Abstract:
A terminal block assembly includes an actuator member that is displaceable relative to a terminal block housing to transport an insulated conductor toward the insulating penetrating knife edges of a stationary electrical contact mounted within the housing, characterized by the provision of a guide pin and guide groove arrangement for guiding the actuator member during the displacement thereof relative to the housing.

Description:
REFERENCE TO RELATED APPLICATION 
     This application is a companion application to the U.S. application of Peter Stuckmann, et al., Ser. No. 09/950,603 filed Sep. 13, 2001, entitled “Terminal Block with Disconnect Contact and Terminal Arrangement”. 
    
    
     SPECIFICATION 
     Field of the Invention 
     A terminal block assembly includes an actuator member that is displaceable relative to a terminal block housing to transport an insulated conductor into engagement with the knife edges of a stationary electrical contact on the terminal block, thereby to effect penetration of the insulation and electrical connection between the conductor and the stationary contact, characterized by the provision of guide means for guiding the actuator member during the movement thereof relative to said terminal block housing. 
     BACKGROUND OF THE INVENTION 
     Brief Description of the Prior Art 
     A terminal block with a connecting device that penetrates the insulation layer of an insulated conductor is disclosed in the German published application No. 196 27 209. The connecting device illustrated in this publication features contact cutters with cutting edges that widen to form contacting surfaces. The contacting surfaces facilitate a larger-surface contacting of the line lead(s) of the connected electrical conductor than do the actual contact cutters used in severing the conductor, which essentially touch the conductor in a “linear fashion.” 
     The solution offered in German Patent No. DE 197 32 182 C1 proved effective in order further to support the outside resiliency of the connecting devices. This publication discloses, among other things, a cutting terminal contact with a contact spring having two elastic contact legs that define a contact slit where a U-shaped support spring is provided that has plate-shaped spring legs. The U-shaped support spring or overspring is designed as a part that is separated from the actual contact or the resilient contact. The plate-shaped spring legs essentially are aligned normal to the cutting terminal or the contacting areas of the contact legs and encompass the latter along the contact slit over a predetermined width. 
     European Patent No. EP 0 936 697 A1 discloses a typical terminal block. The contact springs are made each time on both ends of a bus bar, which is so aligned in the housing made of insulation material that the insertion openings of the two resilient stationary contacts point away f rom each other, that is to say, a conductor is introduced into the resilient contact from the outside with relation to the mounting rail. To make the actual introduction of the conductors into the contact springs easier, there are provided contact activation pieces that are arranged on the top of the housing that is made of insulation material. The contact activation pieces are made in the form of a slide and are inserted in the housing made of insulation material from the outside upon first assembly. Each has a conductor introduction opening, and under an essentially U-shaped recess in the foot area, it has lateral catch surfaces as well as a deep stop for the conductor. 
     Dovetail-like guides are made in the upper opening area of the housing made of insulation material; the contact activation piece is guided in a movable manner on these guides with bilaterally corresponding dovetail grooves. The contact activation piece can be shifted by means of a screwdriver between a conductor insertion position and a contacting position and these two positions are defined by a catch position. 
     This terminal block and its connecting devices generally have proven to be effective. For various practical purposes, however, it is desirable to so develop the design structure of the terminal block and the connecting device that one can make terminal blocks with particularly small dimensions. In particular, the dimensions of the metal subassembly of the connecting device should be made as compact as possible, and the forces that are introduced into the insulation material housing of the terminal block should also be kept as small as possible. The task of the present invention is to solve this problem. 
     SUMMARY OF THE INVENTION 
     Accordingly, a primary object of the present invention is to provide a terminal block assembly including an actuator member that carries an insulated conductor between disengaged and engaged positions relative to a stationary contact supported within a chamber contained in the terminal block, characterized in that the actuator member is guided by guide pin and groove means for pivotal or linear movement relative to the terminal block housing. The guide pins extend laterally from the actuator for engagement with the guide grooves contained in opposing walls of the terminal block. Both the actuator member and the terminal block are formed from electrically insulating synthetic plastic material. The guide means prevent jamming of the actuator relative to the terminal block, and the length of the guide grooves may be reduced as compared with a pure shifting of the actuator member without any guide means. 
