GB2053286A - Batch washing machine - Google Patents

Abstract

In a batch washing machine comprising a tubular washing drum with a helically coiled wall member extending along the inside of the drum to act as a screw conveyor and at the same time to form successive washing chambers for the batches of laundry, the said wall comprises successive wall portions 5a, 5b, with stepwise transitions. Thus the wall acts like a washboard and improves the mechanical contribution to the washing effect due to reciprocating rotary movement of the wall about the axis of the drum. Conveniently, the wall consists of triangular wall portions 5a, 5b arranged as shown in the drawing, preferably about 12 pairs of wall portions to one helical turn of the wall. The wall can readily be made up of halfturns welded together, the triangular wall portions being preferably so shaped as to provide a common side edge 6 of each pair of adjacently disposed portions which extends radially with respect to the axis of rotation. <IMAGE>

Description

SPECIFICATION Batch washing machine The invention relates to a batch washing machine having a tubular washing drum with a built-in helically coiled wall acting as a screw conveyor.

In known batch washing machines of this type (German Utility Model Specification 1,894,718) the individual laundry batches are introduced at one end of the washing drum and taken out at the other end. Each turn of the screw conveyor forms a chamber for one laundry batch. The actual washing operation is effected by reciprocating rotary movement of the washing drum through less than 3600, whereas the transporting of the laundry from chamber to chamber is effected by one revolution of the drum in each case. In addition to the means for transporting the laundry, arrangements have also been made for introducing and discharging the washing water, rinsing water and washing agents and for heating, since not only the mechanical influence but also the temperature and the chemical effects are important to the washing action.

The present invention has as its object to improve the mechanical contribution to the washing effect in washing machines of the type specified, since it is least harmful to the laundry and involves less expense.

According to the present invention this is achieved with the measures proposed in the appended claims.

Because of the stepped transitions between the individual wall portions in the helically wound wall bounding the washing chambers, this wall acts like a washboard. With the reciprocating motion of the washing drum the laundry is more easily carried along on the steps, and its component articles moved more intensively relatively to one another on subsequently sliding down. In addition, a screw conveyor of this kind can be produced at small cost, since a helical turn can be obtained simply by bending the wall portions, and a plurality of wall portions can be welded together to constitute a screw conveyor in a simple manner.

A constructional example is shown in the drawings wherein: Fig. 1 shows a length of drum in fragmentary manner; Fig. 2 shows a turn of the helical wall in perspective.

A helically coiled wall 2 is securely welded in the tubular washing drum 1. The wall 2 divides the washing drum 1 into individual chambers 3. When the washing drum is given a reciprocating rotary movement a batch of laundry 4 is moved with a rocking action to and fro within a chamber 3. The mechanical influence which this exerts on the laundry is of decisive importance for the washing effect.

As can be seen from Fig. 2, the wall 2 is made up of triangular wall portions 5a and 5b. The bases of the smaller wall portions 5b form the inner periphery, and the bases of the larger wall portions 5a the outer periphery of the wall 2, since apexes and bases of two adjacently disposed wall portions 5a and 5b are arranged in opposite directions from the one triangle to the other. The smaller wall portion 5b is slightly angled relatively to the larger wall portion 5a. In this way a stepped transition is obtained, and at the same time the extent of the angle of setting gives the desired pitch for the helically coiled wall and thus the width of a chamber 3.

Thus it is possible in a simple way to vary the wall 2 without having to carry out complicated conversion operations.

The step is broadest in the region of lower circumferential speed, which has an equalising effect on the mechanical washing action between inner and outer peripheries, and promotes movement of the batches of laundry.

Because the triangular wall portions are so arranged with regard to the axis of rotation that a common side edge 6 of each two adjacently disposed wall portions extends radially with respect to the axis of rotation, the joining together of several part-turns to form the complete screw conveyor is made easier. It has been found useful to have a turn of the wall 2 formed of about 12 pairs of wall portions, each half-turn being first produced from 6 pairs of wall portions and then these halves being welded together.

1. Batch washing machine comprising a tubular washing drum which is provided, to act as a screw conveyor, with a helically coiled wall which at the same time serves to form the washing chambers, wherein the helically coiled wall comprises successive wall portions with stepwise transitions.

