Patent Publication Number: US-2023137993-A1

Title: Manifold solenoid valve and valve base

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a National Stage application of International Patent Application No. PCT/JP2021/006175, filed on Feb. 18, 2021, which claims priority to Japanese Patent Application No. 2020-041518, filed on Mar. 11, 2020, each of which is hereby incorporated by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The present invention relates to a manifold solenoid valve and a valve base including a solenoid valve aggregate formed by aggregating a plurality of solenoid valves. 
     BACKGROUND 
     A solenoid valve assembly formed by assembling a plurality of solenoid valves is called a solenoid valve manifold or a manifold solenoid valve. As described in Patent Document 1, each solenoid valve includes: a valve housing, that is, a main valve block provided with a spool shaft, i.e., a main valve shaft for switching a flow path; and a solenoid block installed in the main valve block. 
     The solenoid valve manifold includes a split type in which a solenoid valve and a base block mounting the solenoid valve, i.e., a valve base are provided as a solenoid valve unit, the split type being obtained by aggregating the solenoid valve units. Patent Document 2 discloses a split type manifold solenoid valve. The solenoid valve units become an aggregated state and the aggregated state is attached to a support member called a DIN rail, or fastened by a screw member(s). 
     The solenoid valves include types of a single solenoid valve in which one solenoid is incorporated in the solenoid block and a double solenoid valve in which two solenoids are incorporated. The single solenoid valve drives the main valve shaft with one solenoid, and if application of a drive signal to the solenoid is stopped, the main valve shaft returns to an original position by a return force consisting of a spring force or air pressure. Even if the double solenoid valve stops applying the drive signal to one solenoid, the main valve shaft retains its original state until the drive signal is applied to the other solenoid. Patent Document 1 discloses the double solenoid valve. 
     In the manifold solenoid valve, there are two wiring specifications of: a positive common type in which a positive terminal of a coil is set at a common terminal, that is, a common terminal; and a negative common type in which a negative terminal of the coil is set at a common terminal. 
     A cable is connected to a wiring block of the manifold solenoid valve in order to apply the drive signal to each solenoid from an external controller. A board is attached to each valve base, and a printed wiring provided on the board has an output wiring for sending the drive signal to the solenoid and a coupling wiring for sending the drive signal to another adjacent board. 
     When a plug-in connector, that is, a relay connector is attached to the base block and the solenoid valve is attached to the valve base, a pin(s) of a connecting terminal provided on the solenoid valve is inserted into the relay connector. Patent Document 3 discloses a stacking type manifold solenoid valve used by joining a plurality of manifold bases, that is, valve bases. In order to connect a coupling terminal of each coupling wiring to an input terminal of a board provided on another adjacent base block, the adjacent boards are coupled by a connector member, and the coupling wiring of the adjacent board is connected.
     Patent Document 1: Japanese Patent Application Laid-open No. H8-35573   Patent Document 2: Japanese Patent Application Laid-open No. 2010-174964   Patent Document 3: Japanese Patent Application Laid-open No. 2004-36841   

