Abstract: An expansion module of a programmable logic controller is provided. The expansion module comprises a function body and an expansion base. The function body comprises a housing, a circuit board and a first connector. The circuit board is disposed in the housing. The first connector is connected with the circuit board and is partially exposed from the housing. The expansion base is detachably assembled with the function body and comprises a bracket and a three-way connector. The three-way connector is detachably disposed in the bracket and comprises three conducting terminals. The first conducting terminal and the second conducting terminal are at least partially exposed from the bracket. The third conducting terminal is configured to connect with the first connector. When there are plural expansion modules, two adjacent function bodies can be detachably assembled with each other, and two adjacent expansion bases can be detachably assembled with each other.

Abstract: An electronic device is detachably mounted on a DIN rail. The DIN rail includes a first protruding edge and a second protruding edge. The electronic device includes a main body and two clips. The two clips are movably disposed on the main body. Each clip includes a base and an extension part. The base includes a notch. The notch is selectively engaged with or disengaged from the first protruding edge or the second protruding edge. The extension part is connected with the base and extended from the base. The extension part includes a double-bevel bulge and an elastic extension arm. The elastic extension arm is located beside the double-bevel bulge. A free end of the elastic extension arm has an engaging part. The notches of the two clips are engaged with or disengaged from the first protruding edge and the second protruding edge, respectively.

Abstract: An electronic device is detachably mounted on a DIN rail. The DIN rail includes a first protruding edge and a second protruding edge. The electronic device includes a main body and two clips. The two clips are movably disposed on the main body. Each clip includes a base and an extension part. The base includes a notch. The notch is selectively engaged with or disengaged from the first protruding edge or the second protruding edge. The extension part is connected with the base and extended from the base. The extension part includes a double-bevel bulge and an elastic extension arm. The elastic extension arm is located beside the double-bevel bulge. A free end of the elastic extension arm has an engaging part. The notches of the two clips are engaged with or disengaged from the first protruding edge and the second protruding edge, respectively.

Abstract: A linkage device cooperating with a casing, which has a connecting port, is disclosed. The linkage device includes a barrier and a push bar. The barrier is pivotly disposed on the casing and is positioned at a first position or a second position with respect to the connecting port of the casing. When the barrier is at the first position, the barrier covers at least a part of the connecting port; otherwise, when the barrier is at the second position, the barrier does not cover the connecting port. The push bar is slidingly disposed on the casing and abuts against the barrier. When the push bar pushes the barrier, the barrier rotates from the first position to the second position. A programmable control unit using the linkage device is also disclosed. The programmable control unit is assembled with a bottom board. The bottom board pushes the push bar to rotate the barrier from the first position to the second position.

Abstract: A linkage device cooperating with a casing, which has a connecting port, is disclosed. The linkage device includes a barrier and a push bar. The barrier is pivotly disposed on the casing and is positioned at a first position or a second position with respect to the connecting port of the casing. When the barrier is at the first position, the barrier covers at least a part of the connecting port; otherwise, when the barrier is at the second position, the barrier does not cover the connecting port. The push bar is slidingly disposed on the casing and abuts against the barrier. When the push bar pushes the barrier, the barrier rotates from the first position to the second position. A programmable control unit using the linkage device is also disclosed. The programmable control unit is assembled with a bottom board. The bottom board pushes the push bar to rotate the barrier from the first position to the second position.

Abstract: A quick-detachable terminal seat includes a main body and a pull rod. The terminal seat is mounted in a casing of a controller which is provided with two notches and locking slots on its periphery. The pull rod has two hooks engaged with the locking slots. The pull rod is provided with two inclined surfaces at locations corresponding to the notches respectively. When the pull rod is pulled out of the main body with the hooks being disengaged from the locking slots, the two inclined surfaces are moved out of the two notches respectively, so that the terminal seat can move upwardly with respect to the casing. In this way, the terminal seat can be detached there from quickly with less labor, or it can be mounted in the casing easily without additional tools. The present invention further provides a programmable logic controller having the terminal seat.

Abstract: A quick-detachable terminal seat includes a main body and a pull rod. The terminal seat is mounted in a casing of a controller which is provided with two notches and locking slots on its periphery. The pull rod has two hooks engaged with the locking slots. The pull rod is provided with two inclined surfaces at locations corresponding to the notches respectively. When the pull rod is pulled out of the main body with the hooks being disengaged from the locking slots, the two inclined surfaces are moved out of the two notches respectively, so that the terminal seat can move upwardly with respect to the casing. In this way, the terminal seat can be detached there from quickly with less labor, or it can be mounted in the casing easily without additional tools. The present invention further provides a programmable logic controller having the terminal seat.