A packer machine to produce a pack; the packer machine comprises: a protection case; a wrapping line, which is provided with a plurality of movable wrapping devices; at least one first actuator, which is designed to cause the movable wrapping devices to move; an insertion station (S 1), which is arranged along the wrapping line and where the wrapping line receives one single wrapping material to be folded; an input station, which is separate from the wrapping line and has a loading opening obtained in the protection case; a transfer unit, which is designed to receive wrapping material groups in the input station and to direct the wrapping material towards the wrapping line; and at least one second actuator, which is independent of the first actuator and is designed to move the transfer unit; wherein the protection case encloses the input station, i.e. prevents the direct access from the outside to the input station; the packer machine is characterized in that it comprises: a sensor device, which is designed to detect the presence of a body in the loading opening of the input station; and a control unit, which is configured to stop, when the packer machine is working, the sole second actuator, thus allowing the first actuator to normally operate, if the sensor device detects the presence of a body in the loading opening and to automatically restart the second actuator if the sensor device stops detecting the presence of a body in the loading opening. a protection case; a wrapping line, which is provided with a plurality of movable wrapping devices; at least one first actuator, which is designed to cause the movable wrapping devices to move; an insertion station (S 1), which is arranged along the wrapping line and where the wrapping line receives one single wrapping material to be folded; an input station, which is separate from the wrapping line and has a loading opening obtained in the protection case; a transfer unit, which is designed to receive wrapping material groups in the input station and to direct the wrapping material towards the wrapping line; and at least one second actuator, which is independent of the first actuator and is designed to move the transfer unit; wherein the protection case encloses the input station, i.e. prevents the direct access from the outside to the input station; the packer machine is characterized in that it comprises: a sensor device, which is designed to detect the presence of a body in the loading opening of the input station; and a control unit, which is configured to stop, when the packer machine is working, the sole second actuator, thus allowing the first actuator to normally operate, if the sensor device detects the presence of a body in the loading opening and to automatically restart the second actuator if the sensor device stops detecting the presence of a body in the loading opening. a sensor device, which is designed to detect the presence of a body in the loading opening of the input station; and a control unit, which is configured to stop, when the packer machine is working, the sole second actuator, thus allowing the first actuator to normally operate, if the sensor device detects the presence of a body in the loading opening and to automatically restart the second actuator if the sensor device stops detecting the presence of a body in the loading opening.