     SUMMARY 
     Problems to be Solved by the Invention 
     In a conventional manner, to assemble a stacking type manifold solenoid valve in which the board provided with the auxiliary connector is attached to the valve base and that electrically connects the relay connector and the auxiliary connector, the board and the auxiliary connector, which are separate parts, are required. Therefore, the number of parts of the manifold solenoid valve leads to increasing. 
     An object of the present invention is to provide a manifold solenoid valve and a valve base that are capable of reducing the number of parts. 
     Means for Solving the Problems 
     A manifold solenoid valve of the present invention having at least one solenoid valve unit that includes a solenoid valve provided with at least one solenoid and a valve base mounting the solenoid valve, the manifold solenoid valve including: a board provided with a plurality of output terminals that are electrically connected to a terminal of the solenoid; a board connector provided on the board and forming a board assembly by a combination with the board; a plurality of input terminals provided on the board assembly at intervals; a plurality of coupling terminals provided on the board assembly at intervals and connected to an input terminal of another adjacent board assembly; an output wiring provided on the board assembly and connecting the output terminals and the input terminals; and a coupling wiring provided on the board assembly and connecting the coupling terminals to the input terminals, wherein a plurality of output pins that are inserted into a pin insertion hole formed in the valve base and that form the output terminals are provided on the board assembly. 
     A valve base of the present invention forming a manifold solenoid valve that solenoid valves each provided with at least one solenoid are mounted on, the solenoid valves being stricken against each other, the valve base including: a valve base main body on which a solenoid valve mounting face, a pin insertion hole, a board installing hole penetrating in a width direction are formed; a board assembly having a board provided with a plurality of output terminals electrically connected to a terminal of the solenoid and a board connector provided on the board, and attached to the board installing hole; a plurality of input terminals provided on the board assembly at intervals; a plurality of coupling terminals provided on the board assembly at intervals and connected to the input terminals provided on another adjacent board assembly; an output wiring provided on the board assembly and connecting the output terminals and the input terminals; and a coupling wiring provided on the board assembly and connecting the coupling terminals to the input terminals, wherein a plurality of output pins inserted into the pin insertion hole and forming the output terminals are provided on the board assembly. 
     Effects of the Invention 
     The board assembly attached to the valve base is formed by the board and the board connector, the board is provided with the plurality of input terminals, the board connector is provided with the plurality of coupling terminals, and the solenoid terminal to which the terminal of the solenoid is coupled via the relay connector is connected to the input terminals by the output wiring. The output terminal is formed by an output pin that is a pin member and, by attaching the board assembly to the valve base, the output pin is inserted into the pin insertion hole of the valve base, and the output pin is electrically connected to the solenoid terminal. Since the output pin supported by the valve base is provided on the board, the valve base can be manufactured with the small number of parts. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a perspective view showing a front side of a manifold solenoid valve according to one embodiment; 
         FIG.  2    is a perspective view showing a back side of  FIG.  1   ; 
         FIG.  3    is an exploded perspective view which looks at a solenoid valve unit from the front side; 
         FIG.  4    is an exploded perspective view which looks at the solenoid valve unit from the back side; 
         FIG.  5    is an enlarged perspective view which looks at a valve base from the front side; 
         FIG.  6    is an enlarged perspective view which looks at the valve base from a bottom side; 
         FIG.  7    is a partially cutaway perspective view showing the valve base in a state where a relay connector is installed; 
         FIGS.  8 (A) and  8 (B)  are both connection diagrams of a plus common type solenoid valve and a board assembly,  FIG.  8 (A)  shows a double solenoid valve, and  FIG.  8 (B)  shows a single solenoid valve; 
         FIGS.  9 (A) and  9 (B)  are both connection diagrams of a minus common type solenoid valve and a board assembly,  FIG.  9 (A)  shows a double solenoid valve, and  FIG.  9 (B)  shows a single solenoid valve; 
         FIGS.  10 (A),  10 (B) and  10 (C)  are views in which  FIG.  10 (A)  is a plan view showing a state where two board assemblies are combined,  FIG.  10 (B)  is a cross-sectional view taken along line  10 B- 10 B in  FIG.  10 (A) , and  FIG.  10 (C)  is a cross-sectional view showing a portion similar to  FIG.  10 (B)  in a state of separating the two board assemblies; 
         FIG.  11    is a back view of  FIG.  10 (A) ; 
         FIGS.  12 (A) and  12 (B)  are both views in which  FIG.  12 (A)  is a side view of the valve base, and  FIG.  12 (B)  is a cross-sectional view taken along line  12 B- 12 B in  FIG.  12 (A) ; and 
         FIG.  13    is a partly-notched perspective view of the valve base in which the valve base is notched at a portion of a board installing hole, and shows a surface to which the board assembly is attached. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. A manifold solenoid valve  10  shown in  FIGS.  1  and  2    has a solenoid valve aggregate  12  formed by aggregating four solenoid valve units  14 , each of which has a valve base  15  mounting a solenoid valve  11 , and is a stacking type. The solenoid valve  11  has a main valve block  13   a  and a solenoid block  13   b  installed on the main valve block  13   a . The solenoid valve aggregate  12  is formed by striking respective valve bases  15  of the solenoid valve units  14  against each other. Incidentally, the number of solenoid valve units  14  constituting the solenoid valve aggregate  12  in  FIGS.  1  and  2    is one example, and the manifold solenoid valve  10  can be assembled by configurating the solenoid valve aggregate  12  with the arbitrary number of solenoid valve units  14 . 
     Piping blocks  16   a ,  16   b  are stricken against both ends of the solenoid valve aggregate  12 , and the solenoid valve aggregate  12  is installed on the piping blocks  16   a ,  16   b . A joint plate  19  provided with a supply port  18  and an exhaust port  17  is attached to each of the piping blocks  16   a ,  16   b . The supply port  18  is connected to an air supply source via a pipe (not shown). Connected to the exhaust port  17  is a unshown discharge pipe or silencer as needed. If the discharge pipe and silencer are unnecessary, nothing may be connected to the exhaust port  17 . A lid member  19   a  having the same shape as the joint plate  19  is detachably attached to surfaces of the piping blocks  16   a ,  16   b , and when the lid member  19   a  and the joint plate  19  are replaced, the supply port  18  and the exhaust port  17  become a form of being installed on the surfaces of the piping block  16   a ,  16   b.    
