Patent Publication Number: US-9412528-B2

Title: Switch structure

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to a switch structure design, and more particularly to an improved switch (cam) device in which a lead can be inserted and electrically connected. The switch device has a restriction body for guiding the carrier body. The switch device is applicable to both flat-head terminal lead and bare lead. 
     2. Description of the Related Art 
     A conventional switch or cam switch is applied to electrical engineering, electronic engineering and automatic control system for an operator to controllably switch on/off the console. 
     The conventional switch includes an insulation housing  10  generally made of plastic material. The housing  10  is formed with multiple cavities  11  in which a conductive metal member  20 , a washer  30  assembled on the conductive metal member  20  and an adjustment screw  35  are mounted. In addition, the housing  10  is formed with multiple perforations  12  corresponding to the cavities  11  for the terminal leads to insert into the cavities  11 . By means of operating the screw  35 , the washer  30  is moved to press the terminal lead into electrical connection with the conductive metal member  20 . 
     As shown in  FIGS. 1 and 2 , a rotary switch  13  and a cam  14  are disposed on the housing  10 . When operating the rotary switch  13  to drive and rotate the cam  14 , an operator can selectively controllably switch on/off every conductive metal member  20  mounted in the cavity  11 . As known by those who are skilled in this field, multiple housings  10  can be stacked and plug-connected with each other to form multiple layers of housings  10 . For example, as shown in  FIG. 1 , the housings  10  are stacked and assembled to form two layers of housings  10 . 
     The conventional switch has a problem in structural design and application. That is, when multiple layers of housings  10  are applied to the automatic control system, the thickness or height of the housing  10  is limited within about 1 cm˜1.5 cm. Such limitation not only affects the operation space of the screw  35 , but also leads to limitation of the form of the lead inserted in the cavity  11  for electrically connecting with the conductive metal member  20 . 
     Please refer to  FIGS. 2 and 3 . In order to smoothly insert the terminal lead through the perforation  12  into the cavity  11  between the conductive metal member  20  and the washer  30 , an operator will instinctively unscrew the screw  35 . This often causes the screw  35  to drop out of the housing  10 . For overcoming this problem of the conventional switch, when manufacturing the washer  30 , the washer is punched and bent to form two arched wing sections  31  perpendicularly extending from the washer  30  for enclosing and restricting the screw  35  from dropping out of the housing  10  in operation. As known by those who are skilled in this field, this will complicate the structure of the washer  30  and increase the manufacturing cost of the washer  30 . Moreover, in order to easily punch and bent the washer  30  to form the arched wing sections  31 , the washer  30  must have a thin thickness (generally 0.6 mm). This lowers the structural strength of the washer  30  and deteriorates the ability to lock the terminal lead. This is not what we expect. 
     As aforesaid, when multiple layers of housings  10  are applied to the automatic control system, the thickness or height of the housing  10  is limited. This causes limitation of the operation space of the screw  35 . As a result, the washer  30  is only applicable to the flat-head terminal lead such as O-type or Y-type terminal lead. With respect to the bare lead with larger diameter or thickness, it is hard to insert the bare lead into the cavity  11  between the conductive metal member  20  and the washer  30 . 
     The conventional switch structure has some shortcomings in use and structural design that needs to be overcome. It is therefore tried by the applicant to provide an improved switch structure to eliminate the shortcomings existing in the conventional switch structure so as to improve the application and ensure the stability and lead locking ability of the switch structure. Under the limitation of the height of the housing, the switch structure of the present invention has an optimal structural strength and lead locking ability. Moreover, the switch structure of the present invention is simplified so that the manufacturing cost is lowered. In addition, the switch structure of the present invention is easily operable and applicable to both flat-head terminal lead (such as O-type or Y-type terminal lead) and bare lead. 
     SUMMARY OF THE INVENTION 
     It is therefore a primary object of the present invention to provide an improved switch structure connectable with both bare lead and flat-head terminal lead. The switch structure includes a main body formed with at least one cavity. A retainer member and a conductive metal member are arranged in the cavity for pressing the terminal lead into electrical connection with the conductive metal member. A reciprocally movable carrier body is assembled with the retainer member. The carrier body has an arm assembled with an elastic member. A restriction body is disposed in the cavity. The restriction body is formed with a chamber for receiving the arm and the elastic member of the carrier body, The restriction body restricts the moving direction or distance of the carrier body to increase the structural strength of the switch structure and enhance the lead locking ability of the switch structure. 
