Patent Publication Number: US-8523246-B2

Title: Connector

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is entitled to the benefit of and incorporates by reference essential subject matter disclosed in International Patent Application No. PCT/JP2009/052060 filed on Feb. 6, 2009 and Japanese Patent Application No. JP2008-066220 filed Mar. 14, 2008. 
     TECHNICAL FIELD 
     The present invention relates to a connector which detachably couples fluid apparatuses such as a filter, a regulator, and a lubricator with each other in an air-tight manner. 
     BACKGROUND ART 
     Compressed air is supplied from an air pressure source to a pneumatic actuator via a pneumatic circuit, the pneumatic actuator converting fluid energy to mechanical energy like a pneumatic cylinder or the like. The pneumatic circuit is provided with a filter for removing dusts or moisture in the compressed air supplied from the air pressure source, an also provided with a regulator for adjusting pressure of the compressed air supplied to the pneumatic actuator. Further, when the compressed air is supplied to the pneumatic actuator after a mist lubricant is injected into the compressed air, a lubricator is provided in the pneumatic circuit. 
     Fluid apparatuses such as a filter and a regulator are mutually coupled detachably to be utilized as an air treatment unit in order to facilitate maintenance and inspection of the fluid apparatuses and they are provided in the pneumatic circuit. A connector is used for mutually coupling the fluid apparatuses detachably in an air-tight manner. The connector includes a member which has a through-hole and seal faces and is disposed between fluid ports of respective fluid apparatuses and a member which mutually fastens fluid apparatuses adjacent to each other, and the fluid apparatuses are joined to each other by the connector in an air-tight manner and are caused to communicate with each other through the through-hole. Such connectors are described in Patent Documents 1 to 3, for example.
     Patent Document 1: Japanese Patent Application Laid-Open Publication (Translation of PCT Application) No. 09-501756   Patent Document 2: Japanese Patent No. 2715049   Patent Document 3: Japanese Patent No. 2902389   

     DISCLOSURE OF THE INVENTION 
     Problems to be Solved by the Invention 
     The filter includes a coupling head provided with a fluid port on an inflow side and a fluid port on an outflow side, and a bowl assembled to the coupling head for receiving water droplets or dusts removed from air, and the bowl is attached to the pneumatic circuit such that the bowl is positioned below the coupling head. The lubricator is also attached to the pneumatic circuit such that a bowl receiving lubricant is positioned on a lower side. When the filter or the lubricator is installed, it is necessary to ensure a vertical directionality thereof in this manner, and when a regulator is coupled to a filter, the regulator is coupled to the filter such that a valve assembly is positioned below the coupling head while correspondence to the filter is maintained. Accordingly, the air treatment unit is assembled such that respective functional parts of the fluid apparatuses are positioned on a lower side. 
     However, when another apparatus is arranged around the air treatment unit, such a case occurs that the functional parts of the fluid apparatus interfere with the other apparatus so that many apparatuses cannot be arranged in a limited space. The filter or the regulator must be arranged such that the bowl which is the functional part is positioned on the lower side, and so has directionality, but the regulator does not have directionality, where the regular can perform its function even when the valve assembly which is the functional part is positioned above the coupling head or it is oriented in a horizontal direction. Similarly, a residual pressure exhaust valve does not have vertical directionality. 
     If a fluid apparatus which does not have directionality can be coupled to a fluid apparatus having directionality at any of a plurality of postures, another apparatus can be arranged in a limited space. 
     A preferred aim of the present invention is to provide a connector which can couple a fluid apparatus which does not have directionality to a fluid apparatus which has directionality at an arbitrary posture. 
     Means for Solving the Problems 
     A connector of the present invention is a connector connecting two fluid apparatuses of the same type or different types selected from: a first fluid apparatus in which a flange having a butting face at which a fluid port is opened is provided on a coupling head, the first fluid apparatus having clamp portions to which clamp grooves are formed on two sides of the flange parallel with each other between the clamp portions and the coupling head; and a second fluid apparatus in which a flange having a butting face at which a fluid port is opened is provided on a coupling head, the second fluid apparatus having clamp portions to which clamp grooves are formed on four sides of the flange between the clamp portions and the coupling head, the connector including: a coupling block provided with: a spacer portion having seal faces contacting the butting faces of the two fluid apparatuses and formed on both faces of the spacer portion and having a through-hole causing the fluid ports of the two fluid apparatuses to communicate with each other; and an operating portion provided on one side of the spacer portion; tongue portions provided on the operating portion corresponding to both the faces of the spacer portion and formed with wedge faces contacting wedge faces of the clamp portions of the two fluid apparatuses; a seal member attached between the butting face and the seal face so as to surround the through-hole; a fastening member provided with tongue portions opposed to the tongue portions of the operating portion and contacting the wedge faces of the clamp portions, the fastening member being detachably fastened to the other side of the coupling block; and guide protrusions provided on end of the operating portion, the guide protrusions being inserted into recessed guide portions formed on two sides of the flange when the coupling block is attached to the flange of the first fluid apparatus by inserting the tongue portions into one of the clamp grooves on the two sides, and the guide protrusions being capable of being inserted into any of recessed guide portions formed on the four sides of the flange, respectively, when the coupling block being attached to the flange of the second fluid apparatus by inserting the tongue portions into any of the clamp grooves on the four sides, wherein the second fluid apparatus can be coupled to the first fluid apparatus that has a vertical directionality in any direction of vertical and horizontal directions. 
     The connector of the present invention is the connector in which the recessed guide portions are formed between guide portions, which are provided on the other two sides of the flange of the first fluid apparatus, and the coupling head; the guide protrusions are inserted into the recessed guide portions formed on the other two sides of the flange when the coupling block is attached to the flange of the first fluid apparatus; and the clamp grooves on the four sides form the recessed guide portions into which the guide protrusions are inserted when the coupling block is attached to the flange of the second fluid apparatus. 
     The connector of the present invention is the connector in which a first guide protrusion provided on one end of the operating portion has a shape corresponding to one of the recessed guide portions on the two sides of the first fluid apparatus, and a second guide protrusion provided on the other end of the operating portion has a shape corresponding to the other one of the recessed guide portions on the two sides of the first fluid apparatus. 
     The connector of the present invention is the connector in which the one of the recessed guide portions and the other one of the recessed guide portions are different in length dimension from each other, and the first guide protrusion has a length corresponding to the one of the recessed guide portions, while the second guide protrusion has a length corresponding to the other one of the recessed guide portions. 
     The connector of the present invention is the connector in which the one of the recessed guide portions and the other one of the recessed guide portions are different in width dimension from each other, and the first guide protrusion has a width corresponding to the one of the recessed guide portions, while the second guide protrusion has a width corresponding to the other one of the recessed guide portions. 
     The connector of the present invention is the connector in which a third guide protrusion projecting toward the first guide protrusion and having a shape corresponding to the first guide protrusion is provided on one end of the fastening member, and a fourth guide protrusion projecting toward the second guide protrusion and having a shape corresponding to the second guide protrusion is provided on the other end of the fastening member. 
     The connector of the present invention is the connector in which a clamp groove is formed to an entire peripheral portion of the clamp portion of the second fluid apparatus, and the guide protrusions are inserted into any of the clamp grooves on the four sides when the coupling block is attached to the flange of the second fluid apparatus. 
