Throttle apparatus for engine

A throttle apparatus for an engine, comprising:

• a pair of throttle bodies disposed side by side in an arrangement direction of a pair of banks constituting a V-type engine, between the banks;
• a pair of throttle bores provided in the respective throttle bodies, and configured to guide intake air into cylinders of the pair of banks;
• a pair of throttle valves supported to be openable/closable inside the respective throttle bores, by a pair of throttle shafts, the pair of throttle shafts each intersecting the arrangement direction of the banks and an axial direction of the throttle bores and being parallel to each other;
• a pair of coupling portions provided integrally with the respective throttle bodies and extending in a direction approaching each other, and configured to couple the pair of throttle bodies by being fastened at abutting portions superimposed on each other with fastening members, wherein
• one of the pair of throttle bodies is a main throttle body having, as a driving protrusion end, one end of one corresponding of the throttle shafts protruding outside, and
• the other of the pair of throttle bodies is a sub-throttle body having, as a driven protrusion end, one end of the other of the throttle shafts protruding outside;
• a motor unit, which is connected to the other end of the throttle shaft of the main throttle body, and opens/closes the throttle valve through the throttle shaft by using a motor as a driving source;
• an interlocking mechanism, which is provided between the driving protrusion end and the driven protrusion end, and transmits turning of the driving protrusion end to the driven protrusion end;
• and
• a motor housing chamber, which houses the motor, is integrally formed with the main throttle body, wherein
• base portions of the coupling portions extend from two positions that are separated in the right-left direction on an outer peripheral surface of the motor housing chamber, each of the respective base portions provided with a rib having a triangular shape in which a vertical width is gradually reduced from the motor housing chamber thereby providing each of the coupling portions with a tapered shape.