JPH0590906U - Magnetic rubber, coating masking material, packing material, sludge removing material and anti-slip material - Google Patents

Abstract

(57) [Summary] [Purpose] Has sufficient predetermined suction force for temporary fastening,
Also, to provide a magnetic rubber that does not significantly impair rubber properties such as flexibility. [Structure] The masking sheet 10 which is a magnetic rubber is NB
The R-type rubber 6 is filled with powder particles 7 of strontium-ferrite, and the masking sheet 10 is formed.
The weight fraction of the strontium-ferrite powder particles 7 is 60%.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to magnetic rubber, and more particularly, to a compounding ratio of magnetic powder and rubber material.

[0002]

[Prior Art]

 Magnetic rubber, which has a relatively high attractive force and flexibility not found in sintered magnets, is composed mainly of magnetic powder and a rubber material as a binding material that binds the magnetic powders together. Has been formed. The magnetic powder is often made of a permanent magnet material, which retains its magnetism when magnetized and is easily attracted to a steel plate with a strong force. Typical examples are barium ferrite. , Oxide-based powder magnetic materials such as strontium-ferrite, and metal-based powder magnetic materials such as samarium-cobalt and cerium-cobalt. As the rubber material, NR, NBR, CR, EPDM, etc. are used.

Such a magnetic rubber is widely used in electric products and the like like a gasket of a door part of a refrigerator by utilizing its properties, that is, its relatively high adsorption force and flexibility. However, since magnetic rubber is used as a mixture of magnetic powder (material for permanent magnets) that composes it, the molding density of magnetic rubber is smaller than that of sintered magnets, and the attractive force is also high. It becomes smaller than the force. Therefore, in order to increase the adsorbing power of magnetic rubber, measures such as using magnetic powder with a large coercive force and selecting a rubber material that can be mixed in as much magnetic powder as possible are taken. In a general magnetic rubber, the weight fraction occupied by magnetic powder is about 90%.

[0004]

[Problems to be solved by the device]

 However, since the conventional magnetic rubber is formed for the purpose of increasing its adsorption force, it is convenient when adsorbing and transporting a heavy load, but it is not Since it is inferior in rubber properties and hard, it has a problem that its application is limited and narrow. Further, in the magnetic rubber, the plasticity of the rubber material is sacrificed, and the product shape is limited to a sheet shape by roller rolling or an extruded shape, so that there is a problem that its application is limited.

In view of the above problems, an object of the present invention is to expand the use as a magnetic rubber, and secure a predetermined suction force sufficient for temporary fastening that does not require a strong suction force. However, it is still another object of the present invention to provide a magnetic rubber excellent in flexibility capable of following the shape of the adsorption surface while maintaining the physical properties of the rubber and excellent in plasticity capable of being molded into any shape.

[0006]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, in the magnetic rubber of the present invention, the weight ratio of the magnetic powder in the magnetic rubber is suppressed, and while the sufficient suction force is secured for temporary fixing, etc. This is the ratio of the magnetic powder and the rubber material that does not significantly impair the rubber properties. That is, the means taken in the magnetic rubber according to the present invention is to set the weight fraction of the magnetic powder in the magnetic rubber in the range of 40% to 70%.

[0007] As described above, the magnetic rubber which has a sufficient suction force for temporary fixing and which is not significantly impaired in rubber properties such as flexibility is used as a coating masking member, a packing member, It can be used as a sludge removing member and an anti-slip member.

[0008]

[Action]

 In the magnetic rubber of the present invention having such means, the weight fraction of the magnetic powder in the magnetic rubber is in the range of 40% to 70%. It is possible to improve the rubber properties such as flexibility of the rubber material while having the suction force. FIG. 6 schematically shows changes in the characteristics of the magnetic rubber depending on the weight fraction of the magnetic powder in the magnetic rubber. In FIG. 6, a solid line 91 represents the transition of the adsorption force, which represents the magnetic properties of the magnetic rubber, and a solid line 92 represents the transition of the tensile strength, which represents the rubber properties of the magnetic rubber. The values of the adsorption force and the tensile strength shown in FIG. 6 are arbitrary values. As is clear from this figure, the attractive force and tensile strength of magnetic rubber are in a trade-off relationship. In the magnetic rubber according to the present invention, by adjusting the compounding ratio of the magnetic powder and the rubber material, that is, the weight fraction of the magnetic powder in the magnetic rubber is in the range of 40% to 70%. The rubber properties such as flexibility are improved while ensuring a predetermined adsorption force suitable for the application. Therefore, it is possible to form various members required to have flexibility, such as a masking member for painting, a packing member, a sludge removing member, and an anti-slip member, by using the magnetic rubber having such a structure. Expands. Further, since the magnetic rubber of the present invention is excellent in plasticity, it can be molded into any shape by using a die or the like as well as a sheet shape, so that the application of the magnetic rubber is expanded.

[0009]

【Example】

 Next, embodiments of the present invention will be described with reference to the accompanying drawings.