     As shown in  FIGS.  3  and  4   , the valve base  15  has: a valve base main body  20  shaped into a substantially rectangular parallelepiped shape by a resin; a joint plate  23  installed on the valve base main body  20 ; and a relay connector  41  and a board assembly  42  that are attached to the valve base main body  20 . A solenoid valve mounting face  21  is provided on a surface of the valve base main body  20 , and the solenoid valve  11  is mounted on the solenoid valve mounting face  21 . The joint plate  23  provided with two output ports  22   a ,  22   b  is installed on a front surface of each valve base main body  20 , and the respective output ports  22   a ,  22   b  are connected to a pneumatically operated device by piping. 
     As shown in  FIGS.  3  and  4   , formed in the valve base main body  20  are a supply hole  24  and two exhaust holes  25   a ,  25   b . When the plurality of valve bases  15  are stricken, the plurality of supply holes  24  form a supply passage in a valve base aggregate and the plurality of exhaust holes  25   a  form a first exhaust flow path and the plurality of exhaust holes  25   b  form a second exhaust flow path. The supply passage communicates with the supply port  18 , and each exhaust flow path communicates with the exhaust port  17 . 
     As shown in  FIG.  5   , a supply communication hole  26  that opens on the solenoid valve mounting face  21  is provided in the valve base main body  20 , and the supply communication hole  26  communicates with the supply hole  24 . Two output communication holes  27   a ,  27   b  are provided on both sides of the supply communication hole  26 , the output communication hole  27   a  communicates with the output port  22   a , and the output communication hole  27   b  communicates with the output port  22   b . An exhaust communication hole  28   a  is provided adjacent to the output communication hole  27   a , an exhaust communication holes  28   b  is provided adjacent to the output communication hole  27   b , and the respective exhaust communication holes  28   a ,  28   b  communicate with the exhaust port  17  via the exhaust holes  25   a ,  25   b.    
     The main valve block  13   a  has an input port communicating with the supply communication hole  26 , two output ports communicating with the respective output communication holes  27   a ,  27   b , and two exhaust ports communicating with the exhaust communication holes  28   a ,  28   b . These ports are omitted in the figures. A main valve shaft (not shown) is incorporated in the main valve block  13   a . The main valve shaft switches a flow path at a position of causing the supply communication hole  26  of the valve base  15  to communicate with one output communication hole  27   a  and of supplying compressed air to the output port  22   a  and at a position of causing the supply communication hole  26  to communicate with the other output communication hole  27   b  and of supplying compressed air to the output port  22   b . When the output communication hole  27   a  communicates with the output port  22   a , the output port  22   b  communicates with the exhaust communication hole  28   b . When the output communication hole  27   b  communicates with the output port  22   b , the output port  22   a  communicates with the exhaust communication hole  28   a.    
     Since the manifold solenoid valve  10  includes two piping blocks  16   a ,  16   b , it can supply compressed air from the two supply ports  18  to the supply holes  24 . However, only one of the two piping blocks  16   a ,  16   b  may be provided. The lid member  23   a  having the same shape as the joint plate  23  is detachably attached to a surface of the main valve block  13   a , and when the lid member  23   a  and the joint plate  23  are replaced, the manifold solenoid valve  10  becomes such a form that the output ports  22   a ,  22   b  are installed on the valve block  13   a.    
     At least one solenoid, i.e., a coil is incorporated in the solenoid block  13   b . Pilot air is supplied to a piston provided on the main valve shaft by a drive signal supplied to the solenoid, and the main valve shaft is driven in an axial direction. In this way, the solenoid valve  11  is an indirect actuated type that has a pilot solenoid valve. An exhaust communication hole  31  for pilot air to discharge the pilot air, which is supplied to the piston of the main valve shaft, is provided in the valve base main body  20 , and the exhaust communication hole  31  communicates with a pilot port provided in the main valve block  13   a . When the solenoid valve  11  is an external pilot type, a supply communication hole  32  for pilot air is provided in the valve base  15  in order to supply pilot air to the piston from exteriorly. 
     As shown in  FIGS.  1  and  2   , an end block  33   a  is integrally provided with the piping block  16   a , and an end block  33   b  is integrally provided with the piping block  16   ba . By installing a screw member to an installing hole  34  provided in each of the end blocks  33   a ,  33   b , the manifold solenoid valve  10  can be installed on a support base (not shown). Further, by fixing the end blocks  33   a ,  33   b  to a DIN rail (not shown), the manifold solenoid valve  10  can be installed on the DIN rail. 
     As shown in  FIG.  1   , a power supply block  35  is installed on the end block  33   a . The power supply block  35  includes a connector bracket  36  to which a cable connected to an external controller is connected, and a connector (not shown) provided on the connector bracket  36  is electrically connected to a solenoid incorporated in each solenoid block  13   b . Consequently, the drive signal from the controller is applied to each solenoid, and supply of compressed air to a pneumatically operated device is controlled by a flow path switching movement due to the main valve shaft. 
     As shown in  FIGS.  3  to  5   , a connector accommodating portion  37  is formed so as to open to the solenoid valve mounting face  21  on a back side of the valve base main body  20 . Further, a board installing hole  38  is formed in the valve base main body  20 , and the board installing hole  38  penetrates in a width direction of the valve base main body  20 . When the relay connector  41  is attached into the connector accommodating portion  37  and the solenoid valve  11  is arranged on the solenoid valve mounting face  21  of the valve base  15 , a fitting portion  13   c  provided with a solenoid terminal is fitted to the relay connector  41 . 
