Patent Publication Number: US-4223193-A

Title: Device for representing status of push button switch

Description:
This application is a continuation of our copending application Ser. No. 810,173 filed June 27, 1977. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to a representation device for a push-button type switch. 
     The invention aims at providing a device of a simple structure and of a low manufacturing cost for representing the status of a push-button type switch. 
     In a known conventional device for this purpose, as shown in FIGS. 1A and 1B, a push button A is provided with an window section 12 made of a transparent material. A slide groove 14 is provided between an operation rod attaching section 13 and the window section 12, and between the operation rod attaching section 13 and a push-button section. A representing member 17 has one end clamped by a coiled spring retainer 15 and a switch housing 16, and the other end received by the slide groove 14. 
     As shown in FIG. 1A, the colour, for example black, of the operation rod attaching section 13 appears through the window section 12, in the state of the switch before being operated. 
     As the switch is depressed to the operating state as shown in FIG. 1B, the end portion of the representing member 17 is moved by a distance corresponding to the stroke of the push button A, and comes to be recognized through the window section. The representing member 17 has a specific colour, for example red, thereby to indicate that the switch has been turned to the operating state. 
     In this type of representation device, the stroke, or relative distance moved, of the representing member is equal to that of the push button. Therefore when the stroke of the switch is relatively small, it is difficult to provide a distinctive representation using a large area of the window section, resulting in an ambiguous representation. 
     It is therefore an object of the present invention to overcome the above described shortcoming of the prior art by providing a representation device in which the distance or stroke of the representing member is made larger than that of the push button, thereby to provide distinctive representation. 
     The above and other objects, as well as advantageous features of the invention will become more clear from the following description of a preferred embodiment taken in conjunction with the attached drawings in which: 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIGS. 1A and 1B are sectional side elevational views of essential parts of a conventional representation device, 
     FIG. 2 is an exploded perspective view of an essential part of a representation device in accordance with the present invention, and 
     FIG. 3A and FIG. 3B are sectional side elevational views of a representation device in accordance with the present invention explaining the manner of operation of the later. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to the drawings, a push button section 1 is made of a synthetic plastics material and is provided at its one side with an opening to which a transparent window section 2 is to be attached, and with at its other end another opening for receiving an attaching section of an operation rod. 
     A representing plate member 3 is made of an resilient material and has an arm 4. 
     The operation rod attaching section 5 has a projection 5a and a side wall in which a generally v-shaped groove 5b is formed. The projection 5a and the groove 5b are for attaching to the push button section 1. 
     A supporting member 6 is provided with two projections 6a,6a and a retaining section 6b. 
     Reference numerals 7,8,9 and 10 denote, respectively, a switch housing, an operation rod, a coiled spring and a frame made of a metallic plate. 
     In operation, referring at first to FIG. 3A showing the switch in the state before the operation, the representing member 3 is received by a groove B constituted by the push button section 1, the operation rod attaching section 5 and the window section 2, and cannot be observed through the window section 2. 
     In this state, the upper surface of the operating rod attaching section 5 appears through the window section 2. 
     The projection 4a formed at one end of the arm 4 of the representing member 3 is disposed in a bore 5c of the operation rod attaching section 5, so that the arm 4 may be pivoted within the groove 5b around a fulcrum constituted by the projection 4a. 
     The projections 6a,6a on the supporting member 6 are in contact with an area near the mid or central portion of the arm 4, while the retaining section 6b retains the frame 10. 
     As the push button is depressed in the direction of the arrow X from the state of FIG. 3A, the push button A is moved and is accompanied by the operation rod 8, so that one end of the arm 4 on the representing member 3 is also moved in the direction of the arrow X. 
     However, since the central portion of the arm 4 is clamped by the projections 6a,6a of the supporting member 6, the other end of the arm 4 where the representing member 3 is attached is moved in the direction of the arrow Y, so as to make the representing member 3 slide within the groove 4, to become positioned aligned with the window section 2 to effect the representation. 
     The switch has been changed-over within the housing 7, by the motion of the operation rod 8, and has been locked by a locking mechanism (not shown) provided, for example, on the housing 7. 
     Since the representing member 3 moves along the projections 6a,6a, and since the push button A itself moves, the stroke of the representing member becomes twice as large as that in the conventional device in which the stroke of the representing plate 3 is equal to that of the push button. 
     As the push button A is depressed again, at the state of FIG. 3B, the locking is dismissed to cause the reverse movement of the representing member 3, as well as the switch itself, to assume the state of FIG. 3A again. 
     As has been described, in the representation device of the invention, a representing member having an arm is provided within the switch, the arm being held at almost its central portion by a supporting member secured to the frame or the like, so that the representing member may be moved along a groove to become visible through a window for representing the status of the switch. 
     Since the representing member has an arm which is supported at its mid portion by a supporting member, the stroke of the representing member becomes sufficiently larger as compared with that of the conventional arrangement, so as to provide practically distinctive representation effect.