Filter apparatus having filter elements shiftable between filtering and backwashing positions

A filter apparatus for cleaning thermoplastic material comprising:

• a housing;
• means for forming an inlet passage in the housing for receiving material to be filtered;
• means for forming an outlet passage in the housing for discharging filtered material;
• at least two carrier members, each carrier member carrying a sieve means having an inlet side and an outlet side;
• means for forming a rinsing passage for each sieve means, each rinsing passage being disposed within an associated carrier member and being in fluid communication with the outlet side of its associated sieve means;
• means for slidably guiding the carrier members within the housing;
• and
• means for shifting each carrier member between an operating position and a rinsing position;
• wherein the inlet side of a sieve means is in fluid communication with the inlet passage and the outlet side of the sieve means is in fluid communication with the outlet passage for flowing material to be filtered from the inlet side to the outlet side of the sieve means when the carrier member associated with the sieve means is in the operating position;
• and
• wherein the rinsing passage is in fluid communication with the outlet passage for flowing filtered material from the outlet side of the sieve means toward teh inlet side of the sieve means when the carrier member associated with the sieve means is in the rinsing position.

A filter apparatus for cleaning thermoplastic material comprising:

• a housing;
• means for forming an inlet passage in the housing for receiving material to be filtered;
• means for forming an outlet passage in the housing for discharging filtered material;
• at least two carrier members, each carrier member removably carrying a sieve means having an inlet side and an outlet side;
• means for forming a rinsing passage for each sieve means, each rinsing passage being disposed within an associated carrier member and being in fluid communication with the outlet side of its associated sieve means;
• means for slidably guiding the carrier members within the housing;
• means for shifting each carrier member between an operating position and a rinsing position;
• and
• means for shifting each carrier member beyond the rinsing position so that the sieve means is disposed entirely outside of the housing;
• wherein the inlet side of a sieve means is in fluid communication with the inlet passage and the outlet side of the sieve means is in fluid communication with the outlet passage for flowing material to be filtered from the inlet side to the outlet side of the sieve means when the carrier member associated with the sieve means is in the operating position;
• wherein the rinsing passage is in fluid communication with the outlet passage for flowing filtered material from the outlet side of the sieve means toward the inlet side of the sieve means when the carrier member associated with the sieve means is in the rinsing position;
• and
• wherein the sieve means may be removed from its associated carrier member when the carrier member is beyond the rinsing position.