     The connector of the present invention is the connector in which the recessed guide portions are formed on the two sides of the flange of the first fluid apparatus; the recessed guide portions are formed on the four sides of the flange of the second fluid apparatus; and the guide protrusions are inserted into the recessed guide portions formed on the two sides of the flange when the coupling block is attached to the flange of the first fluid apparatus, while the guide protrusions are inserted into any of the recessed guide portions on the four sides when the coupling block is attached to the flange of the second fluid apparatus. 
     The connector of the present invention is the connector in which a first guide protrusion provided on one end of the operating portion has a shape corresponding to one of the two recessed guide portions formed on the two sides of the first fluid apparatus, respectively, and a second guide protrusion provided on the other end of the operating portion has a shape corresponding to the other one of the two recessed guide portions formed on two sides of the first fluid apparatus, respectively. 
     The connector of the present invention is the connector in which the one of the recessed guide portions and the other one of the recessed guide portions are different in length dimension from each other, and the first guide protrusion has a length corresponding to the one of the recessed guide portions, while the second guide protrusion has a length corresponding to the other one of the recessed guide portions. 
     The connector of the present invention is the connector in which the one of the recessed guide portions and the other one of the recessed guide portions are different in sectional shape from each other, and the first guide portion has a sectional shape corresponding to the one of the recessed guide portions, while the second guide protrusion has a sectional shape corresponding to the other one of the recessed guide portions. 
     The connector of the present invention is the connector in which a third guide protrusion projecting toward the first guide protrusion and having a shape corresponding to the first guide protrusion is provided on one end of the fastening member, and a fourth guide protrusion projecting toward the second guide protrusion and having a shape corresponding to the second guide protrusion is provided on the other end of the fastening member. 
     Effects of the Invention 
     According to the present invention, the flange of the first fluid apparatus having the vertical directionality is provided with guide grooves on its two sides, and the guide grooves on the two sides are different in shape from each other. The flange of the second fluid apparatus having no vertical directionality is provided with clamp grooves on its four sides. The connector which connects two fluid apparatuses to each other has guide protrusions inserted into one of the guide grooves of the flange having two sides of the first fluid apparatus and inserted into any of the clamp grooves on the four sides of the second fluid apparatus. Thereby, the second fluid apparatus having no vertical directionality can be coupled to another fluid apparatus with an upright or downward posture or with a leftward or rightward posture. 
     Accordingly, when the second fluid apparatus is coupled to the first fluid apparatus adjacent thereto, a surrounding space which should be provided around the first fluid apparatus can be effectively utilized by setting the posture of the second fluid apparatus according to the surrounding space to arrange another apparatus in the surrounding space. 
     According to the present invention, not only that the first fluid apparatus and the second fluid apparatus can be coupled to each other but also that two first fluid apparatuses or two second fluid apparatuses can be coupled mutually. Respective fluid apparatuses can be coupled in any order. 
    
    
     
       BRIEF DESCRIPTIONS OF THE DRAWINGS 
         FIG. 1  is a perspective view illustrating an air treatment unit attached with a connector according to an embodiment of the present invention; 
         FIG. 2  is an exploded perspective view illustrating a filter, a regulator, and the connector illustrated in  FIG. 1 ; 
         FIG. 3  is a sectional view of the air treatment unit taken along the line  3 - 3  in  FIG. 1 ; 
         FIG. 4  is a sectional view of the air treatment unit taken along the line  4 - 4  in  FIG. 1 ; 
         FIG. 5  is a side view of the filter viewed from a direction of the arrow  5  in  FIG. 2 ; 
         FIG. 6  is a side view of the regulator viewed from a direction of the arrow  6  in  FIG. 2 ; 
         FIG. 7  is a side view of the connector viewed from a direction of the arrow  7  in  FIG. 2 ; 
         FIG. 8A  is a sectional view of the air treatment unit taken along the line  8 A- 8 A in  FIG. 1 ; 
         FIG. 8B  is a sectional view of the air treatment unit taken along the line  8 B- 8 B in  FIG. 1 ; 
         FIG. 9  is a sectional view illustrating a state that a coupling block and a fastening member are vertically inverted with respect to a filter; 
         FIG. 10  is a perspective view showing a modified embodiment of the air treatment unit; 
         FIG. 11  is an exploded perspective view illustrating a connector according to another embodiment; 
         FIGS. 12A and 12B  are a side view of a filter viewed from a direction of the arrow  12 A in  FIG. 11  and a front view of the filter viewed from a direction of the arrow  12 B in  FIG. 11 , respectively; 
         FIGS. 13A and 13B  are a side view of a coupling block viewed from a direction of the arrow  13 A in  FIG. 11  and a front view of the coupling block viewed from a direction of the arrow  13 B in  FIG. 11 ; 
         FIG. 14  is a front view illustrating a state that a coupling block illustrated in  FIG. 11  is vertically inverted with respect to a filter; 
         FIG. 15  is an exploded perspective view illustrating a connector according to another embodiment; 
         FIGS. 16A and 16B  are a front view and a side view of a filter, respectively; 
         FIGS. 17A and 17A  are a front view and a side view of a regulator, respectively; 
         FIG. 18A  is a side view of a coupling block and a fastening member; 
         FIG. 18B  is a front view of the coupling block; 
         FIGS. 19A and 19B  are a front view and a side view of a filter, respectively; 
         FIGS. 20A and 20B  are a front view and a side view of a regulator, respectively; 
         FIG. 21A  is a side view of a coupling block and a fastening member; 
         FIG. 21B  is a front view of the coupling block; 
         FIGS. 22A and 22B  are a front view and a side view of a filter, respectively; 
         FIGS. 23A and 23B  are a front view and a side view of a regulator, respectively; 
         FIG. 24A  is a side view of a coupling block and a fastening member; 
         FIG. 24B  is a front view of the coupling block; 
         FIGS. 25A and 25B  are a front view and a side view of a filter, respectively; 
         FIGS. 26A and 26B  are a front view and a side view of a regulator, respectively; 
         FIG. 27A  is a side view of a coupling block and a fastening member; and 
         FIG. 27B  is a front view of the coupling block. 
     
    
    
     BEST MODE FOR CARRYING OUT THE INVENTION 
     Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 
     An air treatment unit illustrated in  FIG. 1  includes three fluid apparatuses of a filter  10 , a regulator  11 , and a lubricator  12 . Compressed air supplied from an air pressure source flows into the filter  10 , so that moisture contained in the compressed air as fine water droplets is removed by a centrifugal separation action and a filtering action possessed by the filter  10 . The compressed air which has flowed into the regulator  11  serving as a pressure-reducing valve from the filter  10  is reduced to a predetermined pressure lower than a pressure on an inlet side and guided into the lubricator  12 . In the lubricator  12 , lubricant is turned into a mist and mixed into the compressed air according to an air flow rate, and the lubricant is supplied to a movable portion of a pneumatic actuator. 
     The filter  10  has a substantially-cubic coupling head  14  connected to the regulator  11  by the connector  13 , and a bowl  15  is attached to a lower side of the coupling head  14  and a filter element (not illustrated) is also attached thereto. Moisture in the compressed air which has flowed in the filter  10  is accumulated in the bowl  15  and foreign matter therein is removed by the filter element. A bowl guard  15   a  is attached to an outside of the bowl  15  so as to cover the bowl  15 . The lubricator  12  similarly includes a substantially-cubic coupling head  16 , and a bowl  17  receiving a lubricant is attached to a lower side of the coupling head  16 , and the lubricant is turned into a mist and supplied to the compressed air. A bowl guard  17   a  is attached to an outside of the bowl  17  so as to cover the bowl  17 . The filter  10  and the lubricator  12  must be arranged such that the respective bowls  15  and  17  are positioned on lower sides of the filter  10  and the lubricator  12  and they configure first fluid apparatuses having a vertical directionality. 
