Filling machine for food products in cans, particularly of the type with product density control

A filling machine for food products in cans, particularly of the type with product density control, comprising a supporting frame which forms a chamber and a feeding tunnel which is adapted to convey a food product into said chamber;

• said chamber being provided with a plunger which can move along said chamber, along a predefined compression direction, between a bottom dead center position (PMI), in which said chamber is free from said plunger in order to feed said food product into said chamber, and a top dead center position (PMS), in which said plunger occupies at least partially said chamber for a compression of said food product into at least one preset shape;
• said chamber being provided with at least one expulsion piston which is configured to move transversely with respect to said compression direction for an expulsion of said at least one preset shape in a direction of a station for canning said food product;
• motor means being further provided which are associated with said plunger for a movement thereof along said compression direction;
• and further comprising means for measuring a density of said food product compressed in said chamber in order to control a driving torque of said motor means as a function of an achievement of a predetermined density value.

A method for the filling of food products in metallic boxes, cans, comprising the steps of:

• feeding a food product to a chamber provided with a plunger which is configured to move along said chamber, along a predefined compression direction, between a bottom dead center position (PMI), in which said chamber is free from said plunger in order to feed said food product into said chamber, and a top dead center position (PMS), in which said plunger occupies at least partially said chamber for a compression of said food product into at least one preset shape;
• setting up a predetermined density value of said food product;
• compressing said food product by means of said plunger;
• measuring a density of said food product compressed by said plunger in said chamber;
• actively controlling, during the compression of each single compression cycle, a driving torque of the motor means adapted to move said plunger, said driving torque being controlled by detecting a density of the food product compressed and adjusting said driving torque in order to achieve said predetermined density value of said food product;
• upon achieving said predetermined density value of said food product stopping a stroke of said piston in a position that corresponds to said predetermined density value, avoiding compressing further said food product.