Patent Publication Number: US-6210238-B1

Title: Wire connection apparatus for solenoid-operated valves

Description:
This application is a continuation of Ser. No. 09/205,363 filed Dec. 4, 1998, now U.S. Pat. No. 6,017,249. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a wire connection apparatus for connecting feeding leads from an external power supply to a solenoid valve installed on a valve installation member such as a sub-plate or a manifold. 
     PRIOR ART 
     An example of a known wire connection apparatus for connecting feeding leads to a solenoid valve installed on a valve installation member, such as a sub-plate or a manifold, is a plug-in feeding apparatus in which a solenoid valve is installed on the valve installation member so that a receiving connector provided in the solenoid valve is electrically connected to a connector to a terminal block mounted on the valve installation member. 
     FIG. 11 shows an example of a well-known plug-in feeding apparatus. A valve installation member  61  having a solenoid-operated valve installed on its top surface includes a terminal block  62  mounted at one longitudinal end and a cover  63  covering the terminal block. The terminal block  62  has a plurality of feeding terminals  64  to which leads (not shown) are connected, and the cover  63  has an introduction hole  63   a  through which the leads are introduced. 
     When the solenoid-operated valve  60  is installed on the valve installation member  61 , the pins in a receiving terminal (not shown) provided in the solenoid valve are electrically connected to a connector (not shown) provided in a terminal block. 
     In this well-known feeding apparatus, when the leads, which have been passed through the introduction hole  63   a  in the cover  63 , are connected to the plurality of feeding terminals  64  provided in the terminal block  62  and if an attempt is made to perform this connection operation when the solenoid-operated valve  60  is installed on the valve installation member  61 , the operation must be performed in a narrow space under the solenoid valve  60  and is thus difficult. Consequently, the connection of the leads and the replacement of the terminal block are cumbersome, and the reliability of the connections is low. 
     OBJECTS OF THE INVENTION 
     It is an object of this invention to provide a wire connection apparatus that is reliable and safe for use in feeding electricity and that enables feeding leads to be connected simply, reliably, and safely to a solenoid valve that is placed on the valve installation member. 
     To achieve this object, this invention provides a wire connection apparatus comprising a terminal block accommodation chamber in a valve installation member, a cover member detachably mounted on the opening of the terminal block accommodation chamber, and a terminal block that is formed integrally with the cover member and that is loaded in and unloaded from the terminal block accommodation chamber when the cover is installed and removed, respectively. 
     An introduction port through which feeding leads are drawn is provided in the cover member, and a plurality of feeding terminals to which the drawn leads are connected are provided on the terminal block. A plurality of contacts extend from the respective terminals, and a plurality of contacts leading to a solenoid-operated valve are provided in a first connector installed in the terminal block accommodation chamber so that when the terminal block is inserted into the accommodation chamber, the contacts of the terminal block and the contacts of the first connector are connected together. 
     In this invention configured in the above manner, the cover member is removed from the valve installation member to remove the terminal block from the accommodation chamber, and the feeding leads inserted into the introduction port in the cover member are connected to the respective feeding terminals. Subsequently, when the cover member is mounted on the opening of the accommodation chamber, the terminal block is inserted into the accommodation chamber to connect the contacts of the terminal block and the contacts of the first connector together, and the solenoid valve is connected to the feeding leads via the terminal block and first connector. 
     Thus, according to this invention, since the leads can be connected to the respective feeding terminals of the terminal block in a space outside the terminal accommodation chamber, connection operations can be simply and reliably performed even if the solenoid valve is installed on the valve installation member. 
     In addition, since each feeding terminal and the first connector are automatically connected together by inserting the wire-connected terminal block into the terminal block accommodation chamber, connection operations are simple and no connection error occurs. Electrical reliability is therefore improved. 
     Moreover, the terminal block can be loaded and unloaded via the cover member by simply installing and removing the cover member. Thus, handling is simple and this apparatus is safe because the operator does not need to directly touch the terminal block. 
