Abstract: In a case where a left-hand push-button switch is ON, a second relay RL2 is electrically de-energized to open a normally close contact RL2-1 of the second relay RL2 so that a relay contact circuit RC is opened. If, in this state, a right-hand push-button switch is shifted to a second OFF state, a normally close contact R3-1 of the right-hand push-button switch is opened. Thus, a third relay RL3 is not electrically de-energized and a first and a second circuits are in cutoff until both the right-hand and the left-hand push-button switches are returned to a first OFF state.

Abstract: A push-button switch 5 disposed in a switch case 3 has c-contacts and a normally close contact electrically connected with a terminal block 9 via conductors 39. Leading ends 23 of cores of a cable 7 introduced into the switch case 3 are inserted in insertion holes 49a, 49b formed in the terminal block 9. Screws 53a, 53b mounted to the terminal block 9 are tightened to press the leading ends 23 of the cores against conductive connection portions, on one side, in the insertion holes 49a, 49b, thereby to establish electrical connection.

Abstract: A push-button switch 5 disposed in a switch case 3 has c-contacts and a normally close contact electrically connected with a terminal block 9 via conductors 39. Leading ends 23 of cores of a cable 7 introduced into the switch case 3 are inserted in insertion holes 49a, 49b formed in the terminal block 9. Screws 53a, 53b mounted to the terminal block 9 are tightened to press the leading ends 23 of the cores against conductive connection portions, on one side, in the insertion holes 49a, 49b, thereby to establish electrical connection.

Abstract: An actuator of the present invention comprises an operation key 2 to be inserted into a key insertion hole formed in the safety switch, and a base 3. The operation key 2 is held on the base 3 and capable of freely swinging in two orthogonal directions. The actuator also comprises means (e.g. a guide stopper 4 and engagement spaces 34) for selectively restricting the swinging movement of the operation key 2 to either of the two directions.

Abstract: In a case where a left-hand push-button switch is ON, a second relay RL2 is electrically de-energized to open a normally close contact RL2-1 of the second relay RL2 so that a relay contact circuit RC is opened. If, in this state, a right-hand push-button switch is shifted to a second OFF state, a normally close contact R3-1 of the right-hand push-button switch is opened. Thus, a third relay RL3 is not electrically de-energized and a first and a second circuits are in cutoff until both the right-hand and the left-hand push-button switches are returned to a first OFF state.

Abstract: A push-button switch and a teaching pendant employing the same are provided. The push-button switch ensures that a push button is capable of switching ON/OFF the switch if one of contacts thereof should fail during an operation of the switch. For achieving this object, a switch case 3 contains two c-contacts 9a, 9b each having a snap action configuration and switching mechanisms 11a, 11b for opening/closing the c-contacts 9a, 9b. When a push button 5 is depressed, the switching mechanisms 11a, 11b simultaneously open/close the c-contacts 9a, 9b for turning ON/OFF a push-button switch 1.

Abstract: A push-button switch and a teaching pendant employing the same are provided. The push-button switch ensures that a push button is capable of switching ON/OFF the switch if one of contacts thereof should fail during an operation of the switch. For achieving this object, a switch case 3 contains two c-contacts 9a, 9b each having a snap action configuration and switching mechanisms 11a, 11b for opening/closing the c-contacts 9a, 9b. When a push button 5 is depressed, the switching mechanisms 11a, 11b simultaneously open/close the c-contacts 9a, 9b for turning ON/OFF a push-button switch 1.

Abstract: An actuator of the present invention comprises an operation key 2 to be inserted into a key insertion hole formed in the safety switch, and a base 3. The operation key 2 is held on the base 3 and capable of freely swinging in two orthogonal directions. The actuator also comprises means (e.g. a guide stopper 4 and engagement spaces 34) for selectively restricting the swinging movement of the operation key 2 to either of the two directions.

Abstract: The safety switch unit controls the source of power for machinery in accordance with the opening and closing of a room door. The safety switch includes an actuator (2) secured to a door, a cam shaft extending transversely of a direction in which the actuator (2) advances into the switch unit (1), the actuator (2) having a stepped top end in correspondence to which cam plates (13), (14a) and (14b) are provided within the switch unit (1) each capable of independently rotating, these cam plates having start sides (17) and (22) and a single cam follower pin (29) passed therethrough, thus protecting the switch unit (1) against mischievous or malicious operation.