EP0058449A1

EP0058449A1 - Bale press

Info

Publication number: EP0058449A1
Application number: EP82200127A
Authority: EP
Inventors: Karl Heinz Denneboom; Antonius Lambertus Gerardus Mensink
Original assignee: Machinefabriek Boa BV
Current assignee: Machinefabriek Boa BV
Priority date: 1981-02-13
Filing date: 1982-01-29
Publication date: 1982-08-25
Also published as: EP0058449B1; DE3265932D1; NL8100710A; ATE15348T1

Abstract

The invention is related to a bale press with a device for shaping a passage for strapping up material comprising a plurality of strips corresponding with a desired number of straps, which strips during the shaping of the bale are sunk down in the head of the pressure plunger with the face turned away from the plunger on one line with the front face of the plunger, in which, in case the bale is formed said strips and the head of the press plunger is suited to move mutually with regard to each other in axial direction.

This known device does not work satisfactorily because in the case of dried gras, lucerne, household refuge or such material parts of the material come between the strips and the parts surrounding the strips in the head of the plunger, because of the fact that this material is very fine. As result of this the device will jam.

The invention aims to remove the above objections. '

According to the invention this aim is obtained by the fact that behind the front face of the head of the press plunger (2) a device is present that is connected to said strips (8) and is suited to retract them into the grooves (6) of the press plunger (2) in case the bale is to be strapped up.

Description

The invention is related to a bale press comprising a press passage, a press plungermovable to and fro in said press passage, a supply device debouching in said press passage for the material to be pressed into a bale, a device for forming passages between the head of the plunger and the back face of the bale for strap up material in case the bale has obtained the desired dimensions, a device for positioning stripping up material and for strapping up in tensioned condition and for cutting it as soon as the stripping up is completed in which the device for shaping the passage for strapping up material comprises a plurality of strips corresponding with a desired number of straps, which strips during the shaping of the bale are sunk down in the head of the pressure plunger with the face turned away from the plunger on one line with the front face of the plunger, in which, in case the bale is formed said strips and the.head of the press plunger is suited to move mutually with regard to each other in axial direction.
Such a device is known from practice (see also Dutch Patent Application 71.15077).
In the device known from practice the strips for shaping the passages when the bale is completed are locked and the plunger is retracted along some distance , so between the back face of the bale and the front face of the plunger a space is formed that by said strips is divided into a number of passages through which the strapping up material can be supplied, after which said stripping up material by twisting is formed into a loop encircling the bale and is cut from the supply of strapping up material.
This known device does not work satisfactorily in case short material as gras, lucerne in dried or not dried condition or household refuge has to be pressed into bales. The pressing into bales of household refuge is of particular importance as household refuge has to be transported along ever increasing distances in particular as at this moment continuously more refuge dumping grounds near towns and villages disappear. Such a transport is costly and this costs only can be lowered in case the volume to be transported is made as small as possible.
In the case of dried gras or lucerne or such material parts of the material come between the strips and the parts surrounding the strips in the head of the plunger, because of the fact that this material is very fine. As result of this the device will jam. In case of household refuge the danger of jamming is present in still greater measure. As is known usual household refuge contains a lot of moisture and a lot of small material. This material penetrates between the strips and the parts surrounding the strips in the head of the plunger. It appears not to be possible to obtain a good sealing between the strips and the head of the plunger as result of the fact that in case the plunger retracts, during which the strips keep their places, the full counterpressure of the bale on the head faces of the strips is exerted as result of which deformations may occur. The guiding of the strips in cross direction is, by the fact that the plunger is retracted and the strips are not moved, smaller what not contributes to the desired performance without troubles. Moreover by this it is not possible to provide sealing members between the strips and the surrounding material of the plunger head.
The invention aims to improve the above mentioned bale press in such a manner that the above objections are removed.
According to the invention this aim is obtained by the fact that behind the front face of the head of the press plunger a device is present that is connected to said strips and is suited to retract them into the groovesof the press plunger in case the bale is to be strapped up. By the fact that the strips are retracted in the plunger head for forming said passages the strips are not subjected to the high counterpressure of the completed bale that still have to be strapped up. The large remaining surface of the head of the plunger takes up this pressure without difficulties. Deformation of the strips does not occur. By the fact that the strips stay completely in the plunger head a good guidance of the strips is very well possible. Jamming of the strips in the plunger head is not to be feared and narrow tolerances can be used by which a good seal is obtained between the strips and the plunger head. The danger of failure is i small. Dirt possibly penetrated in the passages is removed when the stips are moved out of the passages. This avoids soiling strongly.
To still improve the correct guidance of the strips it is preferred that the strips are connected to a slide piece that in the frame of the plunger engages guide members. A preferred embodiment is obtained by the fact that the slide piece is connected with a member that is movable to and fro in longitudinal direction, which member is suited to move the strips to and fro and that can be locked in the position in which the face of the strips conincides with the face of the head of the plunger. A simple embodiment is obtained by the fact that the lockable member is formed by a toggle lever that at one side is connected to the slide piece and on the other side to the frame of the plunger and that by means of a cylinder-piston unit can be moved into and out of the locking position. However, it will be clear that also locking members working in axial direction are possible such as lockable cylinder-piston combinations, screw and nut members, and such.
With the known device the passages are only present in horizontal direction or in vertical direction. However., according to the invention both directions are present. For dried gras, lucerne and household refuge latter embodiment is preferred, in which usually four strips are present in longitudinal direction and in cross direction.
With the aid of a drawing in which the embodiment is shown, the invention will now be discussed in detail.