     According to one specific embodiment of this invention, the terminal block has a base extending from behind the cover member. The plurality of feeding terminals are provided on the tip of the base horizontally in parallel. In addition, the contacts of the terminal block and the contacts of the first connector are shaped like plugs and sockets, respectively, that can be fitted together. The contacts of the terminal block are entirely surrounded by a cylindrical protective frame having an open front surface, and the contacts of the first connector are disposed horizontally in parallel inside a connector body mounted in the valve installation member. When the tip of the first connector is fitted in the protective frame, the contacts are connected together. 
     According to another specific embodiment, a second connector electrically connected to the first connector is provided on the top surface of the valve installation member so that when the solenoid is placed on the valve installation member, the connector of the solenoid valve is connected to the second connector. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a sectional view of the integral part of a first embodiment of this invention. 
     FIG. 2 is an enlarged view of the integral part in FIG. 1 showing that leads are connected to the apparatus. 
     FIG. 3 is a sectional view showing that a terminal block is removed. 
     FIG. 4 is a perspective view of FIG. 3 in a partly exploded form. 
     FIG. 5 is a top view of a second connector. 
     FIG. 6 is a perspective view of the integral part of a second embodiment of this invention. 
     FIG. 7 is a sectional view of a separated state showing a third embodiment of this invention. 
     FIG. 8 is a sectional view of a connected state of the third embodiment. 
     FIG. 9 is a perspective view of the third embodiment in a partly exploded form. 
     FIG. 10 is a perspective view showing that the components in FIG. 9 are integrally assembled together. 
     FIG. 11 is a perspective view of the integral part of a well-known feeding apparatus. 
    
    
     DETAILED DESCRIPTION 
     FIGS. 1 to  5  show a first embodiment of a wire connection apparatus according to this invention. A wire connection apparatus  3  is provided at one end of a sub-plate, which is an example of a valve installation member, and power is fed to a solenoid valve  2  on the sub-plate  1  via the connection apparatus  3 . 
     The sub-plate  1  comprises a supply port P and ejection ports EA and EB for a pressure fluid that are opened toward the reader, output ports A and B for a pressure fluid that are opened in the direction opposite to the reader, and an external pilot supply port X and a pilot ejection port PE that are opened in an end surface opposite to the connection apparatus  3 . Each of these ports is opened in a solenoid-operated valve installation surface of the sub-plate  1 . 
     The connection apparatus  3  has a terminal block accommodation chamber  4  formed at one end of the sub-plate  1 , a cover member  14  detachably mounted on an opening  4   a  in the front surface of the accommodation chamber  4 , a terminal block  15  formed integrally with the cover member  14 , and a relay connection means  23  for electrically connecting the terminal block  15  and the solenoid-operated valve  2 . 
     The terminal block accommodation chamber  4  is formed in such a way as to have the opening  4   a  in one end surface of the sub-plate  1 , and the relay connection means  23  is accommodated inside the terminal block accommodation chamber  4  beforehand. The relay connection means  23  consists of a first connector  6  electrically connected to the terminal block  15 , a second connector  8  connected to the solenoid-operated block  2 , and a lead  13  that is a conductive member for electrically connecting connectors  6  and  8  together. 
     The second connector  8  is provided upward in the connector accommodation chamber  5 , which is opened in the top surface of the sub-plate  1 . As shown in FIG. 5, the second connector  8  comprises a main body section  8   a  that appears to be almost square from above and that is inserted into the opening  5   a  of the connector accommodation chamber  5 ; a mounting section  8   b  that is larger than the main body section, that appears to be almost square from above, and that is engagingly locked in a connector mounting groove  5   b ; and a cylindrical portion  8   c  located between the main body section and the mounting section. The second connector is mounted in the connector accommodation chamber  5  by inserting it into the chamber  5  from the terminal block accommodation chamber side  4  and rotating it through about 45° to engagingly lock the corners of the mounting section  8   b  in the connector mounting groove  5   b . The second connector  8  has a plurality of socket terminals  9  in which pin-shaped terminals  35   a  are provided on a receiving connector  35  of the solenoid valve  2 . 
