EP3873297B1 - Method for producing brushes and brush-producing machine - Google Patents

Description

The invention relates to a method for producing brushes and a brush manufacturing machine.

When manufacturing brushes, for example toothbrushes, household brushes or paint brushes, it is common for a brush base to be led one after the other to different processing stations, where a specific processing step is carried out in each case. For example, several holes can be drilled into the brush base at one processing station, and bundles of bristles are stuffed into the holes at a subsequent work station. To adjust the brush bases, slides are usually used that rotate along a predetermined path so that the bristle bases arranged on them are presented one after the other to the different stations for processing. In a simple example, the brush manufacturing machine has a loading station, a drilling station, a stuffing station and an unloading station. Then four slides can be used, each of which is adjusted one station further with each cycle of the brush manufacturing machine. The slides are usually attached to a drive element such as a common carrier or a chain, which adjusts all the slides together.

From the DE 17 57 612 A1 A brush drilling and tamping machine is known, with at least one drilling and tamping tool and a carriage on which several workpiece holders are arranged, which can be pivoted in one direction. The number of drilling tools is equal to the number of tamping tools and the number of workpiece holders is one less than the total number of these tools. In the first cycle of each machine cycle, a tamping tool lying in an edge position in the common axial plane is located above an empty space. This tamping tool, which is not working above the empty space, can be switched off so that it does not emit any tufts of bristles.

In addition, the DE 27 31 762 A1 a method for producing brushes that are manufactured in several partial operations of varying processing times, whereby the individual workpieces are fed to the successive processing stations simultaneously in a predetermined cycle. At the processing stations with a comparatively long processing time, at least two identical partial processing steps are carried out simultaneously.

A disadvantage of the known machines is that a certain amount of time passes when the carriages are moved from one processing station to the next, which has a negative effect on the productivity of the brush manufacturing machine.

To solve this problem, the DE 10 2014 103 599 A1 A brush manufacturing machine is known which is characterized by very short cycle times and thus high productivity. This well-known machine is described below using the Figures 1 to 3 described.

The brush manufacturing machine has a guide block 10 along which several carriages 12 can be adjusted in rotation.

Several processing stations 14, 16, 18, 20, 22, 24 are arranged around the guide block 10. When the carriages 12 are adjusted around the guide block 10, they move past the processing stations.

The guide block 10 is provided with a guide 26, the function of which is to attach the slides 12 to the guide block 10 in a movable manner. The guide 26 is intended in particular to ensure that the slides 12 are guided precisely and with as little tolerance as possible.

The guide 26 can, for example, be designed as a guide rail on which the carriages 12 are guided with rollers, rolling bearings or similar elements.

A drive device 28 is provided for adjusting the slides 12, with which each slide can be moved individually and individually around the guide block 10. The only limitation to the individual mobility of the slides is that no slide can overtake the other. Otherwise, each carriage can be moved individually and independently of the other carriages in terms of travel path and travel speed.

The drive device 28 can be formed, for example, by a drive motor on each carriage 12, which is coupled to a drive element, for example a drive wheel or a gear wheel, which in turn interacts with a corresponding counter element of the central guide block 10, for example a track or a rack. The drive device 28 can also be designed as a linear motor, which is assigned to the carriage and adjusts it contactlessly relative to the guide block 10. The drive device 28 can also be formed by several belt drives with which the carriages can be adjusted individually. By appropriately assigning the belt drives to the processing stations, it is possible to get by with fewer belt drives than there are carriages, since it is sufficient to adjust the carriages individually and independently of one another in the area of some processing stations, for example in the area of the drilling and tamping stations, for a minimized cycle time, while the carriages can be adjusted synchronously (and thus by means of the same belt drive) from a removal station to a loading station without this having a negative impact on the cycle time.

The drive devices mentioned are merely examples and not an exhaustive list.

At least one clamping device 30 for a brush base body 32 is attached to each carriage 12. In the embodiment shown, two clamping devices 30 are used per carriage. If necessary, more clamping devices can also be provided.