     On the other hand, the regulator  11  has a substantially-cubic coupling head  18 , and a valve mechanism which adjusts pressure of the compressed air which has passed through the filter  10  to be purified is assembled in the coupling head  18 . The coupling head  18  is provided with a handle  19  extending downward in  FIG. 1 , so that the set pressure for a pressure on the outlet side is adjusted by the handle  19 . The regulator  11  may be arranged such that the handle  19  is positioned on an upper side of the regulator  11  or oriented in a horizontal direction, and the regulator  11  has any directionality of vertical and horizontal directions to configure a second fluid apparatus having no directionality. 
     The filter  10  and the regulator  11  are detachably coupled to each other at their coupling heads  14  and  18  in an air-tight manner by a connector  13 , and the regulator  11  and the lubricator  12  are similarly coupled to each other by another connector  13 . 
       FIG. 2  is an exploded perspective view illustrating the filter, the regulator, the connector illustrated in  FIG. 1 , and  FIG. 3  is a sectional view of the air treatment unit taken along the line  3 - 3  in  FIG. 1 ,  FIG. 4  is a sectional view of the air treatment unit taken along the line  4 - 4  in  FIG. 1 ,  FIG. 5  is a side view of the filter viewed from a direction of the arrow  5  in  FIG. 2 ,  FIG. 6  is a side view of the regulator viewed from a direction of the arrow  6  in  FIG. 2 ,  FIG. 7  is a side view of the connector viewed from a direction of the arrow  7  in  FIG. 2 ,  FIG. 8A  is a sectional view of the air treatment unit taken along the line  8 A- 8 A in  FIG. 1 , and  FIG. 8B  is a sectional view of the air treatment unit taken along the line  8 B- 8 B in  FIG. 1 . 
     Flanges  21  and  22  each having a butting face  20  are provided on two side faces of the coupling head  14  of the filter  10  positioned on opposite sides of the coupling head  14 , respectively. As illustrated in  FIG. 1  and  FIG. 2 , a fluid port  23   a  on an inflow side is opened on the butting face  20  of one flange  21 , while a fluid port  23   b  on an outflow side is opened on the butting face  20  on the opposite side, as illustrated in  FIG. 3 . Thus, compressed air which has flowed from the fluid port  23   a  flows out from the fluid port  23   b  on an outflow side having foreign matter as well as moisture removed by the filter element. 
     The flanges  21  and  22  are each formed in a substantially-square shape, and clamp portions  24  are provided on two sides of each of the flanges  21  and  22  oriented vertically and positioned in parallel with each other, and clamp grooves  25  are formed between the clamp portions  24  and the coupling head  14 . Guide portions  26  are provided on both ends of each of upper sides of the flanges  21  and  22 , while guide portions  27  are provided on both ends of each of lower sides of the flanges  21  and  22 . Guide grooves  28  are formed between the guide portions  26  and the coupling head  14 , while guide grooves  29  are formed between the guide portions  27  and the coupling head  14 . The guide groove  28  configures a first recessed guide portion, while the guide groove  29  configures a second recessed guide portion. 
     As illustrated in  FIG. 5 , the guide groove  28  on the upper side is set to have a length of a dimension L 1 , while the guide groove  29  on the lower side is set to have a length of a dimension L 2 , and the upper and lower guide grooves  28  and  29  are different in length from each other, and they are different in shape from each other. A central portion of the guide portion  26  connects to a protrusion  14   a  of the coupling head  14 , and a bottom face of the guide groove  28  is defined by the protrusion  14   a . Similarly, a bottom face of the guide groove  29  is defined by a protrusion  14   b.    
     In this manner, the guide grooves  28  and  29  different in length dimension are provided on lower and upper sides of the coupling head  14  of the filter  10  having a vertical directionality, respectively. Since the lubricator  12  illustrated in  FIG. 1  also has a vertical directionality as described above, the coupling head  16  is provided with the flanges  21  and  22  having a shape similar to that of the filter  10 . 
     Flanges  31  and  32  each having a butting face  30  are provided on two side faces of the coupling head  18  of the regulator  11  positioned on opposite sides of the coupling head  18 . As illustrated in  FIG. 2 , a fluid port  33   a  on an inflow side is opened on the butting face  30  of one flange  31 , while a fluid port  33   b  on an outflow side is opened on the butting face  30  on the opposite side, as illustrated in  FIG. 6 . Thus, compressed air which has flowed from the fluid port  33   a  is adjusted regarding its pressure to flow out from the fluid port  33   b  on an outflow side. 
     The flanges  31  and  32  are each formed in a substantially-square shape, and a dimension L of each side thereof is set to substantially the same dimension as that of the respective sides of the flanges  21  and  22 . Clamp portions  34  are provided on four sides of each of the flanges  31  and  32 , and clamp grooves  35  are provided between the clamp portions  34  and the coupling head  18 . Thus, the flanges  31  and  32 , each being symmetrical regarding a vertical direction and a horizontal direction, are provided on the coupling head  18  of the regulator  11  having no vertical directionality, and the clamp grooves  35  are provided along entire peripheral faces of the flanges  31  and  32 . 
     As illustrated in  FIG. 3 , a wedge face  36  inclined from the outside of the clamp portion  24  to the inside of the same toward the coupling head  14  is formed on an inner face of the clamp portion  24  of the filter  10 . As illustrated in  FIG. 4 , a guide face  37  inclined in a direction similar to that of the wedge face  36  is formed on each of inner faces of the guide portions  26  and  27  of the filter  10 . As illustrated in  FIGS. 3 and 4 , a wedge face  38  inclined toward the coupling head  18  according to a direction from the outside of the clamp portion  34  to the inside of the same is formed to an inner face of the clamp portion  34  of the regulator  11 . 
     As illustrated in  FIG. 2 , the connector  13  has a coupling block  41 . The coupling block  41  has a spacer portion  43  formed with seal faces  42  on both faces thereof to contact the butting face  20  of the filter  10  and the butting face  30  of the regulator  11 , respectively, and the spacer portion  43  has dimensions corresponding to those of the flanges  22  and  31 . The spacer portion  43  is formed with a through-hole  44  which causes the fluid port  23   b  of the filter  10  and the fluid port  33   a  of the regulator  11  to communicate with each other. 
     As illustrated in  FIGS. 2 to 4 , concentric seal grooves  45  are formed on the respective seal faces  42  so as to surround the through-hole  44 , and seal members  46  which seal between the respective seal faces  42  and the butting faces  20  and  30  are attached to the seal grooves  45 . Thereby, the respective fluid ports  23   b  and  33   a  are caused to communicate with the through-hole  44  in an air-tight manner. 