     The first connector  6  is held by a mounting plate  10  that is fixed to a protrusion  4   b  in the rear of the terminal block accommodation chamber  4  using a plurality of set screws  10   a . In the first connector  6 , a contact  28  extending from each feeding terminal  18  of the terminal block  15  and a plurality of contacts  7  shaped like connectable sockets are provided horizontally in parallel, and each contact  7  and each socket terminal  9  of the second connector  8  are connected together via the lead  13 . 
     The terminal block  15  is formed integrally with the cover member  14  so as to be loaded in and unloaded from the terminal block accommodation chamber  4  by mounting it on and removing it from the accommodation chamber  4 , respectively. The terminal block  15  has a base  15   a  extending from behind the cover member  14 , and the feeding terminals  18  shaped like screws are provided on the tip of the base  15  horizontally in parallel so that feeding leads  16  drawn through a lead introduction port  17  in the cover member  14  are connected to these feeding terminals  18 . 
     Each feeding terminal  18  has a nut  25  into which the terminal is screwed and a washer  26  located between the terminal and the nut. The plug-shaped contact  28  for electric connection is attached to each feeding terminal  18  in such a way as to extend outward, and the contacts  28  are entirely surrounded by a cylindrical protective frame  29  having an open front surface. With the tip of the connector  6  fitted in the protective frame  29 , each plug-shaped contact  28  is fitted in the corresponding socket-shaped contact shoe  7  of the first connector  6  for connection. 
     In addition, the cover member  14  comprises two positioning protrusions  19  formed at diagonal positions, two bolt through-holes  20 , and a seal member  21  for sealing the periphery of the opening  4   a  of the terminal block accommodation chamber  4 . The cover member  14  can be mounted on the sub-plate  1  by inserting the positioning protrusions  19  into positioning holes provided in the sub-plate  1  to determine a mounting position, and tightening set screws  22  passing through the bolt through-holes  20 . 
     The solenoid-operated valve  2  installed on the sub-plate  1  is a pilot-type 5-port directional control valve. The solenoid-operated valve  2  comprises a main valve  31 , a solenoid-driven pilot valve  32 , and an amplifying valve between the main valve and the pilot valve. In addition, changing the mounting position of the switching plate  34  enables a pilot fluid supplied to the pilot valve  32  to be switched between an internal pilot fluid supplied from the supply port P and an external pilot fluid supplied from the external pilot supply port X. The plug-in receiving connector  35  having a plurality of (in the illustrated example, 5) pin-shaped connection terminals  35   a  is provided on the bottom surface of the pilot valve  32 . 
     When the solenoid valve  2  is installed on the sub-plate  1  via a gasket, each port provided in the solenoid valve  2  communicates with the opening of a corresponding port in the sub-plate  1  in an airtight manner, and the plurality of pin-shaped terminals  35   a  of the receiving connector  35  are each inserted into the socket terminal  9  of the second connector  8  for electric connection. 
     The solenoid-operated valve  2  is not limited to a pilot-type 5-port directional control valve. 
     Reference numeral  36  in FIG. 4 designates a seal member that seals the connection portion between the receiving connector  35  and the second connector  8  and that is fitted and mounted around the opening of the connector accommodation chamber  5 . 
     The valve installation member according to this invention is not limited to the sub-plate  1  but may be a manifold instead. 
     According to the first embodiment, when the feeding leads  16  from an external power supply are connected to the terminal block  15 , the cover member  14  is removed to draw the terminal block  15  from the accommodation chamber  4 , and the leads  16  drawn through the introduction port  17  in the cover member  15  to the terminal block  15  are each connected to the respective feeding terminal  18  with or without a crimp terminal  16   a , as shown in FIGS. 3 and 4. 
     As a result, the leads  16  can be connected in a space outside the terminal block accommodation chamber  4 , so this connection operation is easy even if the solenoid-operated valve  2  is mounted on the sub-plate  1  beforehand. 
     When the terminal block  15  to which the leads  16  are connected is accommodated in the terminal block  15  and the cover member  14  is fixed to the opening  4   a  of the accommodation chamber  4 , the plug-shaped contact  28  extending from each feeding terminal  18  of the terminal block  15  is automatically fitted in the corresponding socket-shaped contact  7  of the first connector  6  for electric connection. Then, the tip of the first connector  6  is fitted in the protective frame  29  at the tip of the terminal block  15 . 
