Front loader washing machine with a tub with balancing weights

Abstract: The invention concerns a front-loader washing machine with a drum that is rotatably mounted in a tub, whereby balancing weights are provided on the tub at the laundry opening. Circular-arc-shaped balancing weights (40) have an essentially T-shaped cross-section, and their transverse leg (45) lies on the outside of the front (10) of the tub (20). Molded-on segments (44) that project from the transverse leg (45) are inserted and held in a form-fit receiving groove (15) open to the front and created in the front (10) of the tub (20). This allows a large door to close the laundry opening without hindering the attachment of an opening collar.

Description: The invention concerns a front-loading washing machine with a drum that is rotatably mounted in a tub, whereby the tub is provided with balancing weights at the laundry opening. A front-loader washing machine with a tub connected to balancing weights is prior art in DE OS 26 33 603. The open face of the tub is provided with an angled edge to which a bearing ring is affixed by means of a tightening band and sealing ring. The balancing weights are screwed to the bearing ring so that their outer contours do not project beyond the other contour of the tub. Given this means of fastening the balancing weights, the diameter of the laundry opening and the size of the door are limited, and it is difficult to affix the balancing weights. These disadvantages also occur when the balancing weights are fastened to the front as, for example illustrated in EP 0 318 109 A1, EP 0 601 347 A1 and EP 0 319 081 B1. The problem of the invention is to design a front-loading washing machine of the initially-cited kind so that the balancing weights can be definitely affixed to the tub and leave the face free so that this area for the larger laundry opening can be sealed with a large door. This problem is solved according to the invention in that circular-arc-shaped balancing weights have an essentially T-shaped cross-section, and a transverse leg lies on the outside of the front of the tub, and molded-on segments that project from the transverse leg are inserted and held in a form-fit receiving groove open to the front and created in the front of the tub. By designing the balancing weights in an essentially T-shape, moving them to the outside of the front of the tub, and placing a part of the balancing weights in the receiving groove that is recessed in relationship to the laundry opening allows the laundry opening to be large and makes it easy to attach a large door since it is not hindered by the balancing weights. This is an important feature for front-loading washing machines with a drum rotary axis that angles from front and back. In an advantageous embodiment, two identical balancing weights are affixed diametrically opposed to the front of the tub, the balancing weights extend over less than 180° of the perimeter of the front, projecting mounting flanges are affixed to both ends and the middle of the balancing weights, and the balancing weights are made of concrete into which the mounting flanges are cast. The balancing weights can be affixed to the tub in a manner such that the receiving groove in the front of the tub forms a transitional wall to the drum bearing to which are attached (preferably molded on) radial sections of C-shaped mounting bars, and nuts for screw connections are placed in the mounting bar sections that can be used to screw the mounting flanges of the balancing weights to the mounting bars. The six mounting bar sections can be distributed at 60° intervals so that the mounting flanges of the balancing weights in the same section permit the balancing weights to be arranged in a diametrically opposed manner. The mounting flanges of the balancing weights must be in the same plane, and the middle mounting flanges project on the concave sides of the transverse legs of the circular-arc-shaped balancing weights so that the balancing weights can be correctly positioned. The method of the fixing the balancing weights to the front of the tub can be improved in that the end section of the front of the tub forms a receiving groove open to the outside in which the segments projecting on the concave inside of the balancing weights are inserted in a form-fit and held. In addition, the thickness of the transverse legs can be reduced with the provided weight. The face of the end section of the front of the tub remains free and can be used for affixing the door and the opening collar. The end section of the front of the tub and the balancing weights are harmonised with each other so that the outer contour of the balancing weights connected to the end section of the front of the tub does not project beyond the outer contour of the tub and unnecessarily restrict the oscillation of the tub in relation to the machine housing. The invention will be further explained with reference to an exemplary embodiment shown in the drawing. Shown are: Fig. 1 a perspective front view of a tub with an affixed opening collar and two identical balancing weights in their mounted position, Fig. 2 a partial cross-section of the front of the tub with diametrically opposed balancing weights on the end section, and Fig. 3 another partial cross-section of the front of the tub that shows the T-shaped balancing weights in their affixed position. Fig. 1 shows an exemplary embodiment of the tub 20 that has a separate front 10. At least the front 10 is designed and manufactured as a plastic injection-molded part. At the laundry opening 15, the front 10 transitions into an end section 13 with a smaller diameter. The transition 12 is perpendicular to the mid-axis of the tub 20. At the free face of the end section 13, a large door and an opening collar 30 can be affixed without being restricted as shown in the partial cross-section in Fig. 2. Molded as a single piece onto the transitional wall 12 of the front 10 that forms a part of the created receiving groove 14 are radial mounting bar sections 11 that have a T-shaped recess for nuts open to the loading side. The mounting bar sections 11 can be distributed at e.g. 60° intervals when the balancing weights 40 have three mounting flanges 41, 42 and 43 that are affixed (e.g. cast) in a projecting manner to the balancing weights 40 with the same distribution. The mounting flanges 41 and 42 project on the ends of the circular-arc-shaped balancing weights 40. The middle mounting flange 43 on the concave side is radially aligned on the balancing weight 40 to maintain the 60° distribution. All mounting flanges 41, 42 and 43 are in the same plane so that the two identical balancing weights 40 can be in the correct position diametrically opposed to each other screwed to the mounting bar sections 11 of the transitional wall 12. As can be seen in Fig. 2, screw connections 50 are used that consist of a fixing screw that fits in a hole in the mounting flanges 41, 42, and 43, and a nut inserted in the mounting bar sections 11. The balancing weights 40 are made of concrete with cast mounting flanges 41, 42 and 43. Their weight is sufficient, and they are easy and economical to manufacture. The tub 20 with the drum in the machine housing and the pivot bearing and drive for the drum in the tub 20 can be attached in a conventional matter since this does not impair fastening the balancing weights 40 to the front 10 of the tub 20. The section in Fig. 3 shows a cross-section of the circular-arc-shaped balancing weights 40. The transverse legs 45 lie on the outside of the front 10 and are inserted in a form-fit together with the inwardly-projecting segments 44 into the receiving groove 14 of the end section 13 of the front 10. The transverse legs 45 of the balancing weights 40 do not project beyond the outer contour of the tub 20, and their distance from the machine housing is sufficient for the arising oscillations. The segments 44 in the receiving groove 14 allow the thickness of the transverse legs 45 to be small with the balancing weights 40 at the provided weight. The unit consisting of the tub 20 and drum do not take up more room in the machine housing, yet there is more room to attach the door and opening collar 30. The door can be larger which is advantageous when installing the drum and tub with a mid-axis that drops from the front and back that is hence the rotary axis of the drum.