Each clamping device 30 can be pivoted or tilted about two axes. Firstly, a pivoting device 36 is provided with which each clamping device 30 can be pivoted about a pivot axis S. The pivot axis S is aligned parallel to the adjustment direction of the slides.

Furthermore, a tilting device 38 is provided with which the clamping device 30 can be tilted about a tilting axis K. The tilting axis K is perpendicular to the adjustment direction V of the slides 12.

Furthermore, a height adjustment 40 is provided, with which the carrier 34 can be adjusted in the vertical direction relative to the carriage 12, i.e. in the direction of the double arrow H.

With reference to the orientation of the brush manufacturing machine as shown in the Figures 1 and 2 As shown, the height adjustment 40 adjusts the carrier 34 in the vertical direction, i.e. up and down. The tilting device 38 can adjust the clamping device 30 associated with it, with respect to Figure 1 , clockwise and anti-clockwise around the tilt axis K (see also the double arrow K in Figure 1 ). The swivel device 36 can move the clamping device 30 associated with it, with respect to Figure 1 , clockwise and anti-clockwise around the swivel axis S (see also the double arrow S in Figure 2 ).

References such as "above" or similar are to be understood here merely as a reference to the figures. The brush manufacturing machine can also be arranged differently later, since the guide 26 does not have to be located in a horizontally extending plane, as shown in the drawings.

A control 48, shown schematically here, is provided for adjusting the slides 12 along the guide 26 and can be freely programmed as desired. Depending on the desired processing steps, the control 48 controls the speed and the steps at which the slides 12 adjust along the guide 26.

The processing stations can carry out different processing steps. In one example, the processing station 14 can be a loading station in which empty clamping devices 30 are loaded with brush base bodies 32 to be processed.

The processing station 16 is here a drilling station, in which a drill 50 is used to drill holes in the brush base body 32 with a back and forth movement along the direction of the double arrow B. The longitudinal adjustment of the brush base body 32 required here, i.e. along the adjustment direction V of the carriage 12 on the guide 26, is carried out by adjusting the carriage 12 in small steps relative to the processing station 16 by means of the drive device 28, for each column of holes to be drilled. Holes by the hole spacing. In the vertical direction, the brush base bodies 32 are adjusted by means of the height adjustment 40, specifically by the hole spacing for each row of holes to be drilled. If the holes in the brush base body 32 are to be drilled in directions that are not parallel to one another, the brush base body 32 is pivoted and/or tilted in a suitable manner by means of the pivoting device 36 and the tilting device 38.

The processing station 18 here is a stuffing station in which a stuffing tool 52, in a back and forth movement along the double arrow P, stuffs bundles of bristles 60, which are kept ready in a storage box 54, into the holes of the brush base body 32. Here too, the brush base body 32 is positioned relative to the stuffing tool 52 by appropriately controlling the drive device 28, the height adjustment 40, the pivoting device 36 and the tilting device 38.

The processing station 20 can be a removal station in which the brush base body 32 provided with bristle bundles is removed from the clamping device 30 or simply ejected.

Depending on the processing steps to be carried out by means of the brush manufacturing machine, further processing stations can be used. For example, a trimming station can be provided in which the bristles 60 attached to the brush base body 32 are cut and/or ground in order to obtain a desired length and/or a desired profile. In this case, the removal station 20, viewed in the adjustment direction V, will of course be arranged behind the trimming station.

The brush manufacturing machine can be coupled to an injection molding station, so that in an adjacent injection molding station the brush bodies are first injection molded or additional parts are molded onto previously manufactured brush bodies. From the injection molding station, these brush bodies are then transported manually or, preferably fully automatically, to the brush manufacturing machine and coupled into the brush manufacturing machine in the loading station. This can be done in various ways. If the carriers do not leave the brush manufacturing machine, the brush bodies are inserted into the carriers in the brush manufacturing machine. In addition, the carriers could also be loaded into the Manufacturing machine can be used in a loaded state. In the embodiment shown, however, the carriers circulate in the brush manufacturing machine and therefore do not leave it.