     Thus, the leads  16  can be connected to the respective feeding terminals  18  very easily. In addition, since the terminal block  15  can be loaded in and unloaded from the terminal block accommodation chamber  4  by simply opening and closing the cover member  14 , respectively, the operator does not need to directly touch the terminal block. Therefore, the safety of this apparatus is improved. Moreover, by simply pressing the terminal block  15  into the accommodation chamber  4  using the cover member  14 , the terminal block  15  to which the leads  16  are connected can be automatically connected to the first connector  6  leading to the solenoid-operated valve  2 . Consequently, the connection operation is simple and is not subject to connection errors. 
     FIG. 6 shows a cover member  14 A and a terminal block  15 A according to a second embodiment. Although in the first embodiment the cover member  14  and the base  15   a  of the terminal block  15  are integrated, in the second embodiment the base  15   a  of the terminal block  15 A is formed separately from the cover member  14 A and these components are coupled together using screws  40  passing through mounting sections  39 . 
     The other configuration is the same as in the first embodiment, so the same components have the same reference numerals and their description is omitted. 
     By forming the terminal block  15 A and the cover member  14 A separately and coupling them together, these components can be manufactured easily. 
     In this case, the leads may be connected to the respective feeding terminals  18  with the terminal block  15 A coupled to the cover member  14 A. Alternatively, the leads may be connected with the terminal block  15 A separated from the cover member  14 A, followed by the mounting of the terminal block  15 A on the cover member  14 A. 
     FIGS. 7 to  10  show a third embodiment of this invention. The third embodiment differs from the first embodiment in that each contact  28 B in a terminal block  15 B is shaped like a socket while each contact  7 B in a first connector  6 B is shaped like a plug, resulting in a slight difference in the configuration of the relay connection means. 
     That is, a second connector  8 B in the relay connection means  23 B comprises a main body section  44   a  that appears to be square from above, a base  44   b  having a larger diameter than the main body section, and engagement grooves  44   c  in two opposed sides of the base  44   b.    
     A first connector  6 B has a first body  46  and a second body  47  each having an L-shaped cross section. A recessed portion  48  in which the base  44   b  of the second connector  8  is fitted is formed in the middle of the upper end of each body  46  or  47 , and the recessed portion  48  includes a protrusion  48   a  that is engaged with the engagement groove  44   c . A plurality of pin-shaped contacts  7 B are provided between the bodies  46  and  47 , and are connected to the socket terminal  9  in the second connector  8 B via conductive members  13 B integrated with the contacts  7 B. 
     In addition, the first body  46  has a notch  46   a  through which a perpendicularly extending portion of each conductive member  13 B passes, and also has, in its horizontal portion  46   c , a plurality of grooves  46   b  in which each contact  7 B, which is formed by bending each conductive member  13 B in the horizontal direction, is fitted. The second body  47  comprises a horizontal portion  47   a  located under the horizontal portion  46   c  of the first body  46  to cover the openings of the grooves  46   b , and a plurality of protrusions  47   b  for reinforcing and positioning. 
     The tip of the contact shoe  28 B connected to each feeding terminal  18  of the terminal block  15 B is shaped like a socket into which the corresponding contact  7 B of the first connector  6 B can be inserted. 
     By accommodating a relay connection means  23 B according to this invention in the terminal block accommodation chamber  4  and accommodating the main body section  44   a  of the second connector  8 B in the connector accommodation chamber  5   a , the relay connection means  23 B can be mounted on the rear wall of the terminal block accommodation chamber  4  using set screws  55  passing through a plurality of through-holes  54  provided in the first and second bodies  46  and  47 . In this case, since the first connector  6 B and the second connector  8 B are coupled together, they enable easy mounting on the sub-plate  1 . 
     The remaining configuration and operation of the third embodiment are substantially the same as those in the first embodiment, so the same major components have the same reference numerals and their description is omitted. 
     Of course, in the third embodiment, the cover member  14 B and the terminal block  15 B may be separately formed and subsequently coupled together.