     The coupling block  41  has an operating portion  47  extending along one side of the spacer portion  43  and integrated with the spacer portion  43 . The operating portion  47  is set to have a thickness dimension which is larger than the thickness of the spacer portion  43  and is set such that the operating portion  47  can be inserted between the coupling heads  14  and  18 . As illustrated in  FIG. 2 , the coupling block  41  is integrally provided with a bracket  48  projecting from the operating portion  47 , and the bracket  48  is formed with a mounting hole  49 . The bracket  48  is provided on a lower side than the operating portion  47 , and the coupling block  41  is attached to the filter  10  such that the bracket  48  is positioned on a lower side than the filter  10 . Thus, the coupling block  41  has a vertical directionality and it is fixed at a predetermined installation position (not illustrated) by a fastening member such as a bolt attached to the mounting hole  49 . 
     Thus, the connector  13  has a function of coupling the filter  10  and the regulator  11  with each other, and a function of fixing these members at the installation position. Incidentally, the bracket  48  may be integrally provided on an upper side than the operating portion  47 , and in the case, the connector  13  is attached to the filter  10  such that the bracket  48  is positioned on an upper side. However, if only the function of coupling the filter  10  and the regulator  11  with each other is given to the connector  13 , it is unnecessary to provide the bracket  48 . 
     Tongue portions  51  are provided on the operating portion  47  so as to correspond to two faces of the spacer portion  43 , and each of the tongue portions  51  projects towards a side of the opposite side of the spacer portion  43 . The respective tongue portions  51  are each formed with a wedge face  52  selectively contacting one of the wedge face  36  of the clamp portion  24  and the wedge face  38  of the clamp portion  34 . 
     Guide protrusions  53  and  54  are provided on both upper end and lower ends of the operating portion  47  corresponding to two sides of the spacer portion  43 , and the respective guide protrusions  53  and  54  project from the operating portion  47  in parallel with the tongue portion  51 . The guide protrusion  53  configures a first guide protrusion, while the guide protrusion  54  configures a second guide protrusion. The guide protrusions  53  and  54  are each formed with an inclined guide face  55  selectively contacting one of the guide face  37  and the wedge face  38 . The guide protrusions  53  on the upper side each has the length L 1  corresponding to the guide groove  28  of the filter  10 , while the guide protrusions  54  on the lower side each has the length L 2  corresponding to the guide groove  29  of the filter  10 . Therefore, the coupling block  41  is attached to the filter  10  such that the bracket  48  is positioned on a lower side. On the other hand, since the clamp grooves  35 , each forming a recessed guide portion into which the guide protrusion is inserted, are formed over the entire periphery of the flange  31  in the regulator  11 , the regulator  11  can be attached to the coupling block  41  even if the handle  19  is oriented in any direction of downward, upward, rightward, or leftward directions in  FIG. 2 . 
     A fastening member  57  can be detachably attached to the coupling block  41 . The fastening member  57  has a width and a length corresponding to the operating portion  47 , and a mounting hole  60  is formed in the fastening member  57 , the mounting hole  60  being to be attached with a hexagon socket head cap bolt  59  connected to a screw hole  58  formed on an end face of the spacer portion  43  of the coupling block  41 . The fastening member  57  is fastened to the coupling block  41  by the bolt  59 . Tongue portions  61  corresponding to the respective tongue portions  51  are provided on inner faces of the fastening member  57  in a projecting manner. The tongue portions  61  are each formed with a wedge face  62  selectively contacting one of the wedge face  36  of the clamp portion  24  and the wedge face  38  of the clamp portion  34 . 
     Guide protrusions  63  and  64  are provided on both upper end and lower ends of the fastening member  57  so as to correspond to both the faces of the spacer portion  43 , and the respective guide protrusions  63  and  64  project from inner faces of the fastening member  57  in parallel with the tongue portion  61 . The respective guide protrusions  63  and  64  are formed with inclined guide faces  65  contacting the guide face  37  and the wedge face  38 . The guide protrusion  63  configures a third guide protrusion, while the guide protrusion  64  configures a fourth guide protrusion. The guide protrusions  63  on an upper side each has the length L 1  corresponding to the guide groove  28  of the filter  10 , while the guide protrusions  64  on a lower side each has the length L 2  corresponding to the guide groove  29  of the filter  10 . Therefore, the fastening member  57  is attached to the filter  10  such that the guide protrusions  63  on the upper side are positioned on an upper side. On the other hand, the regulator  11  can be attached to the fastening member  57  even if the handle  19  is oriented in any direction of downward, upward, rightward, or leftward directions in  FIG. 2 . 
     To couple the filter  10  and the regulator  11  to each other using the connector  13 , the coupling head  14  of the filter  10  and the coupling head  18  of the regulator  11  are attached to the coupling block  41 . At this time, the guide protrusion  53  serving as the first guide protrusion and extending along one face side of the spacer portion  43  is inserted into the guide groove  28  on the upper side, and the guide protrusion  54  serving as the second guide protrusion is inserted into the guide groove  29  on the lower side, such that the bracket  48  of the coupling block  41  and the bowl  15  of the filter  10  are positioned on the lower side in  FIG. 2 . Thereby, the wedge face  52  of the tongue portion  51  contacts the wedge face  36  of the clamp portion  24 . On the other hand, since the clamp grooves  35 , each forming the recessed guide portion between the clamp portions  34  on four sides of the regulator  11  and the coupling head  18 , are formed over the entire outer peripheral face of the flange  31 , the guide protrusion  53  serving as the first guide protrusion and extending along the other face side of the spacer portion  43  is inserted into the clamp groove  35  on the upper side, and the guide protrusion  54  serving as the second guide protrusion is inserted into the clamp groove  35  on the lower side. Thereby, the wedge face  52  of the tongue portion  51  contacts the wedge face  38  of the clamp portion  34 . 
     In this manner, the filter  10  and the regulator  11  are attached to the coupling block  41  at the respective coupling heads  14  and  18 . Since both the guide protrusions  53  and  54  can also be inserted into the clamp groove  35  on any side of the clamp grooves  35  on four sides formed between the clamp portions  34  and the coupling head  18 , attachment of the regulator  11  to the coupling block  41  can be performed in a downward direction where the handle  19  is positioned on a lower side, an upward direction where the handle  19  is positioned on an upper side, or a leftward or rightward direction where the handle  19  is oriented leftward or rightward. 
     To attach the fastening member  57  to the coupling block  41 , the guide protrusion  63  of the fastening member  57  serving as the third guide protrusion is inserted into the guide groove  28  on the upper side, and the guide protrusion  64  serving as the fourth guide protrusion is inserted into the guide groove  29  on the lower side. Thereby, the wedge face  62  of the tongue portion  61  contacts the wedge face  36  of the clamp portion  24 . On the other hand, the guide protrusion  63  serving as the other third guide protrusion is inserted into the clamp groove  35  on the upper side, and the guide protrusion  64  serving as the other fourth guide protrusion is inserted into the clamp groove  35  on the lower side. Thereby, the wedge face  62  of the tongue portion  61  contacts the wedge face  38  of the clamp portion  34 . By jointing the bolt  59  to the screw hole  58  by screwing under this situation, the coupling block  41  and the fastening member  57  are fastened to each other so as to come close to each other, and the filter  10  and the regulator  11  are coupled to each other in an air-tight manner by the connector  13 . 
     When the air treatment unit composed of the filter  10  and the regulator  11  is installed at an installation site, the connector  13  is fastened to the installation site in a state where the filter  10  and the regulator  11  have been coupled to each other by the connector  13 . However, such a configuration can be adopted that the fastening member  57  is attached to the coupling block  41  after the filter  10  and the regulator  11  are assembled to the coupling block  41  of the connector  13  in a state where the connector  13  has been preliminarily fastened to the installation site. In any of the cases, the air treatment unit is installed such that the bowl  15  of the filter  10  is positioned on a lower side. 