Claims: A front-loader washing machine with a drum that is rotatably mounted in a tub (20), whereby balancing weights (40) are provided at the laundry opening on the tub, characterised in that circular-arc-shaped balancing weights (40) have an essentially T-shaped cross-section, and their transverse leg (45) lies on the outside of the front (10) of the tub (20), and molded-on segments (44) that project from the transverse leg (45) are inserted and held in a form-fit receiving groove (14) open to the front that is created in the front (10) of the tub (20). A front-loader washing machine according to claim 1, characterised in that two identical balancing weights (40) are affixed diametrically opposed to the front (10) of the tub; the balancing weights (40) extend over less than 180° of the perimeter of the front (10), and projecting mounting flanges (41,42,43) are affixed to both ends and the middle of the balancing weights (40). A front-loader washing machine according to claims 1 or 2, characterised in that the balancing weights (40) are made of concrete into which the mounting flanges (41,42,43) are cast. A front-loader washing machine according to one of claims 1 - 3, characterised in that the receiving groove (14) in the front (10) of the tub (20) forms a transitional wall (12) to the drum bearing to which are attached, preferably molded on, radial sections of C-shaped mounting bars (11), and nuts for screw connections (50) are placed in the mounting bar sections (11) that can be used to screw the mounting flanges (41,42,43) of the balancing weights (40) to the mounting bars (11). A front-loader washing machine according to claim 4, characterised in that the mounting flanges (41,42,43) of the balancing weights (40) are in the same plane. A front-loader washing machine according to one of claims 1 - 5, characterised in that at least the front (10) of the tub (20) is designed as a plastic injection-molded part. A front-loader washing machine according to one of claims 1 - 6, characterised in that the end section (13) of the front (10) of the tub (20) is connected to an opening collar (30). A front-loader washing machine according to one of claims 1 - 7, characterised in that the transverse legs (45) of the balancing weights (40) connected to the end section (13) of the front (10) of the tub (20) do not project beyond the outer contour of the tub.

Inventors: NICOLOSI VINCENZO, TALAL SAID, NICOLOSI, VINCENZO, TALAL, SAID
Applicants: WHIRLPOOL CO, WHIRLPOOL CORPORATION
Application year: 2001
Main classification: D06F37
IPC codes: D06F37