     In the above switch structure, the restriction body is formed with a chamber in which the arm and the elastic member of the carrier body are disposed. When operating the retainer member, the carrier body is pressed by the retainer member to reciprocally move along the chamber. Accordingly, the carrier body and the retainer member have a flexible operation space, permitting the flat-head terminal lead and bare lead to be inserted into the cavity between the conductive metal member and the carrier body and fixedly locked by the retainer member. 
     The present invention can be best understood through the following description and accompanying drawings, wherein: 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective assembled view of a conventional switch structure, showing that a rotary switch is assembled with the housing; 
         FIG. 2  is a perspective exploded view of the conventional switch structure, showing the housing, the conductive metal member and the washer of the switch in a 180-degree reversed state; 
         FIG. 3  is a sectional view of the conventional switch structure, showing the cooperation between the housing, the conductive metal member and the washer; 
         FIG. 4  is a perspective exploded view of the switch structure of the present invention, showing the main body, the conductive metal member and the carrier body of the switch structure in a 180-degree reversed state; 
         FIG. 5  is a sectional view of the switch structure of the present invention, showing the cooperation between the main body, the conductive metal member, the carrier body and the elastic member; 
         FIG. 6  is a sectional view of the switch structure of the present invention, showing that the retainer member drives the carrier body to move forward and the elastic member is compressed to store energy; 
         FIG. 7  is a sectional view of the switch structure of the present invention, showing that a flat-head terminal lead is locked between the carrier body and the conductive metal member, in which the flat-head terminal lead is O-type or Y-type terminal lead; and 
         FIG. 8  is a sectional view of the switch structure of the present invention, showing that a bare lead is locked between the carrier body and the conductive metal member. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Please refer to  FIGS. 4 and 5 . The switch structure of the present invention includes a main body  40  made of insulation material. The main body  40  is formed with multiple cavities  41  and perforations  42  corresponding to the cavities  41  for terminal leads to insert into the cavities  41 . In the cavities  41  are mounted conductive metal members  50 , carrier bodies  60  assembled with the conductive metal members  50  and retainer members  70 . 
     In this embodiment, the retainer member  70  is in the form of a screw. After the terminal lead is inserted into the cavity  41  through the perforation  42 , the retainer member  70  can be operated to make the carrier body  60  press and fix the terminal lead, whereby the terminal lead is electrically connected with the conductive metal member  50 . Moreover, as in the conventional operation mode, a cam  43  assembled on the main body  40  can be rotated to selectively controllably switch on/off every conductive metal member  50  mounted in the cavity  41 . 
     As shown in the drawings, the conductive metal member  50  includes a plane  51  and a pivot hole  52  (or threaded hole) formed on the plane  51 . When operating the retainer member  70  to move forward, the retainer member  70  is pivotally connected to the pivot hole  52 . The conductive metal member  50  has a contact pin  53  for electrically contacting a conductive plate  45  disposed in the main body  40  as shown in  FIG. 4 . 
     In this embodiment, the conductive metal member  50  is formed with a wall  54  normal to the plane  51  and a notch  55  formed on the wall  54 . The carrier body  60  is formed with a carrier face  61  and a neck section  63  protruding from the carrier face  61  corresponding to the plane  51  and notch  55  of the conductive metal member  50 . The neck section  63  is movable within the notch  55 . 
     To speak more specifically, the carrier face  61  is formed with a hole  62  corresponding to the pivot hole  52  of the conductive metal member  50  for assembling with the retainer member  70 . When operating the retainer member  70  to move forward, the retainer member  70  will press and move the carrier body  60  to make the neck section  63  move along the notch  55 . This will be further described hereinafter. 
