FR2601329A1 - Method and device for filling a tubular bag with a solid material in powder or granulate form and bag for implementing the method and the device - Google Patents

Abstract

Method for filling a tubular bag 1, open at one end 3, with a solid material in powder or granular form, which consists: - in separating the two lips of the open end of the bag in order to form a filling orifice; - in placing this orifice in a leaktight manner over a filling chute 6 connected to a hopper containing the said material to be loaded; - in conveying air into the bag 1 in order to unfold it; - in opening the hopper 12, 13 in order to fill the bag, characterised: - in that the bag 1 is seized by a set of grippers 64, 65 and 64', 65' in the vicinity of its open end 3; - and in that the said grippers are brought together in order to form a filling orifice.

Description

METHOD AND DEVICE FOR FILLING A BAG
TUBULAR WITH A POWDER-LIKE SOLID MATERIAL OR
OF GRANULES AND BAG FOR IMPLEMENTING THE PROCESS AND
OF THE DEVICE.

The invention relates to a method for filling a tubular bag, open at one end, with a solid material in the form of powder or granules, in particular of large capacity (250 liters and more), it also relates to a device for carrying out this process, and a bag for carrying out the process and the device
The loading operation of large capacity bags (250 liters and more) poses more and more problems in the chemical industry and in the food-processing industry.
- arrange the two lips of the open end
of the bag to form a filling opening
- place this orifice forming the loading chimney
on a filling chute connected to a tré
crumb containing the material to be loaded
- send air into the bag to unfold it
- and finally to open the hopper to load the bag.

Unfortunately, although these techniques are widely used, the filling quality is not always very perfect, especially with pulverulent materials, probably as a result of poor compaction, and above all these operations cannot be automated. In addition, it is difficult to fix the bag filling chute on existing devices
The invention overcomes these drawbacks. It aims at a process which improves the filling of the bags, which is economical and easily automated.

This process for filling a tubular bag, open at one end, with a solid material in the form of powder or granules, consists
- to separate the two lips from the open end
of the bag to form a filling orifice,
- place this orifice tightly on a
filling chute connected to a cone hopper
holding said material to be loaded
- send air into the bag to unfold it
- to open the hopper to fill the bag
The invention is characterized:
- in that the bag is gripped by a set of pliers in the vicinity of its open end
- and, in that the tongs are brought together to form a filling orifice
Advantageously, in practice
- during the loading of the bag, the open end of the bag is driven by alternating permanent movements of ascent and descent, so as to ensure good compaction and a homogeneous distribution of the product
- Once the bag is filled, it is rotated on itself or around its vertical axis so as to form a twisted neck at the free end of the bag, then the twisted portion thus formed is ligated.

- the individual bags are wound in series one after the other to form a roll, said roll being unfolded on a support until presenting a unitary bag, which is then gripped by the set of pliers squeezing the lips of the open end, cause it to slide on the support, and bring it to a vertical position
The invention also relates to an automatic device for implementing this method. This automatic device which comprises in known manner
- a loading hopper associated with a chute
filling
- means for placing the open orifice of the bag
tightly around said chute
- means for blowing air into the bag
before filling, is characterized in that it also comprises
- a set of pliers intended to grip the open end of a unit bag
- cylinders, integral with the filling chute, intended to ensure the closing of the clamps on the bag,
- pistons, intended to bring the said pliers towards one another
Advantageously, in practice
- the filling chute is articulated on jacks associated with a member intended to animate them with an alternating permanent movement of ascent and descent, with controlled tension on the bag, and to accompany the shortening of said bag, caused by filling
- the bag being filled, rests on a turntable around the vertical axis of the chute
- the device also includes
. a support intended to receive the plain bags
shut up
. means for sliding the seized bag to
its end on the said support
- The sliding of the bag seized on the support is ensured by the pivoting of the gripping cylinder on the filling chute, and by the rise of the latter.

 Finally, the invention also relates to tubular bags for the implementation of the above device.

