Multiple push-button switch assembly with interlocking mechanism

An interlocking device for a push button switch, the push button switch including a switch body with fixed contacts, the push button switch having first and second push buttons which are downwardly movable in multiple stages by being pressed, each of the first and second push buttons having mobile contacts, said interlocking device comprising:

• a first interlocking member corresponding to the first push button, said first interlocking member including a projection;
• a second interlocking member corresponding to the second push button, said second interlocking member including a projection;
• and
• said first and second interlocking members facing each other and being synchronizingly swingable when the push buttons are pressed down;
• wherein
• when one of the push buttons is pressed down, said projection of the interlocking member corresponding to the pressed down push button prevents the swinging of the other interlocking member thereby preventing any simultaneous pressing down of the push buttons.

A push button switch comprising:

• a switch body with fixed contacts;
• first and second push buttons which are downwardly movable in multiple stages by being pressed, each of said first and second push buttons having mobile contacts;
• an interlocking device comprising
• a mobile contact interlocking member for preventing the contact of a mobile contact of at least one of said push buttons with a corresponding fixed contact when said first and second push buttons are pressed down simultaneously;
• said mobile contact interlocking member being provided on said switch body so that said mobile contact interlocking member swings on said switch body at a position which is relatively lower that said first and second push buttons;
• and
• said mobile contact interlocking member being connected to said switch body at approximately a mid-point between said first and second push buttons.

A push button switch comprising:

• a switch body with fixed contacts;
• first and second push buttons which are downwardly movable in multiple stages by being pressed, each of said first and second push buttons having mobile contacts;
• an interlocking device comprising
• a first interlocking member corresponding to said first push button, said first interlocking member including a projection;
• a second interlocking member corresponding to said second push button, said second interlocking member including a projection;
• and
• said first and second interlocking members facing each other and being synchronizingly swingable when said push buttons are pressed down;
• wherein
• when one of said push buttons is pressed down, said projection of the interlocking member corresponding to the pressed down push button prevents the swinging of the other interlocking member thereby preventing any simultaneous pressing down of said push buttons.