2. Batch washing machine according to claim 1, wherein the said wall consists of triangular wall portions, the wall portions being situated in each case with an apex and a base adjacent to one another at the inner edge of the wall and likewise at the outer edge.

3. Batch washing machine according to claim 1 or 2, wherein a common side edge of each two adjacent triangular wall portions is situated radially.

4. Batch washing machine according to any one of claims 1 to 3, wherein 12 pairs of wall portions are provided over the extent of one turn of the wall.

5. A batch washing machine substantially as herein described with reference to the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (5)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Batch washing machine The invention relates to a batch washing machine having a tubular washing drum with a built-in helically coiled wall acting as a screw conveyor. In known batch washing machines of this type (German Utility Model Specification 1,894,718) the individual laundry batches are introduced at one end of the washing drum and taken out at the other end. Each turn of the screw conveyor forms a chamber for one laundry batch. The actual washing operation is effected by reciprocating rotary movement of the washing drum through less than 3600, whereas the transporting of the laundry from chamber to chamber is effected by one revolution of the drum in each case. In addition to the means for transporting the laundry, arrangements have also been made for introducing and discharging the washing water, rinsing water and washing agents and for heating, since not only the mechanical influence but also the temperature and the chemical effects are important to the washing action. The present invention has as its object to improve the mechanical contribution to the washing effect in washing machines of the type specified, since it is least harmful to the laundry and involves less expense. According to the present invention this is achieved with the measures proposed in the appended claims. Because of the stepped transitions between the individual wall portions in the helically wound wall bounding the washing chambers, this wall acts like a washboard. With the reciprocating motion of the washing drum the laundry is more easily carried along on the steps, and its component articles moved more intensively relatively to one another on subsequently sliding down. In addition, a screw conveyor of this kind can be produced at small cost, since a helical turn can be obtained simply by bending the wall portions, and a plurality of wall portions can be welded together to constitute a screw conveyor in a simple manner. A constructional example is shown in the drawings wherein: Fig. 1 shows a length of drum in fragmentary manner; Fig. 2 shows a turn of the helical wall in perspective. A helically coiled wall 2 is securely welded in the tubular washing drum 1. The wall 2 divides the washing drum 1 into individual chambers 3. When the washing drum is given a reciprocating rotary movement a batch of laundry 4 is moved with a rocking action to and fro within a chamber 3. The mechanical influence which this exerts on the laundry is of decisive importance for the washing effect. As can be seen from Fig. 2, the wall 2 is made up of triangular wall portions 5a and 5b. The bases of the smaller wall portions 5b form the inner periphery, and the bases of the larger wall portions 5a the outer periphery of the wall 2, since apexes and bases of two adjacently disposed wall portions 5a and 5b are arranged in opposite directions from the one triangle to the other. The smaller wall portion 5b is slightly angled relatively to the larger wall portion 5a. In this way a stepped transition is obtained, and at the same time the extent of the angle of setting gives the desired pitch for the helically coiled wall and thus the width of a chamber 3. Thus it is possible in a simple way to vary the wall 2 without having to carry out complicated conversion operations. The step is broadest in the region of lower circumferential speed, which has an equalising effect on the mechanical washing action between inner and outer peripheries, and promotes movement of the batches of laundry. Because the triangular wall portions are so arranged with regard to the axis of rotation that a common side edge 6 of each two adjacently disposed wall portions extends radially with respect to the axis of rotation, the joining together of several part-turns to form the complete screw conveyor is made easier. It has been found useful to have a turn of the wall 2 formed of about 12 pairs of wall portions, each half-turn being first produced from 6 pairs of wall portions and then these halves being welded together. CLAIMS

1. Batch washing machine comprising a tubular washing drum which is provided, to act as a screw conveyor, with a helically coiled wall which at the same time serves to form the washing chambers, wherein the helically coiled wall comprises successive wall portions with stepwise transitions.

2. Batch washing machine according to claim 1, wherein the said wall consists of triangular wall portions, the wall portions being situated in each case with an apex and a base adjacent to one another at the inner edge of the wall and likewise at the outer edge.

3. Batch washing machine according to claim 1 or 2, wherein a common side edge of each two adjacent triangular wall portions is situated radially.

4. Batch washing machine according to any one of claims 1 to 3, wherein 12 pairs of wall portions are provided over the extent of one turn of the wall.

5. A batch washing machine substantially as herein described with reference to the accompanying drawings.