Method of producing a cleaning device

Abstract

METHOD OF MANUFACTURING A CLEANING DEVICE The present invention is a method of producing a structurally unified cleaning device (300) comprising a cleaning member (301) and a holding member (303). The steps to produce the 5 cleaning device involve providing a holding member (303) in a tool, arranging (201) a cleaning member (301) on the holding member (303) in the tool, forming (201) the cleaning member (301) and the holding member (303) into a structurally unified cleaning device (300), curing (203) the structurally unified cleaning device (300) to stabilize and solidify the interface between the cleaning member (301) and the holding member (303), trimming (205) the 0 structurally unified cleaning device (300) to the desired physical requirements, thereby producing a final cleaning device (300), inspecting (207) the final cleaning device for visual and quality defects, and packing (209) the approved final cleaning device for storage and shipment. 5 FIG. 2

Description

[0001] METHOD OF PRODUCING A CLEANING DEVICE

[0002] FIELD OF INVENTION

[0003] The present invention relates to a cleaning device. More particularly, the invention relates to a method of producing a cleaning device.

[0004] BACKGROUND OF THE INVENTION

[0005] A conventional process for producing a cleaning device starts with the knitting of a filament body consisting of the warp and weft. The knitted filament body is glued at the stitching yam. After the glueing process, the filament body is cured at approximately 100 °C. Next, the knitted filament body is measured to the desired length and cut into strips. The knitted filament strips are then overmolded using the injection molding. The filament strips are then trimmed to the desired height. Finally, the filament strips are inspected and packed for storage and shipment.

[0006] Although long established and well known, the current process steps suffer from certain quality and reliability issues. For example, flash is produced during injection molding. Flash is excess plastic that forms on the surface of the molded parts. This is a potential reliability problem for cleaning devices because the flash can spread along the filaments. The plastic compound of the flash tends to harden the filaments, reducing its deflection capability and increasing its brittleness. Ultimately the filaments would tend to break off with prolonged usage affecting the effectiveness of the cleaning device.

[0007] While the primary reason for gluing the stitching yam is to increase the binding strength between the weft and warp, the glue also acts as a barrier to prevent the injection molding flash from spreading up the filament during the subsequent injection molding process. However, the gluing process introduces other quality problems such as challenging process setup conditions, constant cleaning due to staining and smearing on the equipment, and limited shelflife leading to waste.

[0008] It is thus highly advantageous if the elimination of the gluing and the injection molding process can be accomplished without compromising the present quality and reliability of the cleaning device. The present invention to produce cleaning devices replaces the filament knitting, gluing, and injection molding process steps. The elimination of the aforementioned processes results in a number of advantageous aspects.

[0009] In an advantageous aspect of the present invention, the overall number of process steps to produce a cleaning device is reduced, thereby reducing the manufacturing cycle time.

[0010] In another advantageous aspect of the present invention, the introduction of substitute processes has either eliminated or decreased the use of material such as glue and injection molding plastic pellets, thereby simplifying the Bill Of Material (BOM) and subsequently reducing waste.

[0011] In another advantageous aspect of the present invention, the type and quantity of equipment to produce cleaning devices is reduced, thereby requiring less labour, freeing up factory space, and reducing energy consumption.

[0012] Finally, another advantageous aspect of the present invention is the enabling of greater flexibility to produce various configurations of cleaning devices, thereby increasing the potential to serve various markets.

[0013] SUMMARY OF THE INVENTION

[0014] The present invention relates to a method of producing a structurally unified cleaning device comprising a cleaning member and a holding member comprising the steps of: providing a holding member in a tool; arranging a cleaning member on the holding member in the tool; forming the cleaning member and the holding member into a structurally unified cleaning device; curing the structurally unified cleaning device to stabilize and solidify the interface between the cleaning member and the holding member; trimming the structurally unified cleaning device to the desired physical requirements, thereby producing a final cleaning device; inspecting the final cleaning device for visual and quality defects; and packing the approved final cleaning device for storage and shipment.

[0015] BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Other objects, features, and advantages of the invention will be apparent from the following description when read with reference to the accompanying drawings. In the drawings, wherein like reference numerals denote corresponding parts throughout the several views:

[0017] Fig. 1 is a comparison between the conventional and new method of producing the cleaning device.

[0018] Fig. 2 shows the process steps of the new method for producing the cleaning device.

[0019] Fig. 3a shows a side view of an embodiment of the cleaning device before forming.

[0020] Fig. 3b shows a side view of an embodiment of the cleaning device after forming.

[0021] Fig. 4a shows a side view of a first embodiment of the cleaning device.

[0022] Fig. 4b shows a side view of a second embodiment of the cleaning device.

[0023] Fig. 4c shows a side view of a third embodiment of the cleaning device.

[0024] Fig. 5 a shows a side view of a fourth embodiment of the cleaning device.

[0025] Fig. 6a shows a front view of a first embodiment of the cleaning device.

[0026] Fig. 6b shows a front view of a second embodiment of the cleaning device.

[0027] Fig. 6c shows a front view of a third embodiment of the cleaning device.