     As illustrated in  FIG. 1 , when the air treatment unit composed of the filter  10 , the regulator  11  and the lubricator  12  is installed at the installation position, the lubricator  12  is coupled to the regulator  11  using still another connector  13 . A pipe on an upstream side is connected to the filter  10  of the air treatment unit illustrated in  FIG. 1  by the connector  13 , and an end of the pipe is provided with a connection joint having a flange in the same shape as that of the flanges  21 ,  22  or the flanges  31 ,  32 . The lubricator  12  of the air treatment unit is connected to a pipe on a downstream side by the connector  13 , and an end of the pipe is provided with a connection joint having a flange with the same shape as that of the flanges  21 ,  22  or the flanges  31 ,  32 . Similarly, in the air treatment unit composed of the filter  10  and the regulator  11 , a pipe on an upstream side is coupled to the filter  10  by the connector  13 , and a pipe on a downstream side is coupled to the regulator  11  by the connector  13 . 
       FIG. 9  is a sectional view illustrating a state that the positional relationship of the filter  10  having a vertical directionality is vertically inverted with respect to the coupling block  41  and the fastening member  57 . When the guide protrusion  53  of the coupling block  41  is inserted into the guide groove  29  and the guide protrusion  54  is inserted into the guide groove  28 , the long guide protrusion  53  of the coupling block  41  abuts on the bottom face of the short guide groove  29 , so that the coupling block  41  cannot be assembled up to an assembling-completion position. Similarly, when the guide protrusion  63  of the fastening member  57  is inserted into the guide groove  29  and the guide protrusion  64  is inserted into the guide groove  28 , the fastening member  57  cannot be assembled up to an assembling-completion position. Therefore, a worker is prevented from assembling the filter  10  and the connector  13  in a state that the positional relationship of the filter  10  and the connector  13  is upside-down. On the other hand, the regulator  11  having no vertical directionality can be attached to the connector  13  in any posture of upward, downward, rightward, or leftward. 
       FIG. 10  illustrates the air treatment unit in which the filter  10  and the lubricator  12  are coupled to each other by a connector  13  and the regulator  11  is coupled to the lubricator  12  by another connector  13 . The filter  10  and the lubricator  12  have vertical directionalities, respectively, and when these members are attached to the connector  13 , they are coupled to each other such that their bowls  15  and  17  are provided next to each other. On the other hand, the regulator  11  has no vertical directionality, and thus the regulator  11  can be attached to the connector  13  such that the handle  19  is positioned on an upper side, as illustrated in  FIG. 10 . When the attachment is performed in this manner such that the handle  19  is positioned on the upper side, a space below the regulator  11  is effectively utilized so that another apparatus can be arranged in the space. 
     The connector  13  is not only capable of coupling a fluid apparatus having a vertical directionality and a fluid apparatus having no vertical directionality to each other, but also capable of coupling two fluid apparatuses each having a vertical directionality to each other as well as coupling two fluid apparatuses each having no vertical directionality to each other. 
       FIG. 11  is an exploded perspective view illustrating a connector according to another embodiment,  FIGS. 12A and 12B  are a side view of a filter viewed from a direction of the arrow  12 A in  FIG. 11  and a front view of the same viewed from a direction of the arrow  12 B in  FIG. 11 , respectively, and  FIGS. 13A and 13B  are a side view of a coupling block viewed from a direction of the arrow  13 A in  FIG. 11  and a front view of the same viewed from a direction of the arrow  13 B in  FIG. 11 , respectively. 
     As illustrated in  FIG. 11 , flanges  21  and  22  of a filter  10  have a shape similar to those of the flanges  31  and  32  of a regulator  11 , and a guide portion  26  on an upper side of each of the flanges  21 ,  22  and a guide portion  27  on a lower side of the same are provided over an entire length L of the sides, respectively. A protrusion  66  projecting horizontally toward a butting face  20  is provided on an upper end of the coupling head  14 , and a width dimension of the guide groove  28  is defined by the protrusion  66 . On the other hand, a mounting ring portion  67  integrally provided at a lower end of a coupling head  18  for mounting the coupling head  18  and a bowl guard  15   a  projects toward a position substantially flush with the butting face  20 , and a width dimension of the guide groove  29  is set by the mounting ring portion  67 . 
     As illustrated in  FIG. 12B , the guide groove  28  of the upper side is set to have a width of a dimension T 1 , the guide groove  29  on the lower side is set to have a dimension T 2  smaller than the size T 1 , and the upper and lower guide grooves  28  and  29  are different in width dimension and shape from each other. The upper and lower guide grooves  28  and  29  different in width dimension are provided on the coupling head  14  of the filter  10  having a vertical directionality. 
     The flanges  31  and  32  symmetrical in vertical and horizontal directions are provided on the coupling head  18  of the regulator  11  having no vertical directionality. Therefore, the respective clamp grooves  35  of the regulator  11  are similar to those of the regulator  11  illustrated in  FIG. 2 , and width dimensions of the clamp grooves  35  are not specifically limited. 
     Upper guide protrusions  53  provided on an operating portion  47  have the width T 1  corresponding to the guide groove  28  of the filter  10 , respectively, and lower guide protrusions  54  have the width T 2  corresponding to the guide groove  29  of the filter  10 , respectively. Therefore, a coupling block  41  is attached to the filter  10  such that a bracket  48  is positioned on a lower side. On the other hand, since the clamp grooves  35  are not limited in widthwise directions, respectively, the regulator  11  is attached to the coupling block  41  even if a handle  19  is oriented in any direction of downward, upward, rightward, or leftward in  FIG. 11 . 
     Similarly, upper guide protrusions  63  provided on a fastening member  57  have the width T 1  corresponding to the guide groove  28  of the filter  10 , respectively, and lower guide protrusions  64  have the width T 2  corresponding to the guide groove  29  of the filter  10 , respectively. Therefore, the fastening member  57  is attached to the filter  10  such that the upper guide protrusions  63  are positioned on an upper side. On the other hand, the regulator  11  is attached to the fastening member  57  even if the handle  19  is oriented in any direction of downward, upward, rightward, or leftward in  FIG. 11 . 
       FIG. 14  is a front view illustrating a state where the positional relationship of the coupling block  41  is vertically inverted with respect to the filter  10  having a vertical directionality. When it is tried to insert the guide protrusion  53  of the coupling block  41  into the guide groove  29  and insert the guide protrusion  54  into the guide groove  28 , the thick guide protrusion  53  of the coupling block  41  cannot be inserted into the thin guide groove  29 , so that the coupling block  41  cannot be attached to the filter  10 . Regarding the fastening member  57 , since the guide protrusion  63  cannot be inserted into the guide groove  29  like described the above, the fastening member  57  cannot be attached. Therefore, a worker is prevented from assembling the filter  10  and the connector  13  to each other in a state that the mutual positional relationship of the filter  10  and the connector  13  is upside-down. On the other hand, the regulator  11  having no vertical directionality can be attached to the connector  13  in any posture of upward, downward, rightward, or leftward. 