Fig. 1 shows a side view of the device according to the invention in which the strips pushed out and locked.
Fig. 2 shows the same side view as Fig. 1, with the strips retracted.
Fig. 3 shows a front view of the press plunger.

As known the pressure part of the bale press is formed by a carriage 1, a press plunger 2, a plunger rod 3, that engages a not shown plunger cylinder. The carriage 1 can (seen in Fig.l, 2) be moved from left to right and back when it is driven by the plunger rod 3. The carriage 1 runs with rolls 4 over rails or such (not shown) and the plunger presses material to be formed into bales into a press passage (not shown). This material is, in case the plunger is completely moved to the left dumped in the press passage via a not shown supply channel and subsequently is pressed into the press passage during the forward stroke of the press plunger.
Is sufficient material pressed together in the press passage then the shaped bale is strapped up as known and during the pressing of the next bale is pressed out of the press passage. To perform the placement of the strapping up material in position about the shaped bale between the front face of the press plunger and the shaped bale one or more passages for this strapping up material have to be formed in horizontal and/or vertical direction. According to the invention this is obtained by the fact that in the front face 5 of the press plunger a number of channels 6, mostly four of them, are formed. In Fig. 1 and 2 the horizontal channels 6 are indicated. As appears from Fig. 3 also vertical channels 7 are present. In these channels 6, 7 strips 8 are positioned that together form a grate as shown in Fig. 3. During pressing of the bale as indicated in Fig. 1 the front face 9 of the strips 8 are in line with the front face 10 of the press plunger. If pressing of a bale is completed then for shaping the passages for the strapping up material the strips .8 are retracted from the position indicated in Fig. 1 to the position indicated in Fig. 2. The press plunger here remains in its press position. As soon as in a manner known per se the strapping up material is threaded through the formed passages, is tied up and is cut from the supply, the press plunger moves to the left for subsequently forming a new bale after the strips 8 are brought back in the initial position as indicated in Fig. 1, and a preceding bale is pressed out of the passage.
According to this embodiment the indicated movement of the strips is obtained by means of a toggle lever mechanism, that in general is indicated with 11. This mechanism comprises a lever 12, that at one side is pivotly connected at 16 to a slide piece 13, and on the other side is pivotly connected at 15 to a lever 14, that on the other side is pivotly connected at 17 to the frame of the press plunger 1. This toggle lever mechanism 11 takes during pressing the bale the position as shown in Fig. 1, in which the pivot axis 15 is below the imaginary line drawn between the pivot axis 16 and the pivot axis 17. To the frame of the press plunger 1 and to the lever 14 a cylinder 18 is pivotly connected at 19, 20 respectively for actuating the toggle lever mechanism. Abutments 21 and 22 are present to limit the movement of the toggle lever. The slide piece 13 that at one side is connected to said toggle lever mechanism 11 and at the other side carries strips 8, in case the bale is pressed by means of the cylinder 18 moved from the position indicated in Fig. 1 to the position indicated in Fig. 2 and in case the bale is strapped up back to the position shown in Fig. 1. During this movement the slide piece 13 is guided by rollers 23, 24 present on the frame of the carriage.
From the drawing it will be clear that the strips 8 are enclosed in the front face of the press plunger 10 in such a manner that also thanks to the slide piece 13, guided by the rollers 23, 24, the formation as result of the countepressure exerted on the press plunger of the bale to be shaped and the formed bale still to be strapped up is avoided. Moreover by this it is possible to use small tolerances between the strips 8 and the channels 6 and 7, in such a manner that a good seal can be obtained between the strips ands the walls of the passsage. Moreover during going back from the position shown in Fig.2 to the position shown in Fig. 1 all material that possibly penetrated to the passages 6 and 7 is removed from those passages 6 and 7.
It will be clear that the toggle mechanism can be replaced by another type of lockable device.

Claims

1. Bale press comprising a press passage, a press plunger movable to and fro in said press passage, a supply device debouching in said press passage for the material to be pressed into a bale, a device for forming passages between the head of the plunger and the back face of the bale for strapping up material in case the bale has obtained the desired dimension, a device for positioning strapping up material and for strapping in tensioned condition and for cutting it as soon as the strapping up is completed in which the device for shaping the passages for strapping up material comprises a plurality of strips corresponding with a desired number of straps, which strips during the shaping of the bale are sunk down in the head of the pressure plunger with the face turned away from the plunger on one line with the front face of the plunger, in which, in case the bale is formed said strips and the head of the press plunger is suited to move mutually with regard to each other in axial direction, characterized in that behind the front face of the head of the press plunger device is present that is connected with said strips and is suited to retract them into the groove of the press plunger in case the bale is to be strapped up.

2. Bale press according to claim 1, characterized in that the strips are connected to a slide piece that in the frame of the plunger engages guide members.

3. Bale press according to claim 2 characterized in that the slide piece is connected with a member that is movable to and fro in longitudinal direction, which member is suited to move the strips to and fro and that can be locked in the position in which the face of the strips coincides with the face of the head of the plunger.

4. Bale press according 3 characterized in that the lockable member is formed by a toggle lever that at one side is connected to the slide piece and on the other side to the frame of the plunger and that by means of a cylinder-piston unit can be moved into and out of the locking position.