These bags are characterized in that each of the two lips forming the opening of the tubular bag has a rigid elastic maneuvering plate, the length of which corresponds substantially to the spacing between the two sets of clamps, when the latter are not actuated.

 The manner in which the invention can be carried out and the advantages which ensue therefrom will emerge more clearly from the examples of embodiment which follow, given by way of indication and without limitation in support of the appended figures.

 Figures 1 to 5 show different embodiments of the bag according to the invention.

 FIG. 7 is a detailed view of the loading head of the device according to FIG. 6.

 Figure 8 shows a characteristic gripper according to the invention.

 Figures 9 to 12 schematically show the preparation phases of the process according to the invention.

 Figures 13, 14 and 15 show roughly different stages of the loading operation.

For reasons of convenience and ease of understanding, any organ or symmetrical element of an organ or element referenced, will bear the same reference with the prime symbol (')
The tubular bag characteristic of the invention shown in Figure 1, designated by the general reference (1) is made of any suitable material compatible with the material to be received (granules, powder, etc.). It can advantageously be a woven polypropylene fabric. This tubular bag (1) is closed at the bottom by a bottom seam (2) and is open at its opposite end (3). The lips respectively (4) and (5) which form this free opening (3) each comprise a flexible blade (6,6 ') held on the edge by seams (7) and (8). These characteristic operating plates ( 6.6 ') such as sheet steel, plastic or thick cardboard blades, must be flexible, rigid and elastic. The intervals between the two seams (7) and (8) form an open pocket which thus perfectly receives the operating plates (6,6 ') whose edges are supported on said seams (7) and (8). These seams (7,8) can be replaced by equivalent means such as staples or rivets
In a variant shown in Figure 2, the operating plates (6,6 ') are introduced into a sewn loop (9) provided for this purpose. In the variant shown in Figure 3, the operating plates (6,6 ') are simply held in place by a plastic sheet (10) welded along the dotted line (11), in order to form gusset.

 As can be seen in FIG. 5, it is understood that if the edges of the maneuvering plates (6,6 ') are brought together in the direction indicated by the two arrows F and F', an opening in the form of fireplace.

 In order to be sure of the correct opening of the free end (3) of the bag (1), the maneuvering plates (6,6 ') may have a notch of middle fold, which during the action forces F and F 'cause a repulsive effect, thus guaranteeing the formation of a chimney-shaped opening.

In practice, the bag (1) is folded across its width to facilitate handling and filling
The loading device according to the invention shown in FIGS. 6 and 7 essentially comprises a loading hopper (12) intended to receive said material in the form of granules or the like. An opening valve (13), pneumatically or electronically controlled, sends the products to a flow chute (14), coaxial with the loading chute (16) proper. A seal (15) provides a summary seal to the passage of air. The chute (16) is integral with a frame (17) articulated, by semi-rigid connections (18) of the "silent-block" type, on operating cylinders (20) integral with support elements (19), in this case, support legs (19).

These jacks can, among other things, transmit to the said frame (17), an alternative up and down mcuv-ment.