[0028] Fig. 6d shows a front view of a fourth embodiment of the cleaning device.

[0029] DETAILED DESCRIPTION OF THE INVENTION

[0030] The present invention relates to a method of producing a structurally unified cleaning device comprising a cleaning member and a holding member.

[0031] Referring to Fig. 1, the conventional process steps to produce a cleaning device is shown on the left (101). The first step is filament knitting (102) where the weft and warp yams are knitted into filament strips. The next step is gluing (103) to increase the binding strength of the weft and warp stitching. The following process is where the knitted filament strips are placed in a chamber set to approximately 100 °C to for curing (104). After the cure, the filament strips are cut to the required length (105), and then a section of the knitted strip is overmolded at an injection molding (106) station. The subsequent steps are the trimming (107) of the filaments to the required height, inspection (108) for defects and finally the packing (109) of accepted cleaning devices for storage and shipment.

[0032] There are a total of 8 process steps in the conventional flow to produce a cleaning device. The conventional flow requires a large footprint due to the equipment required such as the knitting machines, gluing stations and injection molding presses.

[0033] The complex nature of some of these process steps such as the gluing (103) and injection molding (106) frequently result in irregular outcomes and subsequent product defects unless the processes are closely and continuously monitored. In addition, the introduction of new product configurations requires extensive experimentation and data collection to obtain optimized process settings such as curing period and temperature, and final mold cavity designs. The current process therefore provides an opportunity for shorter process cycle-time, better yields and less costly manufacturing costs.

[0034] The present method as shown in Fig. 1 (111) eliminates the most problematic process steps and has fewer processing steps. The motivation for the new invention was to improve the production method without compromising the quality and reliability of the current cleaning devices while achieving improved yields, less expensive production costs and greater flexibility for new product introductions. Referring to the flow labelled 111 in Fig. 1, the new method starts with the arrangement of a cleaning member relative to a holding member in the process tool (112). Once the configuration is done, the cleaning member and the holding member are formed into a structurally unified cleaning device (112). The cleaning device is then subjected to the same process steps as the conventional method, namely curing (113), trimming (114), inspection (115) and packing (116).

[0035] With the new method (111), there are a total of 5 production steps. By removing the aforementioned filament knitting (102), gluing (103), and injection molding (106) processes, the present invent produces multiple technical and subsequently commercial benefits.

[0036] Referring to Fig. 2 and Fig. 3a, the new invention is a method of producing a cleaning device that starts with a holding member (303) placed in a forming process tool (201), and the arrangement (201) of a cleaning member (301) relative to the holding member (303) in the said tool.

[0037] In an embodiment of the cleaning device (300), the cleaning member (301) is a plurality of filaments made from suitable material and arranged in a desired configuration.

[0038] In another embodiment of the cleaning device (300), the cleaning device (301) is a plurality of blade elements made from suitable material and arranged in a desired configuration.

[0039] In another embodiment of the cleaning device (300), the cleaning device (301) is a combination of filaments and blade elements made from suitable material and arranged in a desired configuration.

[0040] Referring to Fig. 2 and Fig. 3b, when the desired configuration of the cleaning product is achieved, the process tool is enabled for forming (201) a structurally unified cleaning device (300). Heat is introduced in the process tool to induce a chemical and mechanical bonding between the cleaning member (301) and the holding member (303. The chemical and mechanical bonding produces an interfacial layer (305) that binds the cleaning member (301) to the holding member (305) in a structurally unified cleaning device (300). The forming process, depending on the material composition and configuration of the final cleaning device (300), is accomplished at a temperature range of 50 °C to 300 °C.

[0041] In an embodiment of the forming process, the interfacial layer (305) between the cleaning member (301) and the holding member (303) is formed with contact heating.

[0042] In another embodiment of the forming process, the interfacial layer (305) between the cleaning member (301) and the holding member (303) is formed with non-contact heating.

[0043] There are difficulties to the arrangement and forming process (201) that the person of skill in the art needs to address. The first challenge is to ensure the retrieval and placement of the cleaning member (301) on the holding member (303) does not deviate from the required final configuration of the cleaning member (300). A second challenge is to optimize the process settings for the forming tool to ensure the chemical and mechanical bonding at the interfacial layer (305) is strong enough to meet the required quality and reliability specifications. For example, a cleaning device may have to withstand high frictional and rotational forces during its application without the cleaning member (301) being dislodged from the holding member (303).

[0044] In order to ensure the chemical and mechanical bonding on the interfacial layer is achieved, a curing process (Fig. 2, 205) is required. The structurally unified cleaning device (300) is a placed in chamber for a certain period of time and at a specified temperature to stabilize and solidify the interface (305) between the cleaning member (301) and the holding member (303).

[0045] The optimized curing time and temperature is dependent on, among other factors, on the type of material and the desired configuration of the cleaning device (300). These process settings are to be determined empirically after a series of experiments.

[0046] In an embodiment of the curing process, the curing period is between 60 s to 3600 s depending on the material composition and configuration of the cleaning device.

