EP0080719B1

EP0080719B1 - A bale press and method for compressing waste material into bales

Info

Publication number: EP0080719B1
Application number: EP82110989A
Authority: EP
Inventors: John Per Evert Nilsson
Original assignee: PERSONER VERKSTAD AB
Current assignee: PERSONER VERKSTAD AB
Priority date: 1981-11-30
Filing date: 1982-11-27
Publication date: 1988-07-27
Also published as: ATE35940T1; EP0080719A3; DE3278809D1; SE8107127L; SE432905B; EP0080719A2

Abstract

A hydraulic bale press and a method for compressing bulky goods into bales. The bale press comprises an inlet section (2), a prepress chamber (3) and a main press chamber (4). The prepress chamber (3) comprises a prepress (7) having a prepress unit (8) arranged on a carriage (11) and pivotable around an axis (9). The carriage is reciprocable between a retracted position leaving the prepress chamber (3) essentially free, and an extended position in which a first precompression takes place. A second precompression is made by pivoting the prepress unit (8) around the axis (9) to the position shown in broken lines, thereby compressing the goods down into the main press chamber. During the two steps of the precompression, goods are continuously infed. After performing one or several precompression operations, a main compression is made by means of a main compression plunger (16), thereby feeding the material into a baling channel (18), where the bale is formed and treated in a conventional way.

Description

Field of Invention

The present invention relates to a bale press and a method for compressing waste material into bales, e.g. return paper, cardboard boxes or similar bulky goods.

Prior Art

A previously known bale press comprises a prepress and a main press. An inlet opening opens into a prepress chamber. When this chamber is filled, a precompressing of the goods takes place into a main press chamber. The filling and precompressing can be repeated until sufficient material has been precompressed into the main press chamber. At this stage, the prepress stops in its bottom position and the main press is activated for compressing the material into a bale, which is expelled through a channel, whereupon a new filling, precompressing and maincompres- sing takes place until a predetermined bale length has been achieved, whereupon baling takes place. The bales are successively fed out from the channel.
Such a previously known bale is shown in US-A-4 121 515 which disclosed an apparatus for baling unshredded material comprising: a charging inlet for receiving loose material; a baling chamber into which material is delivered from said inlet; a discharge outlet from said bailing chamber; a first reciprocal baling head adapted to move toward and away from a fixed sidewall between a retracted position for receiving loose material through said inlet and an advanced position spaced from said fixed sidewall; means for reciprocating said first baling head for precompression; a second reciprocable baling head adapted to move in a direction generally perpendicular to the direction of movement of said first baling head between a retracted position for receiving loose material and an advanced position for compacting material into said outlet; and means for reciprocating said second baling head for main compression.
Another such a previously known bale press is shown in GB-A-1 360 215, which discloses a bale press having precompaction and main compression. When a precompaction chamber is filled with material to be baled, two lid plates are swung from an open position to a closed position for defining a baling chamber.
Bale presses without any prepress do also exist.
In some applications it is desirable to have a wider inlet opening in order to be able to accommodate larger empty boxes and similar. If the above-mentioned bale press was constructed having a wider inlet opening, at least the prepress would have to be proportionally enlarged and the total bale press would be too bulky for many applications. The other way round, the present bale press is already too big for certain applications, and thus there is a need for a small but efficient bale press.

Disclosure of the invention

The object of the present invention is to provide a bale press of the type disclosed in US-A-4121 515 where it is possible to use a wider inlet opening or alternatively the machine size can be diminished.
Thus, in the practice of the invention, the precompression takes place in two steps, a first precompression in the horizontal direction and a subsequent precompression down into the main press chamber. After the first precompression, further material can be loaded before the second precompression takes place down into the main chamber.
According to a first aspect of the invention, there is provided a bale press for compressing bulky goods into bales, comprising an inlet section, a prepress chamber and a main press chamber, whereby a main press plunger is adapted to perform a main compression of the goods into a bale, wherein the prepress chamber contains a prepress unit with at least one forward wall reciprocable between a retracted position essentially leaving the prepress chamber free and an extended position in which the forward wall substantially decreases the volume of the prepress chamber, characterised in that the prepress unit is quadrantal in cross-section and is pivotable around an axis positioned on a carriage between a first position in which the forward wall of the prepress unit is essentially vertical, to a second position in which the forward wall of the prepress unit is essentially horizontal in order to provide a second precompression of the goods from the prepress chamber to the main press chamber.
Preferably, the movements of the bale press are imparted by means of hydraulic cylinder units, and the carriage is guided on horizontal rails.
There is also provided, according to a second aspect of the invention, a method of compressing bulky goods into bales in a bale press comprising an inlet section, a prepress chamber and a main press chamber, including the step of compressing the goods in the main compression chamber into a bale by means of a main press plunger, a first precompression by reciprocating a prepress unit having at least one forward wall, from a retracted position to an extended position in which the forward wall substantially decreases the volume of the prepress chamber, characterised by pivoting the prepress unit, which is quadrantal in cross-section and is pivotable around an axis positioned on a carriage, from a first position in which the forward wall is essentially vertical, to a second position in which the forward wall is essentially horizontal thereby providing a second precompression of the goods from the prepress chamber to the main press chamber.