A flexible hose (21) connects the loading chute (16) to an air intake (22) (figure,) intended to inflate the bag during the filling operation. The rigid frame (17) is integral with a support sleeve (23) at the end of which is placed the waterproof loading head (24) which has two seals (25,38) for filling it. a seal clamping support (26). Thanks to ball bearings (27,28), the frame (17) supports two support tubes (29,29 '), arranged on either side of the loading chute (16). The suportort tube (29) contains a frame (35,68) comprising two vertical cylinders (30,30 ') (shown in detail in Figure 8), animating the jaws (64,65) of the loading clamps. comprises a round axis (35), sliding in the tube (29), with a flat (68), supporting the jaws (64,65) of the loading clamps
In line with the presence of the dish (68), the tube (29) has a slot (69) allowing it to pass through the operating part of this dish, as indicated in FIG. 8
The loading clamps consist of a fixed jaw (64) and a movable jaw (65), actuated by the jack (30), in order to pinch the free edges (33,34) of the bag (1) ( See figure (4,5). These jaws (64,65) just pinch the bag in the vicinity of the end and preferably outside of the operating plates. The bringing together of the two clamps (64,65) and ( 64 ';65') in the direction indicated by the arrows F and
F ', so as to form the opening, is provided by a piston (36.36') integral with the axis (35.35 '), acting in an air blowing chamber (37.37') , associated with a return spring (39.39 '). By sending air as indicated by arrows P and P 'into the chambers (37,37'), the piston is moved respectively (36) and (36 ') in the direction indicated by arrows F and F'
Several jacks, for example three in number (42), fixed to the sheath (23) make it possible to raise and lower the sealing head (24) and thereby ensure contact between the seal (25) and the opening (3) created by the maneuvering plates (6,6 ')
Two jacks (60.60 ') integral with the frame (17) and the flat support (68.68') of the clamps in (67) and (67 '), allow the clamps (64.65) to be placed in horizontal position and (64 ', 65'), as shown in Figures 9 to 12. The loading process is indicated in these figures
According to a characteristic of the invention, the individual elementary bags are wound up in the form of rolls (40), themselves fixed on an axis (63). They are placed near an inclined support (41). Thanks to the ball bearings (27,28) and (27 ', 28'), and to the action of the jacks (60,60 '), the two clamps are brought into the horizontal position as shown in Figure 10, the jaws (65) and (65 ') being open under the action of the cylinders (30,30').

 The bag (44) slides on the inclined support (41), and the edges (33,34) of said bag, are placed between the open jaws (64,65) on the one hand and (64 ', 65') on the other hand. The end of the bag is perfectly grasped when the two jaws close. It goes without saying that the unwinding of the roller (40) must be carried out in synchronism with the individual gripping of the ends (33) and (34) by the jacks (30, 30 ').

Advantageously, the angle of inclination of the support (41) is of the order of 15 "relative to the horizontal.

By an appropriate device shown in Figure 6, the jacks (20) are mounted as shown in Figure 10. The bag (44) whose end is gripped is thus pulled up. The upward movement (see Figure 11) of the cylinder continues until the cylinder (20) is fully extended. The clips are then pivoted around the axes (35) and (35 ') in order to replace them in the vertical position, while part of the bag support retracts so that the latter is found in the vertical position. The bag being brought to the vertical position (see Figure 6), air is sent to the chambers (37) and (37 '). The clamps move according to the arrows F and F', creating the opening of the mouth from the bag
The jacks are then actuated (42) so as to lower the loading head (24) and ensure the being cheïté on the joint (25). Air is blown into the bag by a fan (22). The valve (13) is then opened to ensure filling (Figure 14). During this entire loading operation, the bag rests on a pallet (46) which itself rests on a turntable (47), and the entire loading head (24) is driven in an alternating movement by the intermediary of the frame (17), linked to the jacks (20), in order to ensure a gradual compaction of the product. This movement is ensured by a member designated under the general reference (50), shown in detail in FIG. 6. organ comprises, in order, an oil reserve chamber (51), with its piston (52), associated with a pressure regulation member (54), itself comprising a piston (58), a calibrated spring (55), and a plug (56), an actuating piston (53), associated with a valve (59), which makes it possible to distribute the oil flow either in the circuits (57) or in the chamber (51) and circuits (57)
When you want to mount the cylinders (20) just push on the piston (52) to send oil in the circuits (57), after opening the valve (59)
To ensure the up and down movement, the valve (59) is closed and the piston (53) is pushed. The oil passes into (57) and (54), raise the pistons (20) until the piston (58) clears the light (43), and the oil passes into the reserve (51). When the piston (53) is released, the piston (58) descends and closes the light (43), the pistons (20) descending lower than they were before the previous displacement of the piston (53) by height equal to the ratio of the volume of oil transferred in (51), divided by the total section of the cylinders (20)
The light (43) is released when the spring thrust is exceeded, which is calculated to be equal to the weight of the loading head, added tension on the bag equal to a predetermined weight, for example, 150 or 250 Kg
Thus, this up and down movement is carried out at controlled tension on the bag canvas. The distribution of the product is completely homogeneous, and the filling head drops as the filling progresses, accompanying the inevitable shortening of the bag.
When the loading operation is complete (see FIG. 15), the plate (47) is rotated to thereby form a twisted neck (48), which is then ligated.