It is also possible to equip the brush production machine "double-equipped", i.e. in one half a loading station, various processing stations and an unloading station, and then in the second half another loading station, several processing stations and an unloading station. In this way, the number of brushes produced per cycle can be doubled.

The essential feature of the brush manufacturing machine described is that a brush base is pre-positioned before it is offered to the next processing station. This is done using Figure 3 explained. In Figure 3 the stuffing tool 52 can be seen, which is just stuffing the last holes of the brush body 32A with bristle bundles. Since the bristles 60, viewed in the top view of Figure 3 , are arranged in a fan shape, the bristle base body 32 must be tilted clockwise about the tilting axis K when it is guided past the stuffing tool 52 from left to right.

The bristle base body 32B to be processed next is pre-positioned accordingly by being tilted counterclockwise from a neutral position into the position shown before the carriage 12B carrying it reaches the processing station 18. In this position, the longitudinal axis L of the first hole to be filled in the brush base body B is aligned parallel to the filling direction P of the filling tool 52.

This pre-positioning can be done either during the feed movement from one processing station to the next or by stopping briefly immediately before the next processing station. This depends mainly on how far apart the processing stations are from each other and how time-consuming the pre-positioning is, which in turn also depends on the geometry of the brush to be produced.

When all holes in the brush base body 32A are filled with bristles, the carriage 12A is further adjusted in the adjustment direction V, and at the same time the carriage 12B is also further adjusted in the adjustment direction V. Since the brush base body 32B is already "correctly" aligned, the stuffing tool 52 without any time delay. In practice, the brush base body 32B in the pre-positioned state can be brought much closer to the currently processed brush base body 32A than is possible in Figure 3 is shown. Then, when the processing progresses from the brush base body 32A to the brush base body 32B, the brush base body 32B only needs to be adjusted minimally in the longitudinal direction (i.e. in the adjustment direction V). In the optimal case, the necessary adjustment movement is so small that the tucking tool can continue to work uninterrupted and the adjustment does not differ, or at least not noticeably, from the adjustment that is necessary when tucking one and the same bristle base body from hole to hole.

It can be seen that the rate at which brush bases can be drilled and then fitted with bristles depends on the "slowest" of the two stations, drilling and plugging; since as many holes have to be drilled for each brush base as there are to be plugged, neither of these two stations can work faster than the other. If it does, it must then wait until the other station has finished processing.

It has been found that drilling the holes is currently the "bottleneck". In view of the fact that the drilling chips have to be removed from the hole and the fact that the material cannot be processed as quickly as desired (with brush bases made of plastic there is a risk that the material will melt), the processing limits have currently been reached with conventional drills and conventional drilling techniques.

The object of the invention is to provide a method for producing brushes and a brush manufacturing machine with which the processing speed can be further increased.

To achieve this object, the invention provides a method for producing brushes by means of a brush manufacturing machine according to claim 1 and a brush manufacturing machine according to claim 8.

The invention is based on the basic idea of dividing the work of drilling holes in the brush body into two or more drilling stations and adjusting the cycle speed of the drilling stations according to the ratio of drilling stations to tamping stations. This allows the holes to be drilled at two-thirds the cycle speed (if there are three drilling stations and two tamping stations), half the cycle speed (if there are twice as many drilling stations as tamping stations) or one-third, one-quarter, ... the cycle speed (if there are three, four, ... drilling stations) used for tamping. This leaves enough time to drill the holes with standard drills without having to resort to complex techniques that could further increase the drilling speed.

"Cycle speed" means the rate at which a cycle (e.g., plugging a hole or drilling a hole) can be performed. For example, if there are two drilling stations at one plugging station, a cycle speed of 50 holes/sec. may be used for drilling and a cycle speed of 100 holes/sec. may be used for plugging. Accordingly, "cycle ratio" means the ratio of the number of different stations to each other and the resulting reduction in the cycle speed of the drilling stations relative to the cycle speed of the plugging stations.

