Driver for fastening to a sheet metal drum of a laundry machine
View Patent ↗Fastening plastic drivers in a washing machine drum having at least two domes on the inside, which comprise a cavity extending along its center line, and are oriented perpendicular to the sheet casing of the drum and which serve to fasten the driver. A hole pattern corresponding to the arrangement of the domes of a driver is punched into the sheet casing of the drum. The driver is placed with its dome ends, which project beyond the contact surface of the driver with the sheet casing, onto the sheet casing so that the dome ends pass through the holes of the hole pattern. Counter holders are inserted from the opposite side into the cavities of the domes. From the fastening side, hold-down elements are driven against the sheet casing. Heated form punches are driven against the dome ends until the dome ends have mushroom-shape ends.
1. A driver for fastening to a sheet casing of a drum of a laundry machine, the driver comprising:
an outside surface that is configured to contact laundry in the drum;
an edge that is configured to contact the sheet casing when the driver is fastened to the sheet casing;
an inside that is opposite to the outside surface, and faces the sheet casing and is enclosed by the sheet casing when the driver is fastened to the sheet casing;
at least two domes on the inside and extending away from the outside surface, each dome being oriented such that it will be perpendicular to the sheet casing when fastened to the sheet casing;
a solid portion at the end of each dome; and
a cavity in each dome that extends along the centre line of the dome, the cavity stopping at the solid portion,
wherein each dome is configured to being inserted into a hole in the sheet casing such that a deforming portion of the solid portion of each dome extends beyond the sheet casing,
each cavity is configured to receive a counter holder during a fastening process such that the counter holder supports the dome during the fastening process; and
the deforming portion is configured to deform during the fastening process by being heated and molded by a form punch until the deforming portion deforms into a mushroom-shaped end which rest against the sheet casing in an area around the hole.
2. The driver according to claim 1 , wherein the deforming portion is configured to deform during the fastening process by the form punch while the form punch is heated.
3. The driver according to claim 1 , wherein the deforming portion is configured to deform during the fastening process by the form punch while the form punch is vibrating ultrasonically after driving down onto the plastic dome ends and the vibrations are transmitted to the plastic dome ends, whereby the plastic dome ends are heated.
4. The driver according to claim 1 , wherein each dome has surrounding supporting walls which extend as far as the inner surface of the sheet casing, and a gap exists between each supporting wall and the dome at a point on the dome where the dome is configured to pass through the hole in the sheet casing, the gaps being configured to receive the sheet casing as the sheet casing is deformed into the gaps as the mushroom-shaped ends are formed.
5. The driver according to claim 1 , wherein each dome has an overall longitudinal dimension perpendicular to the sheet casing and an overall transverse dimension parallel to the sheet casing, and the longitudinal dimension is larger than the transverse dimension.