DE2746287A1 - Wiping roller for cleaning copying drums - has core with glued-on foam jacket which is cut into rings in situ - Google Patents

Abstract

Mfr. of a foam roller composed of a rigid core having closely adjacent foam rings fitted over it, comprises (a) coating the core in that region to be fitted with foam rings, with a hot-melt adhesive; (b) slipping a foam tube over the core when the adhesive has cooled; heating the core to m.pt. of the adhesive; and (c) slicing the foam tube into foam rings after the adhesive has cooled, and machining to accurate circumference. Before the foam tube is slipped over the core the latter is coated with a lubricant, suitably a liq. silicone, or a powder, e.g. talcum or Zn-stearate. Roller is inexpensive ot mfr. within required tolerances of prodn.

Description

description

The invention relates to a method and apparatus for producing a Foam roller with a rigid roller core and close to each other on this fixed foam rings.

Such a wiping roller is used in a cleaning cassette for copying drums used, which is known from DT-PS 2,332,830. The well-known cleaning cartridge contains a supply of nonwoven tape that is removed from the back of the cassette Inside the cassette, over the top of the cassette and over the one on the Front of the cassette arranged wiper roller is guided and then back into the interior of the cassette is passed. Ribs that attach to the wiping roller adjacent, sloping side wall of the cleaning cartridge perpendicular to the plane of this inclined side wall and on both sides of this side wall are arranged and between the foam rings of the wiper roller up to the Engage the roller core, serve on their outside to guide the nonwoven belt to the wiping roller and on the inside thereof, the nonwoven fabric tape from the wiping roller to separate. Since the entire cassette and its contents are designed as a disposable cassette is to be, the requirement arises that the individual parts as possible have to be manufactured cheaply, but they fulfill the task set them have to. With regard to the wiper roller, this means that the foam rings are on the roller core must be firmly fixed that the slots between the foam rings with high accuracy at certain points have to sit and that the outer circumference of the wiper roller must also correspond very precisely to the nominal dimension. Deviations in these points lead to the nonwoven webbing from the wiping roller does not make satisfactory contact with the surface of the copy drum is held so that the copy drum is not cleaned sufficiently, or that the nonwoven tape is not transported further enough, or finally, that the nonwoven tape wrinkles or shifts over the wiping roller.

Practical testing has shown that indeed the manufacturing tolerances of the wiper roller are kept within very narrow limits must, so that there are corresponding problems in the manufacture of the wiper roller and result in the design of the corresponding device.

The invention is therefore based on the object of the wiper roller as possible to manufacture inexpensively and with the necessary manufacturing tolerances.

The solution to this problem is characterized in claims 1 and 11 to 13, while the remaining claims characterize advantageous embodiments of the invention.

Embodiments of the invention will now be based on the enclosed Drawings described. They show: FIG. 1 a cleaning cassette with paper tape for cleaning a schematically shown copier drum; Fig.2 is a plan view of the essential parts of a device in order to pull a on the roll core Cut foam tube into foam rings and around the foam tube or to process the foam rings to an even extent; Fig. 3 a side view of the device shown in Figure 2; and FIG. 4 shows a device around the roller core up to the melting point between the roller core and the real foam tube the hot glue that is located.

According to Fi # .1, the cassette 2 consists of a cassette sub-part 4, a cassette upper part 6 and a wiper roller 8, which in a front opening the cassette 2 is stored. The interior of the cassette is surrounded by a partition lo divided into two chambers, and a paper web 12 is from a storage chamber 14 via a rear closure 16, a rear, straight side wall 18 of the upper part of the cassette 6, the bottom 20 of the upper part of the cassette, at the front over the wiping roller 8 into the chamber 22 led. At the front of the cassette, the upper part of the cassette has an incline extending side wall 24 carrying thin-walled ribs 26 perpendicular to the Stand level with the side wall 24 and extend from the side wall 24 on both sides. The ribs 26 extend between individual foam rings 28 (Figure 2), the form the outer part of the wiper roller 8, up to the roller core 30 of the Wiper roller 8. The ribs 26 serve to keep the paper web 12 on the front the cassette and the paper web 12 on the back of the wiper roller to strip from this. For cleaning the copying drum 32 shown schematically is the wiping roller 8 with the paper web 12 drawn over it with the copying drum in touch. The wiping roller 8 itself is driven in use.

The following first describes the method for producing the wiper roller described with reference to Fig.2. The roller core 30, in this embodiment, a Steel pipe, is cut to length cut and deburred. Then will the roller core cleaned, for example with trichlorethylene.

Hot-melt adhesive rings 34 are placed on the roller core prepared in this way applied that the hot melt adhesive rings within the sections of the roller core which are covered by the foam rings 28 after the wiper roller has been completed will. Under each of the foam rings 28 there are two hot-melt adhesive rings, while only one hot-melt adhesive ring in the areas of the later lateral foam rings 36 34 is present. The hot glue rings can be applied semi-automatically a roller is made, which is immersed in a bath with hot glue and with appropriate, profile-like roll projections with the roll core 30 is in contact.