     Another object of the invention is to arrange the stationary resilient contacts on inwardly directed end portions of the bus bar, with the respective actuator members being arranged between the stationary contacts. In this manner, only pressure forces act on the actuator members during the displacement thereof between their engaged and disengaged portions relative to the stationary contacts. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Other objects and advantages of the invention will become apparent from a study of the following specification when viewed in the light of the accompanying drawings, in which: 
     FIGS. 1 a - 1   e  are side elevational views of the terminal block illustrating the manner of operation of the actuator member from the disengaged position toward the engaged position, thereby to displace an insulated conductor toward the knife edges of the stationary resilient contact; 
     FIGS. 2 a - 2   c  illustrate the displacement of the actuator member from the engaged position toward the disengaged condition; 
     FIGS. 3 a - 3   c  are side elevation, end, and top views, respectively, of the actuator member of FIG. 1; 
     FIGS. 4 and 5 are side elevation and exploded views, respectively, of the terminal block assembly of FIG. 1; 
     FIGS. 6 a - 6   c  are detailed views illustrating the displacement of the actuator member by the operating tool from the disengaged position to the engaged position; 
     FIGS. 7 a  and  7   b  are detailed views illustrating the displacement of the actuator member by the operating tool from the engaged position to the disengaged position; 
     FIGS. 8 a - 8   c  are detailed views illustrating the pivotal displacement of the actuator member of another embodiment of the invention by the operating tool from the disengaged position to the engaged position; 
     FIG. 9 is an elevational view illustrating the operation of a further embodiment of the terminal block assembly of the present invention; 
     FIG. 10 is an exploded view of the support spring and actuator member; 
     FIG. 11 is a sectional view illustrating the dovetail guide means of another embodiment of the invention; and 
     FIG. 12 is a side elevation view of another terminal block assembly embodiment according to the present invention. 
    
    
     DETAILED DESCRIPTION 
     Referring first more particularly to FIGS. 1 a - 1   e , the terminal block assembly  2  of the present invention includes a terminal block housing  4  that is formed of synthetic plastic insulating material and within which is mounted a bus bar  14  that extends between electrical connections  10  and  12  at opposite ends of the terminal block. The bus bar  14  carries a pair of inwardly directed opposed stationary resilient contacts  15  the adjacent extremities of which are provided with knife edges  16  that are operable to penetrate the insulation layer of electrical conductors  36  that are associated with the connector means  10  and  12 , respectively. A pair if U-shaped resilient support springs  22  are provided at each of the connector means  10  and  12  for laterally supporting the stationary contacts  15  relative to the terminal block housing  4 , respectively. Moveably mounted within chambers  28  (FIG. 5) contained in opposite ends of the housing  4  are a pair of actuator members  26 . When the actuator member  26  is in the disengaged position of FIG. 1 a , an insulated conductor  36  may be longitudinally inserted within a bore  34  (FIG. 3 c ) that extends vertically through the actuator member  26 . When an operating tool  42  (such as the tip of a screwdriver) is inserted into chamber  28  on the left hand side of the actuator member  26 , the actuator member is pivoted in the clockwise direction to displace the conductor  36  toward the knife edges  16  of the stationary spring contact  15 . As the tool  42  is progressively inserted within the opening contained in the housing  4 , the tip of the tool engages an inclined downwardly directed internal surface  44  of the housing chamber  28 , and progressively pivots the actuator member  26  to the right to the position of FIG. 1 c , wherein the knife edges  16  penetrate the insulating layer of the conductor  36 . Upon further insertion of the operating tool  42 , the tip is supported adjacent the bus bar  14  as shown in FIG. 1 c , and further displacement of the tool to the right causes pivotal movement of the operating member  26  to the right to the fully engaged position of FIG. 1 e . During this movement of the actuator  26  and the conductor  36  relative to the stationary contact  15 , the stationary contact is laterally supported by the upper extremities of the legs of the U-shaped support spring  22 . 
     Similarly, as shown in FIGS. 2 a - 2   c , after the tip of the operating tool  42  (such as a screwdriver) is inserted to the right of the actuator member  26  in the fully engaged position of FIG. 2 a , the operating tool is pivoted to the right as shown in FIG. 2 b , thereby to displace the actuating member to the left together with the conductor  36  carried thereby, and thus effect disengagement of the conductor from the stationary resilient contact  15 . When the actuator member  26  is completely pivoted to the left to the disengaged position of FIG. 2 c , the conductor  36  is released from the stationary contact  15  for vertical removal from the actuating member  26 . 
     Referring now to FIGS. 3 a - 3   c , the actuator member  26  contains a vertical bore  34  for receiving the insulated conductor  36 , as well as lateral slots  54   a  and  54   b  for receiving the insulated outer surface of the conductor  36 . The lower end of the actuator member  26  contains a recess  38  that defines the conductor support wall  39  for laterally supporting the lower end of the insulated conductor  36 . In accordance with a characterizing feature of the present invention guide pins  30  are provided that extend laterally outwardly from opposite sides of the actuator member into corresponding guide grooves  32  contained in the opposed side walls of the housing chamber  28 . The operating member  26  contains groove  40  for receiving the knife edges  16  when the actuator member is in the fully engaged position of FIG. 1 e.    
