Abstract: A problem determination device for a fluid device includes an object sensor for detecting an undesirable object in the fluid device and a determining section. The object sensor includes a detecting portion provided in the fluid device. The determining section determines that the fluid device has a problem when the object sensor detects an undesirable object. The problem determination device is capable of accurately determining that the fluid device has a problem at a relatively early stage of the problem.

Abstract: An improved displacement control valve incorporated in a variable displacement compressor. The control valve includes a valve body and a solenoid for actuating the valve body. The coil of the solenoid is wound about a bobbin made of insulating synthetic resin. A base plate integrally protrudes from the bobbin. A pair of conducting plates are secured to the base plate. Each plate has a clamping block. The coil has a pair of terminal wires. Each terminal wire is secured to and electrically corrected to one of the clamping blocks. Each terminal wire is wound about a holder formed in each plate between the bobbin and the corresponding clamping block. A diode is secured to the holders and is connected in parallel with the coil. A pair of terminals of the diode are secured to the corresponding holders by soldering and crimping. The holders prevent tension in the terminal wires from being applied to electrical joints formed between the wires and the clamping blocks, which makes the valve more reliable.