     The board assembly  42  is inserted into the board installing hole  38  from its one side and is installed on the valve base main body  20 . The board assembly  42  includes a board  43  and a board connector  44 , and the board assembly  42  is formed by combining the board  43  and the board connector  44 . When the valve base  15  to which the board assembly  42  is attached is stricken against another valve base at their side surfaces, it is attached to a board connector  44  of another adjacent valve base  15 , and an input terminal provided on the board  43  is connected to a coupling terminal of another adjacent board connector  44 . Consequently, the wirings provided in the board assemblies  42  by linking all the board assembles  42  are connected, and the drive signal from the controller is applied to each solenoid. 
     The solenoid valve  11  has specifications of a single solenoid valve incorporating a single solenoid and a double solenoid valve incorporating two solenoids, and the manifold solenoid valve  10  has a form that includes any one of the solenoid valves  11  having a single solenoid valve and a double solenoid valve or a form in which both are mixed. Further, the wiring specification of the manifold solenoid valve  10  includes a positive common type in which a positive side terminal of a solenoid, that is, a coil is a common terminal, and a negative common type in which a negative side terminal thereof is a common terminal. 
       FIG.  8    is a wiring diagram of a solenoid valve and a board assembly when a wiring specification is a plus common type, (A) showing a case where the solenoid valve is a double solenoid valve, and (B) showing a case where the solenoid valve is a single solenoid valve. Meanwhile,  FIG.  9    is a connection diagram of a solenoid valve and a board assembly when a wiring specification is a minus common valve, (A) showing a case where the solenoid valve is a double solenoid valve, and (B) showing a case where the solenoid valve is a double solenoid valve. 
     In  FIGS.  8  and  9   , regarding the solenoid valve  11 , the double solenoid valve is shown by the reference numeral  11   a  and the single solenoid valve is shown by the reference numeral  11   b . Regarding the relay connector  41 , the plus common type is shown by the reference numeral  41   a  (first relay connector), and the minus common type is shown by the reference numeral  41   b  (second relay connector). Further, regarding the board assembly  42 , the board assembly  42  of the double solenoid valve is shown by the reference numeral  42   a , and the board assembly of the single solenoid valve is shown by the reference numeral  42   b . In  FIGS.  8  and  9   , a wiring pattern including the board  43  and the board connector  44  is schematically shown. 
     The double solenoid valve  11   a  has a positive and a negative side solenoid terminal of each of a first solenoid SOL.A and a second solenoid SOL.B, and has a total of four solenoid terminals. The single solenoid valve  11   b  has a positive and a negative side solenoid terminal of the single solenoid SOL.A, and has a total of two solenoid terminals. 
     The relay connectors  41   a ,  41   b  have four solenoid-side connection portions  1  to  4  to which the solenoid terminals are connected. 
     As shown in (A) of  FIG.  8   , the plus common type relay connector  41   a  connected to the double solenoid valve  11   a  has a first board-side connection portion A connected to the solenoid-side connection portion  2 . This board-side connection portion A is electrically connected to one solenoid terminal (minus terminal) of the first solenoid SOL.A via a first internal wiring. The relay connector  41   a  has a second board-side connection portion B connected to the solenoid-side connection portion  4 . This board-side connection portion B is electrically connected to one solenoid terminal (minus terminal) of the second solenoid SOL.B via a second internal wiring. The relay connector  41   a  has a common board-side connection portion COM (common connection portion COM) which is a common connection portion connected to the two solenoid-side connection portions  1 ,  3 . This board-side connection portion COM is electrically connected to the other solenoid terminal (plus side) of each of the first solenoid SOL.A and the second solenoid SOL.B via a third internal wiring. 
     As shown in (B) of  FIG.  8   , when the relay connector  41   a  is connected to the single solenoid valve  11   b , one solenoid terminal (minus side) of the solenoid SOL.A is connected to the solenoid-side connection portion  2  and the board-side connection portion A is electrically connected to one solenoid terminal (minus terminal) of the solenoid SOL.A via the internal wiring. The other solenoid terminal (plus side) of the solenoid SOL.A is connected to the solenoid-side connection portion  1 , and the common board-side connection portion COM is electrically connected to the other solenoid terminal (plus side) of the solenoid SOL.A via the internal wiring. 
     The relay connector  41   a  connected to the single solenoid valve  11   b  does not require the board-side connection portion B and the internal wiring connected to it. Therefore, the relay connector  41   a  connected to the single solenoid valve  11   b  may have or may not have the board-side connection portion B and the internal wiring connected to it. 
     As shown in (A) of  FIG.  9   , the minus common type relay connector  41   b  connected to the double solenoid valve  11   a  has a first board-side connection portion A connected to the solenoid-side connection portion  1 . This board-side connection portion A is electrically connected to one solenoid terminal (plus terminal) of the first solenoid SOL.A via the first internal wiring. The relay connector  41   b  has a second board-side connection portion B connected to the solenoid-side connection portion  3 . This board-side connection portion B is electrically connected to one solenoid terminal (plus terminal) of the second solenoid SOL.B via the second internal wiring. The relay connector  41   b  has a common board-side connection portion COM that is a common connection portion connected to the two solenoid-side connection portions  2 ,  4 . This board-side connection portion COM is electrically connected to the other solenoid terminal (minus side) of each of the first solenoid SOL.A and the second solenoids SOL.B via the third internal wiring. 
     As shown in (B) of  FIG.  9   , when the relay connector  41   b  is connected to the single solenoid valve  11   b , one solenoid terminal (plus side) of the solenoid SOL.A is connected to the solenoid-side connection portion  1  and the board-side connection portion A is electrically connected to one solenoid terminal (plus terminal) of the solenoid SOL.A via the internal wiring. The other solenoid terminal (minus side) of the solenoid SOL.A is connected to the solenoid-side connection portion  2 . The common board-side connection portion COM is electrically connected to the other solenoid terminal (minus side) of the solenoid SOL.A via the internal wiring. 
     The relay connector  41   b  connected to the single solenoid valve  11   b  does not require the board-side connection portion B and the internal wiring connected to it. Therefore, the relay connector  41   b  connected to the single solenoid valve  11   b  may have or may not have the board-side connection portion B and the internal wiring connected to it. 
