Housing Main Part of a Filter Housing, Filter System, and Pre-Separator Module of a Filter System

A housing main part of a filter housing of a filter system, the housing main part comprising:

• circumferential walls defining an interior comprising an element receiving space and an adapter chamber;
• at least one outlet communicating with the interior, wherein a fluid to be filtered passes though the interior along a main flow axis from an inlet side of the housing main part to the at least one outlet;
• at least one mounting opening arranged laterally on the housing main part relative to the main flow axis and configured to be closed by a housing cover, the at least one mounting opening configured to enable insertion of at least one exchangeable filter element into the element receiving space or removal of the at least one exchangeable filter element from the element receiving space;
• the housing main part configured to receive at least one pre-separator module, wherein the at least one pre-separator module and the at least one exchangeable filter element are arranged behind each other along the main flow axis such that the at least one outlet and an inlet of the filter housing are separated from each other, wherein the inlet of the filter housing is at least partially formed by the at least one pre-separator module;
• wherein the adapter chamber is arranged at an axial end face of the housing main part axially arranged relative to the main flow axis, wherein the adapter chamber, relative to the main flow axis, is open axially toward the element receiving space and, axially opposed thereto, toward an environment;
• wherein the adapter chamber is configured to accommodate at least partially the least one pre-separator module;
• the at least one exchangeable filter element;
• or the least one pre-separator module and the at least one exchangeable filter element;
• wherein the at least one mounting opening is surrounded by at least one cover receiving rim that extends across at least a portion of the adapter chamber;
• wherein the housing main part comprises at or within the adapter chamber at least one part of a connecting device configured to connect the at least one pre-separator module to the housing main part.