       FIG. 15  is an exploded perspective view illustrating a connector according to another embodiment,  FIGS. 16A and 16B  are a front view and a side view of a filter, respectively,  FIGS. 17A and 17B  are a front view and a side view of a regulator, respectively,  FIG. 18A  is a side view of a coupling block and a fastening member, and  FIG. 18B  is a front view of the coupling block. 
     As illustrated in  FIGS. 15 ,  16 A, and  16 B, protrusions, each having a substantially-square butting face  20 , are provided on two side faces being positioned on the opposite sides of the filter  10 , and flanges  21  and  22 , each having four fastening faces corresponding to four sides of the butting faces  20 , are formed of the protrusions. Clamp grooves  25  are formed on two fastening faces of each of the flanges  21  and  22  oriented vertically and in parallel with each other, so that clamp portions  24  are formed on corresponding two sides by the clamp grooves  25 . The respective clamp grooves  25  do not extend up to both ends of the fastening faces, they are provided only at central portions of the fastening faces in a longitudinal direction, and guide holes  70  with a circular shape in section are provided to be opened on the flanges  21  and  22  at upper ends of the fastening faces. In the flanges  21  and  22  of the filter  10  having a vertical directionality, thus, the guide holes  70  serving as recessed guide portions are provided only on the upper ends of two fastening faces oriented vertically and in parallel with each other, so that an upper portion and a lower portion the filter  10  are formed to be different in shape. 
     As illustrated in  FIGS. 15 ,  17 A and  17 B, as with the butting face  20 , protrusions each having a substantially-square butting face  30  and each side of the butting face  30  having a dimension M, are provided being positioned on the opposite sides on two side faces of the regulator  11 , and flanges  31  and  32 , and flanges  31  and  32 , each having four fastening faces corresponding to four sides of the butting faces  20 , are formed of the protrusions. Clamp grooves  35  are formed on four fastening faces of each of the flanges  31  and  32 , and clamp portions  34  are formed on corresponding four sides by the clamp grooves  35 . The respective clamp grooves  35  do not extend up to both ends of the fastening faces, provided on central portions of the fastening faces in a longitudinal direction, and guide holes  72  having a circular shape in section are provided to be opened on the flanges  31  and  32  at both ends of the fastening faces. In the flanges  31  and  32  of the regulator  11  having no vertical directionality, thus, the guide holes  72  serving as recessed guide portions are provided on both ends of each of the four fastening faces, so that a shape symmetrical in vertical and horizontal directions is formed. 
     As illustrated in  FIG. 15 , a spacer portion  43  of a coupling block  41  is formed in substantially square shape having each side with a dimension M corresponding to the flanges  22  and  31 , and brackets  48  formed with mounting holes  49  are protruded and provided on both upper and lower sides of an operating portion  47 . Guide protrusions  73  are provided above tongue portions  51  provided on a central portion of the operating portion  47 , namely, on an upper end of the operating portion  47 , so as to correspond to both faces of the spacer portion  43 . Thus, the guide protrusions  73  are protruded from an inner face of the operating portion  47  in parallel with the tongue portion  51 , and they are each formed in a circular shape in section corresponding to the guide hole  70  of the filter  10 . Since the guide protrusions  73  are provided only on the upper end of the operating portion  47  in this manner, the coupling block  41  has a vertical directionality, and it is attached to the filter  10  such that the guide protrusions  73  are positioned on an upper side. On the other hand, since the guide holes  72  are provided on both ends of each of the four fastening faces in the regulator  11 , the regulator  11  can be attached to the coupling block  41  even if the handle  19  is oriented in any direction of a vertical direction or a horizontal direction. 
     Similarly, guide protrusions  75  having a circular shape in section corresponding to the guide protrusions  73  of the coupling block  41  are provided on an upper end of a fastening member  57 . Therefore, the fastening member  57  is attached to the filter  10  such that the guide protrusions  75  are positioned on an upper side. On the other hand, since the guide holes  72  are provided on both ends of each of the four fastening faces in the regulator  11 , the regulator  11  can be attached to the coupling block  41  even if the handle  19  is oriented in any direction of a vertical direction and a horizontal direction. 
     In this manner, since the guide protrusions  73  and  75  are provided on the connector  13  corresponding to the guide holes  70  provided in the filter  10  having a vertical positional relationship, the guide protrusions  73  and  75  are inserted into the guide holes  70 , so that wedge faces  52  and  62  of the tongue portions  51  and  61  contact wedge faces  36  of the clamp portions  24  only when the vertical positions of the filter  10  and the connector  13  match. On the contrary, when it is tried to attach a connector  13  to the filter  10  in a state that the position of the connector  13  is vertically inverted with respect to the filter  10 , the guide protrusions  73  and  75  are oriented in a vertical direction and abut on two fastening faces parallel with each other, so that the connector  13  cannot be attached to the filter  10 . Therefore, a worker is prevented from assembling the filter  10  and the connector  13  in a state that the vertical positional relationship of the filter  10  and the connector  13  is mutually upside-down. 
     On the other hand, since the guide holes  72  into which the guide protrusions  73  and  75  can be inserted are provided on the both ends of each of four fastening faces of the regulator  11  having no vertical positional relationship, the connector  13  can be attached to the regulator  11  in any posture of upward, downward, leftward, or rightward. Incidentally, such a configuration may be adopted that the guide holes  70  are provided only on lower ends of two fastening faces oriented in a vertical direction of the filter  10  and in parallel with each other and the guide protrusions  73  and  75  are provided only on the lower ends of the operating portion  47  of the coupling block  41  and the fastening member  57 . 
       FIGS. 19A to 21B  illustrate a filter, a regulator and a connector according to another embodiment.  FIGS. 19A and 19B  are a front view and a side view of the filter,  FIGS. 20A and 20B  are a front view and a side view of the regulator,  FIG. 21A  is a side view of a coupling block and a fastening member, and  FIG. 21B  is a front view of the coupling block. 
     As illustrated in  FIGS. 19A and 19B , flanges  21  and  22  of a filter  10  are each formed in a shape substantially the same as those of the flanges  21  and  22  of the filter  10  illustrated in  FIG. 16 . Guide holes  70  having a circular shape in section and a length dimension M 1  are opened at upper ends of two fastening faces oriented vertically and in parallel with each other, namely, above clamp grooves  25 , and guide holes  71  having a circular shape in section and a length dimension M 2  longer than that of the guide hole  70  are opened at lower ends of the fastening faces, namely, below the clamp grooves  25 . Thus, the guide holes  70  and  71  different in length dimension are provided in the flanges  21  and  22  of the filter  10  having a vertical directionality on the upper end and the lower end of two fastening faces oriented vertically and in parallel with each other, respectively, so that the upper portion and the lower portion of the flanges  21  and  22  are different in shape. The guide hole  70  forms a first recessed guide portion, while the guide hole  71  forms a second recessed guide portion. 
     As illustrated in  FIGS. 20A and 20B , flanges  31  and  32  of a regulator  11  is each formed in a shape substantially the same as those of the flanges  31  and  32  of the regulator  11  illustrated in  FIG. 17 . Two guide holes  72  are opened at both ends of each of four fastening faces so as to sandwich a clamp groove  35 , and the guide hole  72  has the length dimension M 2  and a circular shape in section like the guide hole  71 . Thus, the guide holes  72  serving as recessed guide portions are provided in the flanges  31  and  32  of the regulator  11  having no vertical directionality on both the ends of each of four fastening faces, so that a shape symmetrical in vertical and horizontal directions can be obtained. 