     As shown in (A) of  FIG.  8    and (A) of  FIG.  9   , the plus common type  41   a  and the minus common type  41   b  of the relay connector  41  are different from each other in an internal wiring structure. By preparing two different types of internal wiring structures, resin parts of both relay connectors  41   a ,  41   b  are shared, and the both relay connectors  41   a ,  41   b  can be manufactured by using one type of resin molding die. 
     As shown in (B) of  FIG.  8    and (B) of  FIG.  9   , the board assembly  42   a  with the double wiring of the double solenoid valve  11   a : has a first output terminal SOLa connected to the first board-side connection portions A of the relay connectors  41   a ,  41   b ; a second output terminal SOLb connected to the second board-side connection portions B; and a third output terminal SOLc which is a common output terminal connected to the common board-side connection portion COM. These output terminals are provided at an end(s) of the board assembly  42   a.    
     As shown in  FIGS.  8 (B) and  9 (B) , the board assembly  42   b  with the single wiring of the single solenoid valve  11   b  has: a first output terminal SOLa connected to the first board-side connection portions A of the relay connectors  41   a ,  41   b ; and a second output terminal SOLc which is a common output terminal connected to the common board-side connection portion COM. These output terminals are provided at an end(s) of the board assembly  42   b.    
     A large number of input terminals IN 1  to INn are provided linearly on the board  43  at regular intervals, and a common coupling terminal INc is provided on the board  43  adjacent to an n-th input terminal INn. The number n of input terminals is set according to the maximum number of solenoid valves  11  constituting one set of manifold solenoid valves  10 . One side of each of the board assemblies  42   a ,  42   b  is a board connector  44 . A large number of coupling terminals OUT 1  to OUTn are provided linearly on the board connector  44  at regular intervals, and the common coupling terminal OUTc is provided on the board connector  44  adjacent to an n-th coupling terminal OUTn. The number n of coupling terminals is the same as the number of input terminals. 
     In the board assembly  42   a  of the double solenoid valve  11   a , the first output terminal SOLa is connected to the first input terminal IN 1  by an output wiring  46   a , and the input terminal IN 1  is connected to the first board-side connection portion A. The second output terminal SOLb is connected to the second input terminal IN 2  by an output wiring  46   b , and the input terminal IN 2  is connected to the second board-side connection portion B. The common output terminal SOLc is connected to the common input terminal INc and the common coupling terminal OUTc by a common coupling wiring  46   c  having a broken line. The first to n-2nd coupling terminals OUT 1  to OUTn- 2  are connected to the third and subsequent input terminals IN 3  to INn by a coupling wiring  46   d , respectively. 
     Meanwhile, in the board assembly  42   b  of the single solenoid valve lib, the first output terminal SOLa is connected to the first input terminal IN 1  by the output wiring  46   a , and the input terminal IN 1  is connected to the first board-side connection portion A. The common output terminal SOLc is connected to the common input terminal INc and the common coupling terminal OUTc by the common coupling wiring  46   c  having a broken line. The first to n-lth coupling terminals OUT 1  to OUTn- 1  are connected to the second and subsequent input terminals IN 2  to INn by a coupling wiring  46   d , respectively. The coupling terminals of the respective board assemblies  42   a ,  42   b  come into contact with the input terminal of another adjacent board assembly. In this way, the board assembly  42   a  and the board assembly  42   b  have different wiring patterns. 
     As shown in  FIG.  5   , the relay connector  41  has a connector main body  51  provided with solenoid-side connection portions  1  to  4  to which the solenoid terminals are connected. The board-side connection portions A, B, COM are provided on a base portion  52  of the connector main body  51  so as to be located on opposite sides of the solenoid-side connection portions  1  to  4 . The base  52  of the relay connector  41  is installed to the installing hole  53  provided in the valve base main body  20 . 
     As shown in  FIGS.  5  and  7   , an end wall portion  54  is provided on a back surface side of the valve base main body  20 . A through hole  55  is formed in the end wall portion  54 , and the through hole  55  penetrates the end wall portion  54  and causes the connector accommodating portion  37  to communicate with an outside of the valve base main body  20 . An engaging recess  56  is formed in the valve base main body  20  so as to oppose the through hole  55 . The relay connector  41  has an exposed claw  57  inserted into the through hole  55 , and an engaging claw  58  engaged with the engaging recess  56 . Therefore, when the relay connector  41  is inserted into the connector accommodating portion  37  and the base portion  52  is installed on the installing hole  53 , the exposed claw  57  enters the through hole  55  and the engaged claw  58  is engaged with the engaging recess  56 . Consequently, the relay connector  41  is prevented from coming off from the connector accommodating portion  37 , and the exposed claw  57 , which is a part of the relay connector  41 , is exposed exteriorly from the through hole  55 . 
     As described above, the specification of the solenoid valve  11  constituting the manifold solenoid valve  10  include the double solenoid valve  11   a  and the single solenoid valve  11   b , and the wiring specification of the manifold solenoid valve  10  includes the plus common type and the minus common type. Besides those, the solenoid valve and the manifold solenoid valve also have other specifications such as waterproof and explosion-proof. A shape of the relay connector  41  may differ depending on the specifications. By making at least a shape, a pattern, and color of a portion exposed from the through hole  55  of the relay connector  41  different according to the specifications, the specifications of the solenoid valve  11  and the manifold solenoid valve  10  can be confirmed. 
     The relay connector  41  includes a plus common type relay connector  41   a  and a minus common type relay connector  41   b . The board assembly  42  includes a double-wiring board assembly  42   a  and a single-wiring board assembly  42   b . By combining any of the two types of relay connectors  41   a ,  41   b  and any of the two types of board assemblies  42   a ,  42   b , the valve base  15  is set to, as shown in Table 1, any one of the four specifications of the plus common type double solenoid valve, the plus common type single solenoid valve, the minus common type double solenoid valve, and the minus common type single solenoid valve. 
     