Rotation of the profile roller and the roller core 30 then results the hot-melt adhesive rings 34 on the roller core. Instead of the profile roller, of course Rotating transmission disks can also be used to secure the hot-melt adhesive rings 34 to apply. When carrying out the process in practice, the hot glue is used a hot melt adhesive from Henkel in Düsseldorf under the product number Q 2283 used, which is set to a melting temperature of 150 C.

After the hot-melt adhesive rings 34 have cooled down, this is supported by an air blower can be, the roller core 30 with the adhesive rings 34 is with a liquid or powdered lubricants, for example silicone, talc or zinc stearate, coated. This lubricant is used to remove the per se friction-intensive peripheral surface To make the roller core 30 slidable and thus the subsequent mounting of a Foam tube to facilitate.

On the roller core 30 provided with lubricant with the hot-melt adhesive rings 34 a foam tube is then drawn up, in practice a foam with a specific gravity of 30 to 50 kg / m3 is preferred.

However, the term foam is used here for all of them Substances that have a restoring force when subjected to mechanical stress, for example also rubber or an elastic plastic. To when pulling up the foam tube Generating as little internal stress as possible in the hose from the start becomes a facility used, which engages in the inner diameter of the foam tube and this slightly expands so that the foam tube as a whole over the roller core 30 can be pushed. After aligning the foam tube on the roller core the foam tube is worked diagonally back and forth several times in order to possibly Eliminate any remaining inherent tensile stress. This manufacturing state is shown in Figure 2 to the left of the center line M, the outline of the foam tube by dashed line 38 and the cuts to be made later by dashed lines Lines 40 are shown.

The roller core 30 with the foam tube is up to the melting point of the hot glue is heated. The hot-melt adhesive rings 34 are activated and fix the foam tube on the roller core 30 when the hot glue is back has cooled down. The adhesive connection between the foam and the roller core 30 takes place in the areas 32, which in Figure 2 to the right of the center line M in plan view are shown.

It should be noted that the arrangement of the hot melt adhesive rings 34 ensures that the sections of the roller core between the areas 42, ie. the sections of the roller core, in which later the cuts for the production of the foam rings 28 are placed, remain free of hot glue, as shown in Fig.2.

Now that the foam tube is firmly connected to the roller core and the hot glue has cooled down, the foam tube is wrapped in foam rings cut up and processed to an even extent. Cutting up the foam hose in foam rings 28 can before or after the operation in which the Foam is processed to an even extent, and with a Grinding or milling tool. This stage of manufacture of the wiper roller is in Fig. 2 to the right of the center line partly in section (immediately next to the Center line M) and partially shown in plan view (at the right end of the wiper roller).

To reduce the frictional resistance between the cleaning cassette when it is finished to reduce ribs 26 dipping between the foam rings 28 and the foam, a liquid or powder lubricant can also be placed between the foam rings 28, for example silicone, talc or zinc stearate or the like, are filled.

After attaching a gear bushing (for the drive of the wiper roller) and a bushing at the opposite end into the inside of the tube on the end faces of the roller core is the wiping roller for the transfer to the overall assembly of the cassette completed.

In the following, devices are described with reference to Figures 2 to 4, used in the manufacture of the wiper roller will. in the The upper part of FIG. 2 shows a grinding stone roller So which is used for the provided outer diameter of the foam tube or the foam rings to manufacture. The grinding stone roller 50 can either consist of a Sffi-ück, as shown at 52 to the right of centerline, or there may be several Divide as shown to the left of the center line M.

In the case of the multi-part design of the grinding stone roller 50, there are Schisifstein rings 54, 56 are provided, the inner end faces 58 of which are inclined to the axis of the grinding stone roller lie and the outer surfaces 60 of the cylindrical surface of the grindstone roller form, the outer end faces 62 of the end grinding stone rings 56 perpendicular to the grinding stone roller. The multi-part design of the grindstone roller has the advantage that individual grindstone rings can be replaced when worn. This reduces tooling costs, which is desirable as the grindstone material is expensive.

In the lower part of Figure 2, a cutter bar 64 is shown, the Separating knife 66 carries. By this cutter bar with the arrangement shown in Figure 2 the cutting knife 66 is before or after the grinding of the outer diameter of the foam the foam is cut to form the foam rings 28.

3 shows a schematic side view of the grindstone roller, the roller core 30 with a foam ring 28 and the cutter bar 64 with the Cutting knives 66. The working position of the grinding stone roller So and the cutting knives 66 is shown in dashed lines. In the arrangement of Figure 3 are the grindstone roller So and the cutter bar 64 can be moved back and forth in the direction of the roller core 30 executed. The order can of course also be taken that way be that the axis of the grindstone roller 50 is fixedly mounted, then the required relative movement between the grindstone roller So and the roller core 30 is made possible by mounting the roller core 30 so that it can move back and forth. The same applies to the relative movement between the roller core 30 and the cutter bar 64. The grinding stone roller is rotatably mounted, so that the entire circumferential surface the roller can be used for grinding. The rotation of the grindstone roller can be done by hand. The roller core 30 is also rotatably mounted and is driven at the appropriate speed either by hand or by a motor. The cutting knives 66 each have two ground contours 70 and two cutting edges 72, as shown in Figure 3, so that each cutting knife can be used twice is.