     As illustrated in  FIGS. 21A and 21B , a spacer portion  43  of a coupling block  41  is formed in a shape substantially the same as that of the coupling block  41  illustrated in  FIGS. 18A and 18B , and guide protrusions  73  and  74  are provided at an upper end and a lower end of an operating portion  47  corresponding to both faces of the spacer portion  43 . The guide protrusion  73  on the upper side has the length dimension M 1  and a circular shape in section corresponding to the guide hole  70 , while the guide protrusion  74  on the lower side has the length dimension M 2  and a circular shape in section corresponding to the guide hole  71 . Thus, since the coupling block  41  includes the guide protrusions  73  and  74  different in length dimension and provided at the upper end and the lower end, respectively, the coupling block  41  has a vertical directionality, so that the coupling block  41  is attached to the filter  10  such that the guide protrusions  73  are positioned on an upper side while the guide protrusions  74  are positioned on a lower side. On the other hand, since guide holes  72  into which both the guide protrusions  73  and  74  can be inserted, respectively, are provided on both ends of each of four fastening faces in the regulator  11 , the regulator  11  is attached to the coupling block  41  even if the handle  19  is oriented in any direction of a vertical direction or a horizontal direction. The guide protrusion  73  configures a first guide protrusion while the guide protrusion  74  configures a second guide protrusion. 
     Similarly, guide protrusions  75  having a circular shape in section and the length dimension M 1  and guide protrusions  76  having a circular shape in section and the length dimension M 2  which correspond to the guide protrusions  73  and  74  of the coupling block  41  are provided on an upper end and a lower end of a fastening member  57 . Therefore, the fastening member  57  is attached to the filter  10  such that the guide protrusions  75  are positioned on an upper side, while the guide protrusions  76  are positioned on a lower side. On the other hand, since guide holes  72  into which both the guide protrusions  75  and  76  can be inserted, respectively, are provided on both the ends of each of four fastening faces in the regulator  11 , the regulator  11  can be attached to the coupling block  41  even if the handle  19  is oriented in any direction of a vertical direction or a horizontal direction. The guide protrusion  75  configures a third guide protrusion, while the guide protrusion  76  configures a fourth guide protrusion. 
     Thus, since the guide protrusions  73  to  76  are provided on a connector  13  corresponding to the guide holes  70  and  71  provided on the filter  10  having a vertical positional relationship, the guide protrusions  73  to  76  are inserted into the guide holes  70  and  71  so that wedge faces  52  and  62  of tongue portions  51  and  61  contact wedge faces  36  of a clamp portion  24  only when the vertical positions of the filter  10  and the connector  13  match. On the contrary, when it is tried to attach the connector  13  to the filter  10  in a state that the position of the connector  13  is vertically inverted with respect to the filter  10 , the guide protrusions  74  and  76  are not inserted into the guide holes  70  completely, so that the connector  13  cannot be attached to the filter  10 . Therefore, a worker is prevented from assembling the filter  10  and the connector  13  in a state that the vertical positional relationship of the filter  10  and the connector  13  is upside-down. 
     On the other hand, since guide holes  72  into which any one of the guide protrusions  73  to  76  can be inserted are provided on both ends of each of four fastening faces in the regulator  11  having no vertical positional relationship, the connector  13  can be attached to the regulator  11  in any posture of upward, downward, rightward, or leftward. Incidentally, such a configuration may be adopted that the vertical positional relationship of the guide holes  70  and  71  of the filter  10  is inverted and the vertical positional relationship of the guide protrusions  73  and  74  and the guide protrusions  75  and  76  of the connector  13  is inverted. 
       FIGS. 22A to 24B  illustrate a filter, a regulator and a connector according to another embodiment.  FIGS. 22A and 22B  are a front view and a side view of the filter, respectively,  FIGS. 23A and 23B  are a front view and a side view of the regulator, respectively,  FIG. 24A  is a side view of a coupling block and a fastening member, and  FIG. 24B  is a front view of the coupling block. 
     As illustrated in  FIGS. 22A and 22B , flanges  21  and  22  of a filter  10  are each formed in a shape substantially the same as those of the flanges  21  and  22  of the filter  10  illustrated in  FIGS. 16A and 16B . Guide holes  70  having a circular shape in section and a diameter D are opened at upper ends of two fastening faces oriented vertically and in parallel with each other, namely, above clamp grooves  25 , and guide holes  71  having a square shape in section and the dimension of one side D are opened at lower ends of the fastening faces, namely, below the clamp grooves  25 . Thus, the guide holes  70  and  71  different in sectional shape are provided in the flanges  21  and  22  of the filter  10  having a vertical directionality on upper ends and lower ends of two fastening faces oriented vertically and in parallel with each other, so that the upper portion and the lower portion of the filter  10  are different in shape. 
     As illustrated in  FIGS. 23A and 23B , flanges  31  and  32  of a regulator  11  are each formed in a shape substantially the same as those of the flanges  31  and  32  of the regulator  11  illustrated in  FIGS. 17A and 17B . Two guide holes  72  are formed at both ends of each of four fastening faces so as to sandwich a clamp groove  35 , and the guide hole  72  is formed in a square shape in section having one side of the dimension D like the guide hole  71 . Thus, the guide holes  72  are provided in the flanges  31  and  32  of the regulator  11  having no vertical directionality on both the ends of each of four fastening faces, so that a shape symmetrical in vertical and horizontal directions is obtained. 
     As illustrated in  FIGS. 24A and 24B , a spacer portion  43  of a coupling block  41  is formed in a shape approximately similar to that of the coupling block  41  illustrated in  FIGS. 18A and 18B , and guide protrusions  73  and  74  are provided at an upper end and a lower end of an operating portion  47  corresponding to both faces of the spacer portion  43 . The guide protrusion  73  on the upper side has a circular shape in section with a diameter D corresponding to the guide hole  70 , while the guide protrusion  74  on the lower side has a square shape in section with one side of a size D corresponding to the guide hole  71 . Thus, since the coupling block  41  includes the guide protrusions  73  and  74  different in sectional shape provided on the upper end and the lower end thereof, respectively, the coupling block  41  has a vertical directionality, so that the coupling block  41  is attached to the filter  10  such that the guide protrusions  73  are positioned on an upper side, while the guide protrusions  74  are positioned on a lower side. On the other hand, since the guide holes  72  into which both the guide protrusions  73  and  74  can be inserted are provided on both ends of each of the four fastening faces in the regulator  11 , the regulator  11  is attached to the coupling block  41  even if the handle  19  is oriented in any direction of a vertical direction or a horizontal direction. 
     Similarly, guide protrusions  75  having a circular shape in section and the diameter D and guide protrusions  76  having a square shape in section and one side of the dimension D which correspond to the guide protrusions  73  and  74  of the coupling block  41  are provided on an upper end and a lower end of a fastening member  57 . Therefore, the fastening member  57  is attached to the filter  10  such that the guide protrusions  75  are positioned on an upper side, while the guide protrusions  76  are positioned on a lower side. On the other hand, since guide holes  72  into which both the guide protrusions  75  and  76  can be inserted are provided on both the ends of each of the four fastening faces in the regulator  11 , the regulator  11  can be attached to the coupling block  41  even if the handle  19  is oriented in any direction of a vertical direction or a horizontal direction. 