Brief description of the drawings

Further objects of the invention will appear at the detailed description below of a preferred embodiment of the invention by reference to the drawings. Fig. 1 is a longitudinal side view with the side plate removed of the bale press according to the invention in the start position or load position, and Fig. 2 is a similar side view of the bale press according to Fig. 1 after the horizontal compress operation.

Detailed description of the preferred embodiment

The bale press is shown in a longitudinal side view in Fig. 1 with the side plate removed. The bale press comprises an inlet section 2, a prepress chamber 3 and a main press chamber 4. The inlet section 2 is intended to be loaded from above.
Beside the prepress chamber 3 there is a prepress 7, comprising a prepress unit 8 being quadrantal in cross-section and having a fore- ward wall 19, which at its lower perpendicular side is pivotably journalled on an axis 9 and is driven by a cylinder unit 10. The complete prepress unit 8 is arranged on a carriage 11, which is horizontally reciprocable along a guiding or rails 12 between a retracted position shown in Fig. 1 and an extended position shown in Fig. 2 by means of a cylinder unit 13. During the horizontal movement, the volume of the prepress chamber 3 is decreased and a precompression takes place in a first step. Simultaneously with this horizontal movement of the carriage, an upper plate 14 follows the movement of the carriage and prevents goods to fall down behind the carriage 11.
After the first compression, a second compression takes place in a second step, by pivoting the prepress unit 8 around the axis 9 to the position shown in broken lines in Fig. 2, thereby precompressing the material in the prepress chamber 3 down into the main press chamber 4 by the forward wall 19. During this pivoting movement, the plate 14 prevents the goods to fall down behind the back rim of the prepress unit 8.
Thereafter, the prepress unit 8 is repivoted and the carriage is retracted to the position shown in Fig. 1, and a continued filling of goods takes place, followed by a precompression as stated above. When the main press chamber 4 is full, a main compression takes place by means of the plunger 16, which is driven by a cylinder unit 17 and the bale is pressed into a channel 18, of which only the entry is shown on the drawings. The continued baling operation is in accordance with known technique and is thus not given in detail here.
Experiments have proven that the addition of said horizontal precompression step at certain troublesome materials gives a firm and stable completed bale, where previously problems have been encountered since the bale was too softly crammed. This is specially true for big cardboard boxes having relatively loose walls.
The method described above is used when the compression of bulky goods takes place. When heavy goods are compressed, such as periodicals, this is done with the carriage in the position shown in Fig. 2 and the plates 5 are unfolded. Moreover, a material distributor 6 is unfolded and activated, which rotates and distributes and partially disintegrates the goods. Thereafter, a precompression is made by pivoting the prepress unit 8 forwards and downwards, one or several times and finally a main compression is made.
The inlet opening can now be made about double as wide as previously which entails an increased capacity. During the precompression normally a continuous goods infeed takes place, but it is also possible to stop the infeed during the compression operation.
The increased efficiency can also be used for making the machine considerably smaller.
In the above a preferred embodiment of the invention has been described in order to eludicate the invention. However, the invention is not limited to the embodiment shown but can be modified in many respects within the scope of the invention, as defined in the appended claims.

Claims

1. A bale press for compressing bulky goods into bales, comprising an inlet section (2), a prepress chamber (3) and a main press chamber (4), whereby a main press plunger (16) is adapted to perform a main compression of the goods into a bale, wherein the prepress chamber contains a prepress unit (8) with at least one forward wall (19) reciprocable between a retracted position essentially leaving the prepress chamber (3) free and an extended position in which the forward wall (19) substantially decreases the volume of the prepress chamber, characterised in that the prepress unit (8) is quadrantal in cross-section and is pivotable around an axis (9) positioned on a carriage (11) between a first position in which the forward wall (19) of the prepress unit is essentially vertical, to a second position in which the forward wall (19) of the prepress unit is essentially horizontal in order to provide a second precompression of the goods from the prepress chamber (3) to the main press chamber.

2. A bale press according to claim 1, characterized in that the movements of the bale press are imparted by means of hydraulic cylinder units (10, 13, 17).

3. A bale press according to claim 1 or 2, characterized in that the carriage is guided on horizontal rails (12).

4. A method of compressing bulky goods into bales in a bale press comprising an inlet section (2), a prepress chamber (3) and a main press chamber (4), including the step of compressing the goods in the main compression chamber into a bale by means of a main press plunger (16), a first precompression by reciprocating a prepress unit (8) having at least one forward wall (19), from a retracted position to an extended position in which the forward wall substantially decreases the volume of the prepress chamber, characterized by pivoting the prepress unit (8), which is quadrantal in cross-section and is pivotable around an axis (9) positioned on a carriage (11), from a first position in which the forward wall (19) is essentially vertical, to a second position in which the forward wall is essentially horizontal thereby providing a second precompression of the goods from the prepress chamber to the main press chamber.