and inside of the cover  47 . In contrast to the fourth embodiment, the mating plane between the reinforcing member  54   1  and the cover  47  directly faces the inside of the cover  47 , but it faces the outside with the sealing member  52   1  interposed between the outside and the mating plane, as described in the first embodiment in FIG.  6 . As a result, water is prevented from entering the mating plane between the reinforcing member  54   1  and the cover  47 . Therefore, the cover  47  of the first embodiment can provide superior sealing performance as compared with the cover  47  of the fourth embodiment. Further, the mating plane between the reinforcing member  54   2  and the cover  47  directly faces the outside of the cover  47 , but it faces the inside of the cover with the sealing member  52   2  interposed between the inside and the mating plane, as described in the second embodiment in FIG.  10 . As a result, even if water enters the mating plane between the reinforcing member  54   2  and the cover  47 , the water will not enter the inside of the cover  47 . Therefore, the cover  47  of the second embodiment can provide superior sealing performance as compared with the cover  47  of the fourth embodiment. 
     Although the illustrative embodiments of the present invention have been described in detail in the above, the present invention is not limited to the above described specific embodiments. Various modifications of the present invention can be construed without departing from the scope and spirit of the invention. 
     For example, at least one of the innermost closed surface and the side surfaces connected to both sides of thereof, which form the seal groove, may be formed from a reinforcing member to be bonded to the cover. Further, only the innermost closed surface of the elements constituting the seal groove, that is, the innermost closed surface and both side surfaces of the seal groove, may be formed from the reinforcing member. 
     As described above, according to the brake hydraulic controller of the first embodiment, a cover is attached to one side of a base so as to cover normally open electromagnetic valves, normally closed electromagnetic valves, reservoirs, and dampers mounted on the same side of the base. A sealing member which comes into elastic contact with the above described side of the base is attached to a seal groove formed in the cover. As a result, the volume of the space formed in the cover is relatively increased, and the smooth actuation of the reservoirs is assured. Therefore, it is possible to render the normally open electromagnetic valves, the normally closed electromagnetic valves, the reservoirs, and the dampers waterproof with the use of the minimum number of parts. A reduction in the number of the components makes it possible to reduce the number of manhours required to assembly the brake hydraulic controller. 
     In addition to the configuration of the brake hydraulic controller of the first embodiment, the cover is made from plastic, and the seal groove is made up of an innermost closed end and a pair of side surfaces connected to both sides thereof substantially at right angles, so as to have a substantially U-shaped cross section, according to the brake hydraulic controller of the second embodiment. A reinforcing member, which is made of a rigid material and forms at least one of the innermost closed surface and the side surfaces, is provided in the cover. As a result, it is possible to firmly maintain the contact between the sealing member and at least one of the innermost closed surface and the side surfaces of the seal groove. Therefore, the cover can provide sufficient sealing performance. 
     In addition to the configuration of the brake hydraulic controller of the second embodiment, the reinforcing member is embedded in the cover, according to the brake hydraulic controller of the third embodiment. Therefore, the bond strength between the reinforcing member and the cover can be increased, and the manhours required to assemble the brake hydraulic controller can be reduced. 
     In addition to the configuration of the brake hydraulic controller of the third embodiment, cylindrical portions having one end brought into contact with the side of the base are integrally formed in the reinforcing member. A lock head of a fastening bolt to be screwed into the base through the cylindrical portion is engaged with the other end of the cylindrical portion. Therefore, the reinforcing member having rigidity receives a clamping torque of the fastening bolt, which in turn prevents the seal groove from being deformed. Hence, the sealing performance of the cover can be improved to a much greater extent.