     Thus, since the guide protrusions  73  to  76  are provided on the connector  13  corresponding to the guide holes  70  and  71  provided on the filter  10  having a vertical positional relationship, the guide protrusions  73  to  76  are inserted into the guide holes  70  and  71  so that wedge faces  52  and  62  of tongue portions  51  and  61  contact wedge faces  36  of clamp portion  24  only when the vertical positions of the filter  10  and the connector  13  match. On the contrary, when it is tried to attach the connector  13  to the filter  10  in a state that the vertical positional relationship of the connector  13  and the filter  10  is inverted, the guide protrusions  74  and  76  cannot be inserted into the guide holes  70 , so that the connector  13  cannot be attached to the filter  10 . Therefore, a worker is prevented from assembling the filter  10  and the connector  13  in a state that the vertical positional relation of the filter  10  and the connector  13  is mutually upside-down. 
     On the other hand, since guide holes  72  into which any one of the guide protrusions  73  to  76  can be inserted are provided on both ends of each of the four fastening faces in the regulator  11  having no vertical positional relationship, the connector  13  can be attached to the regulator  11  in any posture of upward, downward, rightward, or leftward. Incidentally, such a configuration may be adopted that the vertical positional relationship of the guide holes  70  and  71  of the filter  10  is inverted and the vertical positional relationship of the guide protrusions  73  and  74  and the guide protrusions  75  and  76  of the connector  13  is inverted. 
       FIGS. 25A to 27B  illustrate a filter, a regulator and a connector according to another embodiment.  FIGS. 25A and 25B  are a front view and a side view of the filter, respectively,  FIGS. 26A and 26B  are a front view and a side view of the regulator, respectively,  FIG. 27A  is a side view of a coupling block and a fastening member, and  FIG. 27B  is a front view of the coupling block. 
     As illustrated in  FIGS. 25A and 25B , flanges  21  and  22  of a filter  10  are each formed in a shape substantially the same as those of the flanges  21  and  22  of the filter  10  illustrated in  FIGS. 16A and 16B . Guide holes  70  having a circular shape in section and a diameter D 1  are opened at upper ends of two fastening faces oriented vertically and in parallel with each other, namely, above clamp grooves  25 , and guide holes  71  having a circular shape in section and a diameter D 2  larger than the diameter of the guide hole  70  are opened at lower ends of the fastening faces, namely, below the clamp grooves  25 . Thus, the guide holes  70  and  71  different in sectional shape, respectively, are provided in the flanges  21  and  22  of the filter  10  having a vertical directionality on upper ends and lower ends of the two fastening faces oriented vertically and in parallel with each other, so that the upper portion and the lower portion of the filter  10  are different in shape. 
     As illustrated in  FIGS. 26A and 26B , flanges  31  and  32  of a regulator  11  are each formed in a shape substantially the same as those of the flanges  31  and  32  of the regulator  11  illustrated in  FIGS. 17A and 17B . Two guide holes  72  are opened at both ends of each of four fastening faces so as to sandwich a clamp groove  35 , and the guide holes  72  are formed in a circular shape in section having the diameter D 2  like the guide hole  71 . Thus, the guide holes  72  are provided in the flanges  31  and  32  of the regulator  11  having no vertical directionality on both the ends of each of the four fastening faces, so that a shape symmetrical in vertical and horizontal directions can be obtained. 
     As illustrated in  FIGS. 27A and 27B , a spacer portion  43  of a coupling block  41  is formed in a shape substantially the same as that of the coupling block  41  illustrated in  FIGS. 18A and 18B , and guide protrusions  73  and  74  are provided at an upper end and a lower end of an operating portion  47  corresponding to both faces of the spacer portion  43 . The guide protrusion  73  on the upper side has a circular shape in section having the diameter D 1  corresponding to the guide hole  70 , while the guide protrusion  74  on the lower side has a circular shape in section having the diameter D 2  corresponding to the guide hole  71 . Thus, since the coupling block  41  includes the guide protrusions  73  and  74  different in sectional shape provided on the upper end and the lower end thereof, respectively, the coupling block  41  has a vertical directionality so that the coupling block  41  is attached to the filter  10  such that the guide protrusions  73  are positioned on an upper side, while the guide protrusions  74  are positioned on a lower side. On the other hand, since the guide holes  72  into which both the guide protrusions  73  and  74  can be inserted are provided on both ends of each of the four fastening faces in the regulator  11 , the regulator  11  is attached to the coupling block  41  even if the handle  19  is oriented in any direction of a vertical direction or a horizontal direction. 
     Similarly, guide protrusions  75  having a circular shape in section and the diameter D 1  and guide protrusions  76  having a circular shape in section and the diameter D 2  which correspond to the guide protrusions  73  and  74  of the coupling block  41  are provided on an upper end and a lower end of a fastening member  57 . Therefore, the fastening member  57  is attached to the filter  10  such that the guide protrusions  75  are positioned on an upper side while the guide protrusions  76  are positioned on a lower side. On the other hand, since the guide holes  72  into which both the guide protrusions  75  and  76  can be inserted are provided on both the ends of each of the four fastening faces in the regulator  11 , the regulator  11  can be attached to the coupling block  41  even if the handle  19  is oriented in any direction of a vertical direction or a horizontal direction. 
     Thus, since the guide protrusions  73  to  76  are provided on the connector  13  corresponding to the guide holes  70  and  71  provided on the filter  10  having a vertical positional relationship, the guide protrusions  73  to  76  are inserted into the guide holes  70  and  71  so that wedge faces  52  and  62  of tongue portions  51  and  61  contact wedge faces  36  of a clamp portion  24  only when vertical positions of the filter  10  and the connector  13  match. On the contrary, when it is tried to attach the connector  13  to the filter  10  in a state that the vertical positional relationship of the connector  13  to the filter  10  is inverted, the guide grooves  74  and  76  cannot be inserted into the guide holes  70 , so that the connector  13  cannot be attached to the filter  10 . Therefore, a worker is prevented from assembling the filter  10  and the connector  13  in a state that the mutual vertical positional relationship of the filter  10  and the connector  13  is inverted. 
     On the other hand, since the guide holes  72  into which any one of the guide protrusions  73  to  76  can be inserted are provided on both ends of each of the four fastening faces in the regulator  11  having no vertical positional relationship, the connector  13  can be attached to the regulator  11  in any posture of upward, downward, rightward, or leftward. Incidentally, such a configuration may be adopted that the vertical positional relationship of the guide holes  70  and  71  of the filter  10  is inverted and the vertical positional relationship of the guide protrusions  73  and  74  and the guide protrusions  75  and  76  of the connector  13  is inverted. 
     INDUSTRIAL APPLICABILITY 
     The present invention is not limited to the foregoing embodiments and various modifications can be made within the scope of the present invention. For example, coupling of a fluid apparatus other than the filter  10 , the regulator  11  and the lubricator  12  can be performed, where a fluid apparatus having a directionality is provided with a flange similar to that of the filter  10  or the lubricator  12 , while a fluid apparatus having no directionality is provided with a flange similar to that of the regulator  11 . As the fluid apparatus having no directionality, there are various valves such as a residual pressure exhaust valve other than a pressure reducing value, namely, the regulator  11 . Further, the shapes of the upper guide groove  28  and  29  or the guide holes  70  and  71  of the filter  10  and the lubricator  12  can be modified variously as far as they are different from each other. 
     While the present invention 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 invention may be made without departing from the spirit and scope of the present.