To replace the cutting edges 72, the cutter bar 64 is around 1800 pivoted. The contour 70 is ground so that the actual cutting edge 72 cuts smoothly, but by touching the outside diameter of the Roller core 30 is not damaged. In any case, the cut is the cutting knife 66 and the feed movement of the cutter bar 64 are coordinated so that the foam through the cutting edge 72 of the cutting knife 66 down to the outer diameter of the roller core is severed. There is indeed a contact between the Cutting knives 66 and the steel tube from which the roller core 30 is made instead, however the cutting edge 72 of the cutting knife is not blunted.

The foam is cut by a rotary movement of the roller core 30 and a feed movement of the cutter bar 64. Since the cutting gap the cutting knife must be matched to the width of the ribs 26 are the knives so polished that a cutting gap of max. 1 mm width is created.

Fig.4 shows a device to the roller core 30 with the thereon located foam tube, the contour of which is shown 38, to heat up so melt the hot-melt adhesive rings between the foam and the roller core.

The device consists of a heating cartridge 74 on which the roller core 30 is pushed on in such a way that it can be heated by the heating cartridge 74. the The heating cartridge 74 is seated in a base 76 which is fastened to a mounting plate 78 is. The base 76 also serves to determine the position of the roller core 30 on the heating cartridge 74 to be determined in the longitudinal direction. Upon actuation of the heating cartridge 64, which is in the is essentially an electrical resistance with a steel jacket, the hot melt adhesive is used liquid and forms a firm bond with the foam. Another possibility, in order to heat up the roller core is to use the roller core itself as an electrical one Switch on resistance in a heating circuit.

L e r s e i t e

Claims (14)

Method and device for producing a foam roller Claims ii A method for producing a foam roller of a rigid one Roller core and foam rings fixed close together on this, d a d u r c h e k e n n -z e i c h n e t that (a) the roll core in the area that is covered with foam, is provided with hot glue that (b) a foam tube is pushed onto the roller core with the cooled hot glue, that (c) the roller core is heated up to the melting point of the hot melt adhesive, and that (d) after the hot melt adhesive has cooled down, cut the foam tube into foam rings and is processed to an even extent. 2. The method according to claim 1, characterized in that the hot-melt adhesive in process step (a) is applied in the form of hot-melt adhesive rings that are inside of the later foam rings. 3. The method according to claim 1 or 2, characterized in that the roller core with the hot glue before pushing on the foam tube is coated with a lubricant. 4. The method according to claim 3, characterized in that silicone used as a liquid lubricant. 5. The method according to claim 3, characterized in that pulverulent Lubricants such as talc or zinc stearate is used. 6. The method according to claim 1, characterized in that the foam tube is drummed after being pushed onto the roller core. 7. The method of claim 1, wherein the roller core consists of an electrically conductive material, characterized in that the roller core acts as a heating resistor is switched and thereby heated up. 8. The method according to claim 1, wherein the roller core is designed as a tube is, characterized in that the roller core from its inside through a heater is heated up. 9. The method according to claim 1, characterized in that the foam after cutting open the foam tube in foam rings to even Scope is processed. 10. The method according to claim 1 or 8, characterized in that editing the outer circumference of the foam tube or the foam rings done by grinding. 11. Apparatus for performing the method according to claim 1 and 8, characterized by a device to the roll core in the area that is covered with the foam, to be provided with hot glue, a device, to push a foam tube onto the roller core with the cooled hot glue, a heating cartridge which can be inserted into the interior of the roller core, and through a Device to put the foam tube in foam rings after the hot melt adhesive has cooled down to be cut up and processed to an even extent. 12. Device for performing the method according to claim 1, characterized through a device to the roller core in the area covered with foam is to be provided with hot glue, a device to the foam tube to slide onto the roller core with the cooled hot glue, a device a knife bar to heat the roller core to the melting point of the hot melt adhesive with a number corresponding to the number of cuts of cutting knives, to cut the foam tube on the roller core into foam rings, and by a device around the foam tube or rings edit to the same extent. 13. Apparatus for performing the method according to claim 1 and 10, characterized by a device to the roll core in the area that is covered with foam, provided with hot glue, a device to to push the foam tube onto the roller core with the cooled hot glue, a device to heat the roller core up to the melting point of the hot melt adhesive, a device to cut the foam tube into foam rings, and through a grindstone roller, around the foam tube or foam rings edit to the same extent. 14. The device according to claim 13, characterized in that the Grinding stone roller consists of grinding stone rings, the inner side surfaces of which are inclined to the grinding stone roller axis and their outer surfaces are cylindrical Form the outer surface of the grinding stone roller, the outer end faces of the end grinding stone roller rings are perpendicular to the grinding stone roller.