     As shown in FIGS. 4 and 5, a pair of the actuator members  26  are provided at opposite ends of the terminal block housing  4 , and a pair of the support springs  22  support the stationary resilient contacts  15  within the terminal block housing  4 , respectively. The guide slots  32  are provided intermediate their ends with raised tapered portions  47  that cooperate with the guide pins to retain the actuator members in one of their engaged or disengaged positions. 
     Referring now to FIGS. 5, the support contacts  15  are carried by reversely inwardly bent end portions of the bus bar, whereby the knife edges  16  of the stationary resilient contacts  15  are directed toward each other. The stationary resilient contacts  15  are bifurcated by a longitudinally extending slit  18  that extends within the contact portion  20  of the stationary contact. The lateral sides of the contact portion  20  of the stationary contacts  15  contain recesses for receiving the upper extremities of the leg portions of the support springs  22 . 
     Referring now to FIGS. 6 a - 6   c , when the actuator member  26  is in the disengaged position of FIG. 6 a , the insulated conductor is inserted downwardly within the vertical bore contained within the actuator  26 , whereupon an operating tool  42 , such as the tip of a screwdriver, is inserted in the gap G between the right hand end of the actuator member and the adjacent end wall of chamber  28 . As the tool is progressively inserted downwardly into the chamber, the tip of the tool engages the downwardly inclined wall surface  44  to progressively displace actuator member  26  linearly to the left until the conductor  36  is brought into engagement with the knife edges  16  of the stationary contact  15 . These knife edges penetrate the layers of insulation and come into contact with the electrical conductor. As the tool  42  is further inserted into the chamber  28 , the tip of the tool eventually engages the bus bar  14  and the actuator member  26  is in the fully-engaged position of FIG. 6 c . At this time, a locking extension  50  carried by the actuator member  26  extends into the locking recess  52  container in the adjacent end wall surface of the chamber  28 , thereby to lock the actuator member in the engaged position. 
     As shown in FIG. 7 a , in order to displace the actuator member  26  linearly to the right toward the disengaged position, the tip of the tool  42  is introduced into the gap G′ between the left of the actuator member and the adjacent end wall of chamber  28 . The tool  42  is pivoted to the left about the fulcrum defined by housing portion  4   a , locking projection  50  is disengaged from locking recess  52 , and actuator member  26  and conductor  36  are displaced to the right toward the fully disengaged position of FIG. 7 b.    
     As shown in FIGS. 8 a - 8   c , the guide grooves  32 ′ may be bent or curved for guiding the actuator member for pivotal movement along a curved path relative to the terminal block housing  4 . In this embodiment, the portion  14   a  of the bus bar is supported by the abutment W carried by the support spring  22  through which the bus bar extends. As the tip of the operating tool  42  is progressively introduced into chamber  28  and the tip of the tool engages the downwardly inclined surface  44 , the actuator member is pivoted to the right toward the fully engaged position of FIG. 8 c . As shown in phantom, to pivotally displace the actuator member  26  toward the disengaged position, the operating tool is introduced into chamber  28  on the right side of the actuator member  26 , and the tool is pivoted in the clockwise direction about the fulcrum defined by the mouth portion of the opening, whereupon the actuator member is pivoted toward the disengaged position of FIG. 8 a.    
     Referring to the modification of FIG. 9, the bus bar  14  includes a linear first portion  62  that extends between the support springs  22 , and a pair of end sections  67  that are generally Z-shaped. To retain the support springs  22  in place, a protrusion  64  thereof (FIG. 10) extends between a corresponding abutment  66  carried by the terminal block housing, as shown in FIG.  9 . The mounting feet portion of the terminal block are connected with outwardly directed flanges of the U-shaped mounting rail  60 , as is known in the art. In accordance with an important feature of the invention, the housing includes a protective edge portion  68  that extends in spaced relation above the stationary contact  15 , thereby to prevent the engagement of the contact by the tip of the operating tool  42 . 
     As shown in FIG. 11, the guide means may be of the dovetail tongue and groove type, wherein the beveled edges  56   b  of the guide pins  30  engage corresponding beveled edges  56   a  in the guide slots  32 . Similarly, an upper dovetail connector may be provided by the beveled surfaces  58   a  and  58   b  in the grooves defined in the actuator body above the guide pins. 
     Referring to FIG. 12, it will be seen that by the use of the Z-shaped bus bar sections  67 , various numbers of stationary contacts  15  may be supported in spaced relation along the linear bus bar section  64 . 
     While in accordance with the provisions of the Patent Statutes the preferred forms and embodiments of the invention have been illustrated and described, it will be apparent to those skilled in the art that various changes may be made without deviating from the inventive concepts set forth above.