       
         
           
               
               
               
             
               
                   
                 TABLE 1 
               
               
                   
                   
               
               
                   
                 PLUS COMMON TYPE 
                 MINUS COMMON TYPE 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
            
               
                 SOLENOID 
                 DOUBLE SOLENOID 
                 SINGLE SOLENOID 
                 DOUBLE SOLENOID 
                 SINGLE SOLENOID 
               
               
                 VALVE 11 
                 VALVE 11a 
                 VALVE 11b 
                 VALVE 11a 
                 VALVE 11b 
               
            
           
           
               
               
               
            
               
                 RELAY 
                 PLUS COMMON RELAY 
                 MINUS COMMON RELAY 
               
               
                 CONNECTOR 41 
                 CONNECTOR 41a 
                 CONNECTOR 41b 
               
               
                   
                 (FIRST RELAY CONNECTOR) 
                 (SECOND RELAY CONNECTOR) 
               
            
           
           
               
               
               
               
               
            
               
                   
                 GREEN 
                 BLUE 
                 GRAY 
                 PINK 
               
               
                 BOARD 
                 DOUBLE-WIRING 
                 SINGLE-WIRING 
                 DOUBLE-WIRING 
                 SINGLE-WIRING 
               
               
                 ASSEMBLY 42 
                 BOARD ASSEMBLY 42a 
                 BOARD ASSEMBLY 42b 
                 BOARD ASSEMBLY 42a 
                 BOARD ASSEMBLY 42b 
               
               
                   
               
            
           
         
       
     