If there are two drilling stations, one embodiment can provide that the hole pattern drilled by one of the drilling stations corresponds to the hole pattern drilled by the other drilling station, shifted by one row of holes. This reduces the effort required to program the drilling pattern, since the drills for the two drilling stations can be adjusted synchronously. At most, a small adjustment of the angle of the brush base body is necessary if the orientation of the holes drilled at the same time differs from one another.

It can also be planned that all drilling stations drill exactly the same hole pattern, but the brush base bodies are then adjusted further when a drilling station has drilled "its" part of the hole pattern. This reduces the programming and control effort for the drilling stations, since only a single hole pattern needs to be programmed.

To further reduce the control effort, the drilling stations can be operated synchronously with each other.

The carriages are preferably moved further within the two drilling stations and the tamping station simultaneously, i.e. synchronously from the first drilling station to the next, from the second to either the next or the tamping station, and from the tamping station to another processing station. This reduces the cycle times for completing a brush.

• Figur 1 eine Bürstenherstellungsmaschine aus dem Stand der Technik in einer schematischen Draufsicht;
• Figur 2 schematisch einen Schnitt entlang der Linie II-II von Figur 1;
• Figur 3 in einer vergrößerten Ansicht eine Bearbeitungsstation mit einem aktuell bearbeiteten Borstengrundkörper und einem vorpositionierten, anschließend zu bearbeitenden Borstengrundkörper; und
• Figur 4 in einer schematischen Draufsicht eine erfindungsgemäße Bürstenherstellungsmaschine.

The invention is described below with reference to the accompanying drawings, in which:

• Figure 1 a brush manufacturing machine from the prior art in a schematic plan view;
• Figure 2 schematically a section along the line II-II of Figure 1 ;
• Figure 3 in an enlarged view, a processing station with a currently processed bristle base body and a pre-positioned bristle base body to be subsequently processed; and
• Figure 4 in a schematic plan view a brush manufacturing machine according to the invention.

In Figure 4 An embodiment of a brush manufacturing machine according to the invention is shown. For the Figures 1 to 3 The same reference numerals are used for known components and reference is made to the above explanations.

The difference between the Figure 4 Brush manufacturing machine shown and the one in the Figures 1 to 3 The advantage of the brush manufacturing machine shown is that in the embodiment according to Figure 4 two drilling stations are present, namely a drilling station 16A and a drilling station 16B.

The two drilling stations 16A, 16B as well as the tamping station 18 are controlled by a controller 48.

Another difference between the brush manufacturing machine known from the state of the art and the one in Figure 4 The advantage of the brush manufacturing machine shown is that in the brush manufacturing machine according to the invention A cycle divider module 49 is provided for the brush manufacturing machine. This is integrated into the control system 48.

The cycle divider module is used to specify the cycle speed for the two drilling stations 16A, 16A, in a fixed reduction ratio relative to the cycle speed of the tamping station 18. This reduction ratio corresponds to the ratio of the number of drilling stations to the number of tamping stations. In the embodiment shown, one tamping station 18 and two drilling stations 16A, 16B are used. Accordingly, the cycle divider module 49 reduces the cycle speed of the tamping station 18 in a ratio of 2:1. In other words: the cycle speed of the drilling stations 16A, 16B is half the cycle speed of the tamping station.

The reduction ratio can be adjusted depending on the configuration of the machine, but is constant during machine operation.

In order to achieve a high overall cycle rate, each drilling station 16A, 16B drills half of the holes that need to be drilled in a brush base body 32.

It can be provided that the brush base bodies 32 in the drilling stations 16A, 16B are moved synchronously with one another, so that the drilling station 16A drills the holes 1, 3, 5, 7, ... of a row of holes in a brush base body 32, while the drilling station 16B synchronously drills the holes 2, 4, 6, 8, ... of the same row of holes in another brush base body 32.