[0047] In another embodiment of the curing process, the curing temperature is between 30 °C to 100 °C depending on the material composition and configuration of the cleaning device. In an embodiment of the final cleaning device (300), to ensure the bonding strength is sufficient for the cleaning application, a lower specification limit of 30 N is required for the retention of the cleaning member (301) in the holding member (303). Post-curing (205), samples are removed from the batch for retention strength testing for quality assurance purposes. The retention strength of the cleaning member (301) to the holding member (303) is at least 30 N for the cleaning device (300) to be accepted.

[0048] Referring to Fig. 2, once the newly introduced process steps of arranging and forming (201), and the critical process step of curing (203), is completed, the subsequent trimming (205), inspection (207), and packing (209) will be similar to the present conventional process.

[0049] Among the benefits of the streamlined and flexible new method (Fig. 1, 111) is the potential to introduce various cleaning devices with different configurations. These configurations, would have posed tremendous technical and economic challenges previously. The new method is an opportunity to extend the market for the cleaning devices beyond the present use cases. Referring to Fig. 4a, an embodiment of final cleaning device is a continuous filament strip (401) at a right angle to the longitudinal axis of the holding member (403).

[0050] Referring to Fig. 4b, an embodiment of final cleaning device is a continuous filament strip (411) at an oblique angle to the longitudinal axis of the holding member (413).

[0051] Referring to Fig. 4c, an embodiment of final cleaning device is a plurality of filament strips (421) with gaps (425) in-between.

[0052] Referring to Fig. 5a, an embodiment of final cleaning device is a plurality of filament strips (501) interspersed with a plurality of blade elements (503).

[0053] Referring to Fig. 6a, from the front-view (Fig. 3b, 309) of the holding member (603), the filament strip can be arranged and formed at a right angle (601) to the vertical axis of the holding member (603).

[0054] Referring to Fig. 6b, from the front-view (Fig. 3b, 309) of the holding member (613), the filament strip can be arranged and formed at an oblique angle (611) to the vertical axis of the holding member (613). Referring to Fig. 6c, from the front-view (Fig. 3b, 309) of the holding member (625), the filament strip (621) can be arranged and formed in parallel with the blade elements (623). Referring to Fig. 6d, from the front-view (Fig. 3b, 309) of the holding member (635), the filament strip (621) can be arranged and formed in between two blade elements (631 and 633).

[0055] Although the embodiments herein are described with various specific embodiments, it will be obvious for a person skilled in the art to practice the invention with modifications. However, all such modifications are deemed to be within the scope of the claims. As will be readily apparent to those skilled in the art, the present invention may easily be produced in other specific forms without departing from its essential characteristics. The present embodiments are therefore, to be considered as merely illustrative and not restrictive, the scope of the invention being indicated by the claims rather than the foregoing description, and all changes which come within therefore intended to be embraced therein.

Claims

CLAIMS1. A method of producing a cleaning device, the method comprising: providing a holding member (303) in a tool; arranging (201) a cleaning member (301) on the holding member (303) in the tool; forming (201) the cleaning member (301) and the holding member (303) into a structurally unified cleaning device (300); curing (205) the structurally unified cleaning device (300) to stabilize and solidify the interface between the cleaning member (301) and the holding member (303); trimming (205) the structurally unified cleaning device (300) to the desired physical requirements, thereby producing a final cleaning device (300); inspecting (207) the final cleaning device for visual and quality defects; and packing (209) the approved final cleaning device (300) for storage and shipment.

2. The method as claimed in claim 1 wherein the cleaning member (301) comprises aplurality of filaments (401, 411, 421).

3. The method as claimed in claim 2 wherein the filaments are arranged in a desired configuration (401, 411, 421, 501, 601, 611, 621, 631, 633).

4. The method as claimed in claim 1 wherein the cleaning member (301) comprises aplurality of blade elements (503).

5. The method as claimed in claim 4 wherein the blade elements are arranged in a desired configuration (501, 623, 632).

6. The method as claimed in claim 1 wherein the cleaning member comprises a combination of filaments and blade element (Fig. 5a, Fig. 6c, Fig. 6d).

7. The method as claimed in claim 6 wherein the cleaning member are arranged in a desired configuration (Fig. 5a, Fig. 6c, Fig. 6d).

8. The method as claimed in claim 1 wherein the forming (205) process, depending on the material composition and configuration of the final cleaning device (300), is accomplished at a temperature range of 50 °C to 300 °C, thereby connecting the cleaning member (301) and the holding member (303) at an interfacial layer (305).

9. The method as claimed in claim 8 wherein the interfacial layer (305) between the cleaning member (301) and the holding member (303) is formed with contact heating.

10. The method as claimed in claim 8 wherein the interfacial layer (305) between the cleaning member (301) and the holding member (303) is formed with non-contact heating.

11. The method as claimed in claim 1 wherein the curing (205) process period is between 60 s to 3600 s depending on the material composition and configuration of the cleaning device (300).

12. The method as claimed in claim 1 wherein the curing (205) process temperature is between 30 °C to 100 °C depending on the material composition and configuration of the cleaning device (300).

13. The method as claimed in claim 11 wherein the retention strength of the cleaning member (301) to the holding member (303) is at least 30 N.

Images