     As described above, in order to exteriorly indicate which of the four specifications the solenoid valve  11  constituting the manifold solenoid valve  10  is, the plus common type relay connector  41   a  connected to the double-wiring board assembly  42   a  is colored green, and the plus common type relay connector  41   a  connected to the single-wiring board assembly  42   b  is colored blue. Further, the minus common type relay connector  41   b  connected to the double-wiring board assembly  42   a  is colored gray, and the minus common type relay connector  41   b  connected to the single-wiring board assembly  42   b  is colored pink. 
     The relay connectors  41 , which have been color-coded into the four specifications, are colored by pigments contained in resin materials when each of the relay connectors  41  is resin-molded. As described above, by sharing the resin parts of both the relay connectors  41   a ,  41   b , both the relay connectors  41   a ,  41   b  can be manufactured from the relay connectors  41  indicating the four specifications by using one type of resin molding dies, so that manufacturing efficiency of the relay connector can be improved. 
     In addition to this, since the specifications of the valve base  15  are displayed by the relay connector  41 , it is not necessary to provide the symbol and character, etc. indicating the mold according to each specification on the valve base and to manufacture the valve base with one type of molding dies. Consequently, the manufacturing efficiency of the valve base is improved, and the assembly efficiency of the manifold solenoid valve  10  is improved. The specifications displayed by the relay connector  41  are not limited to the number of solenoids of the solenoid valve  11  and the wiring specifications of the manifold solenoid valve  10 . For example, specifications such as a shape, a function, performance, using parts, and corresponding standards of the manifold solenoid valve  10  or the mountable solenoid valve  11  may be displayed. 
     Since the exposed claw  57 , which is a portion exposed to the through hole  55 , is visually recognized from exteriorly via the through hole  55 , the specifications of the solenoid valve  11  and the wiring specifications of the manifold solenoid valve  10  are can be identified from exteriorly according to the color of the exposed claw  57 . Further, in assembling the manifold solenoid valve  10 , the type of the relay connector  41  to be assembled to the valve base  15  needs to be distinguished according to the type of the solenoid valve  11 , but the type can be distinguished by the color and the assembly efficiency can be improved. 
     As shown in  FIG.  5   , the exposed claw  57  is one, and the engaging claw  58  is formed by two parts each having a width dimension smaller than that of the exposed claw  57 . Further, since the width dimension of the engaging claw  58  is smaller than that of the through hole  55 , the engaging claw  58  is not engaged with the through hole  55 . In this way, by making the exposed claws  57  and the engaging claws  58  mutually different in shape, the relay connector  41  is prevented from being erroneously assembled to the valve base  15  in assembling the relay connector  41  to the valve base  15 , and the assembling workability is improved. 
     As shown in  FIGS.  4  and  5   , the through hole  55  has an outer engaging face  55   a  engaged with a tip surface of the exposed claw  57 , and the engaging recess  56  has an inner engaging face  56   a  engaged with the tip surface of the engaging claw  58 . As shown in  FIG.  5   , a length L 1  from a face of the valve base main body  20 , on which the base portion  52  of the relay connector  41  abuts, to the outer engaging face  55   a  is set to be smaller than a length L 2  to the inner engaging face  56   a . In this way, since engaging positions of the relay connector  41  engaged with the outer engaging face  55   a  and the inner engaging face  56   a  are different, erroneous assembly of the relay connector  41  to the valve base  15  is prevented. 
     As shown in  FIGS.  5  and  6   , one side surface of the valve base  15  is a board insertion face  15   a , and the board assembly  42  is inserted into the board installing hole  38  from a board insertion face  15   a  side. A plurality of input terminals are linearly arranged on the side surface of the board  43  at regular intervals, and the input terminals are provided on both of front and back surfaces of the board  43 . In  FIGS.  5  and  6   , one of the plurality of input terminals provided on both surfaces of the board  43  is denoted by the reference numeral IN. 
     The board connector  44  installed on the other side surface side of the board  43  has a slit  60  into which a board  43  of another adjacent board assembly  42  is inserted, and coupling terminals are linearly arranged on an inner surface of the slit  60  at regular intervals. In  FIGS.  5  and  6   , one of a plurality of input terminals provided on the inner surface of the slit  60  is denoted by the reference number OUT. When the board  43  of the other board assembly  42  is inserted into the board connector  44  of one board assembly  42 , each input terminal IN provided on the board  43  of the other board assembly  42  is connected to each coupling terminal OUT of one board assembly  42 . 
     (A) of  FIG.  10    is a plan view showing a state in which the two board assemblies  42  are combined. The one board connector  44  is upward and downward provided with a plurality of coupling terminals OUT so as to be exposed to the slit  60 , and the input terminals IN connected to the coupling terminals OUT by a coupling wiring  46   d  are provided on both front and back surfaces of the board  43 . Therefore, when the board  43  of the other board assembly  42  is inserted into the slit  60  of the board connector  44  of the one board assembly  42 , the coupling terminal OUT is connected to the input terminal IN. 
     Incidentally, the input terminal IN and the common input terminal INc may be provided on the board connector  44 , and the coupling terminal OUT and the common coupling terminal OUTc may be provided on the board  43 . 
     The first output terminal SOLa, the second output terminal SOLb, and the third output terminal SOLc as described above are provided at the end portion of the board  43 . As shown in  FIG.  11   , a first output pin  61 , a second output pin  62 , and a third output pin  63  connected to conductors serving as output terminals are installed on the back surface side of the board  43 . Each of the output pins  61  to  63  has an L-shape, which protrudes from the back surface of the board  43  and has insertion portions  61   a  to  63   a  extending in parallel with the board  43  in a width direction of the board assembly  42 , thereby constituting an output terminal. 