       FIG. 4  also shows that the carrier body  60  has an arm  64  and a subsidiary arm  65  disposed at a rear end of the neck section  63  in parallel to each other. The arm  64  and the subsidiary arm  65  are normal to the carrier face  61 . In this embodiment, the arm  64  has a length shorter than that of the subsidiary arm  65 . An elastic member  66  is assembled with the arm  64 . The elastic member  66  has the form of a spring. 
     In a preferred embodiment, the cavity  41  is formed with a dent  44  in which a restriction body  80  is disposed for guiding the carrier body  60  to move a certain direction by a certain distance. The restriction body  80  can be integrally formed with the main body  40 . In consideration of the injection molding operation, alternatively, the restriction body  80  and the main body  40  can be two pieces that are assembled with each other. 
     To speak more specifically, the restriction body  80  has the form of a block body, formed with a chamber  81  and a guide channel  82  in adjacency to and in parallel to each other. The chamber  81  serves to receive the arm  64  and elastic member  66  of the carrier body  60 . The guide channel  82  serves to receive the subsidiary arm  65  and help in guiding the subsidiary arm  65  to move within the guide channel  82 . Accordingly, when operating the retainer member  70 , the carrier body  60  can be more stably reciprocally moved. 
     As shown in  FIG. 5 , the retainer member  70  is passed through the hole  62  of the carrier body and assembled with the carrier body.  FIG. 6  shows that when the retainer member  70  is moved forward, the retainer member  70  presses the carrier body  60  to move toward the plane  51  of the conductive metal member  50 . At the same time, the arm  64  of the carrier body  60  will compress the elastic member  66  to store energy.  FIG. 6  also shows that the retainer member  70  is tightened in the pivot hole  52  of the conductive metal member  50  and fixedly located. 
     It should be noted that the arm  64 , the elastic member  66  and the subsidiary arm  65  of the carrier body  60  are received in the chamber  81  and the guide channel  82  of the restriction body  80  as shown in  FIGS. 5 and 6 . Accordingly, when operating the retainer member  70 , the carrier body  60  is pressed by the retainer member  70  to reciprocally move along the chamber  81  and the guide channel  82 . In this case, the carrier body  60  and the retainer member  70  have a flexible operation space, permitting the flat-head terminal lead (such as O-type or Y-type terminal lead) and bare lead to be inserted into the cavity  41  between the conductive metal member  50  and the carrier body  60  and fixedly locked by the retainer member  70  as shown in  FIGS. 7 and 8 . 
     In comparison with the conventional switch structure, the switch structure of the present invention has the following advantages:
     1. The switch structure and the relevant components are redesigned and different from the conventional switch structure in use and operation form. For example, the main body  10  is formed with the dent  44  in which the restriction body  80  is disposed. The restriction body  80  is formed with a chamber  81  and a guide channel  82  for receiving the arm  64 , the elastic member  66  and the subsidiary arm  65  of the carrier body  60  respectively. The conductive metal member  50  is formed with a notch  55  and the neck section  63  of the carrier body is movable along the notch  55 . Accordingly, the application range of the present invention is widened and the structural strength of the present invention is increased to enhance the locking ability and facilitate the operation.   2. In the conventional switch structure, in order to prevent the screw from dropping out of the housing in operation, the washer must be punched and bent. This complicates the structure of the switch and increases the manufacturing cost of the switch. Also, the structural strength of the washer is lowered so that the locking ability for the terminal lead is deteriorated. In contrast, the present invention has higher structural strength so that the above problems are solved.   3. Under the limitation of the height of the switch or housing, the restriction body  80  and the carrier body  60  have such a cooperative structural form that a flexible operation space is formed between the carrier body  60 , the retainer member  70  and the conductive metal member  50 . Accordingly, the present invention is applicable to flat-head terminal lead such as O-type or Y-type terminal lead and/or bare lead. In contrast, the conventional switch structure is only applicable to flat-head terminal lead so that it is inconvenient for a user to choose the lead.   

     In conclusion, the switch structure of the present invention is different from the conventional switch structure in space form and is advantageous over the conventional switch structure. 
     The above embodiments are only used to illustrate the present invention, not intended to limit the scope thereof. Many modifications of the above embodiments can be made without departing from the spirit of the present invention.