The invention has many advantages over the solutions known to date. We can cite
- automatic gripping of the bag :,
- the use of a lower fabric grammage for making bags, since it is not intended to be handled by vertical gripping
- automatic formation of the twisted neck
The assembly can be further automated if we add an automatic stringing device, like those already on the market
In this way, the invention can be successfully used for filling bags of large capacity, that is to say of 250 liters or more, by means of solid materials in the form of granules and especially in powder form.

Claims (10)

 1 / Method for filling a tubular bag (1) open at one end (3), with a solid material in the form of powder or granules, which consists  - to separate the two lips from the open end  of the bag to form a filling opening  - place this orifice tightly on a  filling chute (16) connected to a hopper  containing said material to be loaded  - to send air (21) into the bag (1) for the  unfold  - to open the hopper (12,13) to fill the bag characterized:  - in that the bag (1) is gripped by a set of pliers (64,65) and (64 ', 65') in the vicinity of its open end (3)  - And, in that we bring together said clamps to form a filling orifice  2 / A method according to claim 1, characterized in that during the loading of the bag (l), the open end (3) thereof is animated with permanent alternating movements of ascent and descent, so as to ensure good compaction and even distribution of the product  3 / Method according to one of claims 1 and 2 characterized in that when the bag (1) is filled, it is rotated on itself around its vertical axis so as to form a twisted neck (48) at the 'free end (3) of the bag (1), then, in that we ligate the twisted portion thus formed.  4 / Method according to one of claims 1 to 3 characterized in that the individual bags (1.44) are wound in series one after the other to form a roll (40), and in that said roller ( 40) is unfolded on a support (41) until presenting a unitary bag (44), which is then gripped by the set of pliers (64,65,64 ', 65') tightening the edges (33,34) of the open end (3), then cause it to slide on the support (41) to bring it into vertical position, by the rise of the loading head (24) and the pivoting of said clamps  5 / -Automatic device for implementing the method according to one of claims 1 to 4, comprising:  - a loading hopper associated with a chute  filling (16)  - means for placing the open orifice (3) of the  bag (1) tightly around said  chute (16)  - means for blowing air (21,22) into  the bag (1) before filling, characterized in that it also comprises  - a set of pliers (64,64 ', 65,65') intended to grip the open end (3) of a unit bag (1,44);  - cylinders (30.30 '), integral with the filling chute (16), intended to ensure the closing of the clamps (64.64', 65.65 ') on the bag (1.44)  - pistons (36,36 ') intended to bring the said clamps towards one another  6 / Device according to claim 5, characterized in that the filling chute. (16) is articulated on jacks (20) associated with a member (50) intended to animate them with a permanent alternating movement of ascent and descent , with controlled tension on the bag, and to accompany the shortening of said bag, occasioned by the filling  7 / Device according to claim 6, characterized in that the bag (1.44) during filling, rests on a turntable (47) around the vertical axis of the filling spout (16)  8 / Device according to claim 7, characterized in that it also comprises  a support (41) intended to receive the unitary bags (1,44)  means for sliding the grasped bag (1.44) at its end onto said support (41)  9 / Device according to claim 8, characterized in that the sliding of the bag (1.44) gripped on the support (41) is ensured by the pivoting of the gripping cylinder (60.60 ') on the filling chute (16 ), and by the rise of it  10 / tubular bag (1.44) for the implementation of the method and the device according to one of claims 1 to 9, characterized in that each of the two lips (4,5) forming the opening (3) of the tubular bag (1) has a rigid and elastic maneuvering plate (6,6 '), the length of which corresponds substantially to the spacing between the two sets of clamps, when the latter are not actuated.