     As shown in  FIGS.  5  and  6   , a pin support portion  64  is provided on the valve base main body  20 , and the pin support portion  64  is provided with three pin insertion holes  65  correspondingly to the three output pins  61  to  63 . Therefore, when the board assembly  42  is attached to the board installing hole  38 , the respective output pins  61  to  63  are inserted into the pin insertion holes  65 . 
       FIG.  7    shows one side surface  15   b  of the valve base  15 , and this side surface  15   b  is a surface opposite to the board insertion face  15   a . In each pin insertion portion  65 , one end portion of a lead wire  66  is attached to each pin insertion hole  65  from a surface opposite to the pin insertion hole  65 , and the other end portion of the lead wire  66  is attached to the board-side connection portion of the relay connector  41 . Consequently, the output pin  61  as the first output terminal is connected to the first board-side connection portion A of the relay connector  41 , and the output pin  62  as the second output terminal is connected to the second board-side connection portion B, and the output pin  63  as the third output terminal is connected to the third board-side connector portion COM. 
     The board assembly  42   b  of the single solenoid valve  11   b  may have a form of being not provided with the output pin  62 , or may be provided with the output pin  62  as a dummy. 
     (A) of  FIG.  12    shows a side surface  15   b  of the valve base  15 , and (B) of  FIG.  12    is a cross-sectional view taken along line  12 B- 12 B in (A) of  FIG.  12   . When the board assembly  42  is attached to the board installing hole  38 , as shown in (B) of  FIG.  12   , a portion of the coupling terminal provided on the side surface side of the board  43  protrudes from a side surface  15   b  of the valve base  15 . A side surface of the board connector  44  becomes substantially flush with the board insertion surface  15   a  of the valve base  15  and is exposed exteriorly. When the valve bases  15  to be respectively attached to the board assemblies  42  are abutted against each other on their side surfaces, the board  43  of the other board assembly is inserted into the slit  60  of the one board connector  44 . 
     As shown in  FIGS.  5  and  13   , a plurality of engaging protrusions  72   a  to  72   c  are provided on the surface of the board connector  44 . The engaging protrusions  72   a  and  72   c  have line-symmetrical L-shapes, and the engaging protrusion  72   b  has a T-shape. As shown in  FIG.  6   , the back surface of the board connector  44  is also provided with engaging projections  72   a  to  72   c . When the board assembly  42  is attached to the board installing hole  38 , the engaging claws  73  engaged with the engaging protrusions  72   a ,  72   c  are provided on the valve base main body  20  as shown in  FIG.  5   . By engaging the engaging claws  73  with the engaging projections  72   a ,  72   c , the board assembly  42  is positioned at and fixed to a predetermined position on the valve base main body  20 . 
     As shown in  FIGS.  11  and  13   , a board connector support face  71  is provided on the valve base  15 , and a base contact face  76  is provided on each of the engaging projections  72   a  to  72   c . When the board assembly  42  is attached to board installing hole  38 , the base contact surface  76  abuts against and is supported by the board connector support face  71 , and the board assembly  42  is positioned at a predetermined position of the valve base main body  20 . In this way, the board connector  44  supports the board assembly  42  by abutting against the valve base  15 . 
     As shown in  FIG.  13   , a plurality of protrusion portions  74   a ,  74   b  project from the side surface  15   b  and are provided on the valve base main body  20 . The protrusion portion  74   a  is a quadrangular protrusion, and the protrusion portion  74   b  is an L-shaped protrusion. Recesses  75 , into which the protrusion portions  74  of the adjacent board assembly  42  are inserted correspondingly to the respective protrusion portions  74   a ,  74   b , are opened to the board insertion face  15   a  and are provided in the valve base main body  20 . Further, a shape of the protrusion portion  74   b  is a shape corresponding to the engaging protrusion  72   b , and is inserted between the engaging protrusion  72   b  and the engaging claw  73 . Consequently, when the side surfaces are brought into contact with each other and the plurality of valve bases  15  are abutted against each other, the adjacent valve bases  15  becomes a state where the protrusion portions  74  are meshed with each other and the adjacent valve bases  15  are combined with each other in a predetermined positional relationship. 
     The present invention is not limited to the above-described embodiments, and can be variously modified within a range not departing from the scope thereof. The solenoid valve  11  may be not an indirectly actuated type in which pilot air is controlled by the pilot solenoid valve to drive the main valve shaft but a directly actuated type in which the valve body is directly driven by the solenoid. A stop valve for stopping the supply of air to each of the solenoid valves  11 , an air supply block for supplying air directly to each of the solenoid valves  11 , an exhaust block for exhausting air from each of the solenoid valves  11 , or the like may be provided between the solenoid valve  11  and the valve base  15 , and the solenoid valves  11  may be mounted on the valve bases  15  without abutting against the valve base  15 . Further, a block plate for sealing the supply communication holes  26 , the output communication holes  27   a ,  27   b , and the exhaust communication holes  28   a ,  28   b  may be mounted on the valve base  15  without mounting the solenoid valve  11  on the valve base  15 . 
     INDUSTRIAL APPLICABILITY 
     The manifold solenoid valve has the valve bases and is used in a technical field of using the pneumatically actuated device in order to control the supply of compressed air to the pneumatically actuated device. 
     While the present disclosure has been illustrated and described with respect to a particular embodiment thereof, it should be appreciated by those of ordinary skill in the art that various modifications to this disclosure may be made without departing from the spirit and scope of the present disclosure.