US 4,250,039 A · Transmission filter

Abstract

A transmission filter has a filter envelope located inside a sealed rigid container, with an intake port and a corresponding intake opening to the interior of the filter envelope located at the bottom of the container. A suction outlet port at the top of the container conveys transmission fluid passing through the filter envelope to the suction line of the transmission system. The filter envelope is formed of thermoplastic fiber felt, with two sheets or layers of the felt being ultrasonically welded to provide a continuous fluid-tight seal for the filter envelope. Ultrasonic welding of the felt is achieved by an apparatus and method that is also useful in other types of ultrasonic welding of thermoplastic fabrics. An ultrasonic horn to be vibrated at an ultrasonic frequency is provided with a knurled surface corresponding to the area to be welded. The ultrasonic horn presses a thermoplastic fabric against a stationary material to which it is to be welded, such as another sheet of the same fabric or another fabric the motion of which is limited by placing it on a knurled surface formed on a stationary plate.

Claims6

Dependent claims

A transmission filter comprising:

a rigid non-perforated container sealed to prevent direct entry of transmission fluid to the interior of said container when said container is submerged in the transmission fluid;
an intake port formed in the bottom of said container;
a suction outlet port formed in the top of said container, said container being adapted to be mounted with said suction outlet port in fluid conveying alignment with the suction line of the transmission system;
a filter envelope positioned inside said container, said filter envelope having a continuous seal to preclude passage of transmission fluid other than through the filter material itself;
an intake opening formed in said filter envelope to match said intake port to permit unfiltered transmission fluid to pass to the interior of said filter envelope only through the bottom of said container;
and
attaching means to sealingly secure said intake opening of said filter envelope in alignment with said intake port of said container to permit transmission fluid to reach the interior of said container outside said filter envelope for removal out said suction outlet port only after passing through the filter material of said filter envelope.

4 more elements

A transmission filter comprising:

a rigid metallic non-perforated container crimped about the outer edges thereof to provide a fluid-tight seal that prevents direct entry of transmission fluid to the interior of said container when said container is submerged in the transmission fluid;
a generally oblong intake port formed in the bottom of said container;
a suction outlet port formed in the top of said container, said container being adapted to be mounted with said suction outlet port in fluid conveying alignment with the suction line of the transmission system;
a first sheet of thermoplastic fiber felt having the shape of a generally triangularly shaped portion with its base along one end of a generally rectangularly shaped portion, said generally triangularly shaped portion having a rounded apex and said generally reactangularly shaped portion having one side longer than the other;
a second sheet of thermoplastic fiber felt having a generally rectangularly shaped portion corresponding to the generally rectangularly shaped portion of said first sheet and a truncated base portion of a generally triangularly shaped portion corresponding to a part adjacent the base of the generally rectangularly shaped portion of said first sheet;
a continuously sealed connecting joint formed between said sheets of thermoplastic fiber felt as the result of an ultrasonic weld between said sheets and located about the periphery of the shape defined by said second sheet to form a filter envelope, said filter envelope being located inside said container;
a generally oblong intake opening formed in said second sheet to match said intake port;
a metal eyelet crimped over the parts of said second sheet of felt and the bottom of said container about said intake opening and said intake port respectively to permit unfiltered transmission fluid to reach the interior of the filter envelope formed by the ultrasonic welding of said sheets of thermoplastic fiber felt only through the bottom of said container, the transmission fluid being filtered through said filter envelope before passing out said suction outlet port;
a generally trapezoidal opening formed in the generally triangularly shaped portion of said first sheet of fiber felt beyond where said sheets are ultrasonically welded together to permit flow of transmission fluid to said suction outlet port from either side of said filter envelope;
and
matching pear-shaped openings formed in said sheets of fiber felt to receive a mounting bolt for the filter, the portion about said pear-shaped openings being ultrasonically welded to provide a continuous seal.

8 more elements

Dependencies are inferred from the claim text.

Transmission filter

Life of this patent

Transmission filter

Life of this patent

Abstract

Claims6