Abstract: An object is to effectively cool down an electronic equipment which is face with height limitations and tends to readily increase in heat generation amount to thereby provide the reliability required. The interior of a chassis of a control unit is partitioned by a back board into a front side space and a rear side space. In the rear side space, two control modules are attached so that these are stacked up and down, while two fan modules and a single duct member are attached in the front side space. Each fan module has two fans as built therein. A cooling air stream or “wind” from each fan flows into the lower-side control module through the duct member and others, whereas a cooling wind from the other fan flows into the upper-side control module. Even when either one of the fan modules goes down during operation, it is still possible by using the remaining fan module to cool down the both control modules.

Abstract: An object is to effectively cool down an electronic equipment which is face with height limitations and tends to readily increase in heat generation amount to thereby provide the reliability required. The interior of a chassis of a control unit is partitioned by a back board into a front side space and a rear side space. In the rear side space, two control modules are attached so that these are stacked up and down, while two fan modules and a single duct member are attached in the front side space. Each fan module has two fans as built therein. A cooling air stream or “wind” from each fan flows into the lower-side control module through the duct member and others, where as a cooling wind from the other fan flows into the upper-side control module. Even when either one of the fan modules goes down during operation, it is still possible by using the remaining fan module to cool down the both control modules.