It may also be provided that the order in which one half of the holes are drilled by the drilling station 16A differs from the order in which the drilling station 16B drills "its" half of the holes.

It is particularly preferred that all drilling stations are operated synchronously, i.e. drill the same complete hole pattern at the same time. This is shown below using Figure 4 explained.

If one considers a specific brush base body that is moved along the guide, it first encounters the drilling station 16B. This drills (in this example at half the cycle speed of the stuffing station 18) all the holes that need to be drilled on a bristle base body. For example, it starts on the left side of the brush base body 32 and initially drills all the holes on the left side.

After the drilling station 16B has drilled the last hole in the left half of the brush base body 32, the carriage is moved further so that a new brush base body 32 is fed to the drilling station 16B. Since the drilling station 16B always drills a complete hole pattern, the holes are now drilled on the right half of the brush base body 32, but on a "new" brush base body.

The "old" brush base body 32 has been transported to the drilling station 16A, where the holes are now being drilled on the right half of the old brush base body.

When this is completed, the carriages are again advanced so that the drilling station 16A now drills the holes on the left side of the next brush body, while the drilling station 16B drills the holes on the right side of a "new" brush body.

What is crucial is that each drilling station has as much time available to drill "its" holes as the stuffing station needs to stuff all the holes of a brush base body 32 with bristles.

Claims (8)

1. A method of brush manufacturing by means of a brush manufacturing machine having a guide (26) along which a plurality of slides (12) can be successively moved to a plurality of drilling stations (16A, 16B) and then to at least one tufting station (18), the drilling stations (16A, 16B) being operated simultaneously with the at least one tufting station (18), and the number of drilling cycles performed by each drilling station (16A, 16B) per unit of time being equal to the number of tufting cycles of the at least one tufting station (18) in the same unit of time, divided by the ratio of the number of drilling stations to the number of tufting stations, wherein the drilling of the holes in the brush base body is divided between two or more drilling stations and the cycle speed of the drilling stations is reduced in accordance with the ratio of the drilling stations to the tufting stations.
2. The method according to claim 1, characterized in that exactly two drilling stations (16A, 16B) are provided, which are operated with half the cycle speed of the tufting station (18).
3. The method according to claim 2, characterized in that the hole pattern drilled by one of the drilling stations (16A, 16B) corresponds to the hole pattern drilled by the other drilling station (16B, 16A), shifted by one row of holes.
4. The method according to claim 3, characterized in that exactly three drilling stations (16) are provided, which are operated with one third of the cycle speed of the tufting station (18).
5. The method according to any of the preceding claims, characterized in that the drilling stations (16) are operated synchronously with each other.
6. The method according to claim 5, characterized in that all drilling stations (16A, 16B) drill exactly the same hole pattern, but the brush base bodies (32) are then shifted further when a drilling station has drilled a portion of the hole pattern corresponding to the cycle ratio.
7. The method according to any of the preceding claims, characterized in that the slides (12) are simultaneously shifted further within the two drilling stations (16A, 16B) and the tufting station (18).
8. A brush manufacturing machine, in particular for carrying out the method according to any of the preceding claims, having a guide (26), a plurality of slides (12) which are adapted to receive one or more brush base bodies (32) and are adjustably received at the guide (26), a plurality of drilling stations (16A, 16B) and a tufting station (18), the guide (26) extending along the plurality of drilling stations (16A, 16B) and then along the tufting station (18), and having a control (48) including a cycle dividing module (49) which steps down a cycle speed of the tufting station (18) to a cycle speed of each drilling station (16A, 16B) which is an nth of the cycle speed of the drilling station (18), n being the number of drilling stations (16A, 16B) in relation to the number of tufting stations (18), wherein the drilling of the holes in the brush base body is divided between two or more drilling stations and the cycle speed of the drilling stations is reduced in accordance with the ratio of the drilling stations to the tufting stations.

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