[First Embodiment] FIG. 1 is a perspective view showing a masking sheet formed using a masking member for coating according to a first embodiment of the present invention. There is. In the figure, a masking sheet 10 is formed by strontium-ferrite powder particles 7 (hereinafter abbreviated as Sr-ferrite 7), which is magnetic powder, filled in an NBR rubber 6. ..

The masking sheet 10 having such a configuration is used for coating various metals such as automobiles. For example, when the body of an automobile is painted in two-tone color, the paint does not adhere to the portion where the masking sheet 10 is adsorbed, so that the paint colors can be easily applied separately. Further, the masking sheet 10 can be partially cut or cut out and used for partial coating.

Next, a method of manufacturing the masking sheet 10 will be described based on the manufacturing process chart shown in FIG. In FIG. 2, first, the magnetic powder (Sr. ferrite 7) and the rubber material (rubber 6) are blended based on the weight fraction of Sr. ferrite 7 set in forming the masking sheet 10 in step ST1. Then, in step ST2, the Sr / ferrite 7 and the rubber 6 are mixed, and in step ST3, kneading (mixing roll) is performed. Here, steps ST2 and ST3 are performed while performing heat treatment. Then, in step ST4, it is extruded after being rolled several times, and in step ST5, it is cut into a predetermined product shape. Here, in the masking sheet 10, in order to maximize its magnetic properties and rubber properties, the particle size of Sr / ferrite 7 is set to about 1.0 μ, and the particle size distribution (dispersion of particle size) ) Is kept as narrow as possible. This is because the magnetic powder having a small particle size and a narrow particle size distribution is uniformly filled in the rubber material during kneading with the rubber material, so that the magnetism of the magnetic rubber is stable and Since it is difficult for a space to form between particles, it also has excellent rubber properties. Further, in the masking sheet 10, in order to improve its magnetism, the axis of easy magnetization of Sr / ferrite 7 is aligned with the magnetization direction in the roller rolling process of step ST4, and the predetermined direction, that is, the adsorption direction of the masking sheet 10 is obtained. Improves magnetism in. As a result, the masking sheet 10 of this example is configured so as not to significantly impair the properties of the magnetic powder Sr / ferrite 7 and the bonding material rubber 6. Therefore, the masking sheet 10 can exert an excellent effect on rubber characteristics such as flexibility while having a predetermined magnetic attraction force.

Here, in the masking sheet 10 of this example, the weight fraction occupied by Sr / ferrite 7 is 60%. The physical properties of rubber of such a masking sheet 10 are compared with the properties of a general magnetic rubber in which the weight fraction of Sr / ferrite is 90%, and the results are shown in Table 1.

[0014]

[Table 1]

As described above, the masking sheet 10 of this example has rubber properties that are far superior to those of general ones in terms of tensile strength, elongation and hardness. On the other hand, although the adsorption power is inferior to that of general ones, when the masking sheet 10 is used, that is, when painting a metal surface of an automobile or the like, it is adsorbed on the painting surface and different painting colors are applied. The suction force required for cleaning is the suction force capable of maintaining the suction state with the coated surface, and therefore the value of this example (14 g) is sufficient. In the masking sheet 10 of this example, the maximum operating temperature is 110 ° C and the minimum operating temperature is -40 ° C.

As described above, since the masking sheet 10 of this example is excellent in rubber properties such as tensile strength, even when the masking sheet 10 is adsorbed on a portion having uneven portions or bent portions on the surface thereof, Since it is possible to bend by following the shape of, it can be adsorbed without a gap, and a high masking effect can be obtained. Here, since the masking sheet 10 bends following the shape of the suction surface to have a large suction area, even a small suction force is substantially a large suction force. Furthermore, since the masking sheet 10 is soft and can be easily cut with ordinary scissors, it is also convenient when partial coating is desired. In addition, after the masking sheet 10 is used, the paint adhered to the surface of the sheet can be easily removed by flexing or twisting the sheet when the paint adheres to the surface of the sheet is dry. No need to wash with solvent.

Second Embodiment FIG. 3 is a usage diagram showing a sealing packing formed by using a packing member according to a second embodiment of the present invention. In this figure, the sealing packing 40 is formed by filling NBR rubber with strontium-ferrite powder particles as in the first embodiment. In this example, the weight fraction of strontium-ferrite, which is magnetic powder, is set to 50%. The sealing packing 40 has a thickness of about 2 mm and is formed in a donut shape having a circular hole 41 in the center, and has four through holes 42 provided at equal intervals on the end side of the circumference thereof. is doing.

The sealing packing 40 having such a configuration is used as a sealing material for a connecting portion between the steel pipes 51. Since the sealing packing 40 has magnetism, it can be easily adsorbed to the connecting portion 51 a of the steel pipe 51 when the steel pipe 51 is connected. Accordingly, the operator may align the through hole 42 of the sealing packing 40 and the bolt insertion hole 52 of the steel pipe 51 to adsorb the sealing packing 40, and the operator may manually attach the sealing packing 40. Since there is no need to hold it down or temporarily fix it with tape, work efficiency is good. Here, the magnetism required for the sealing packing 40 may be a temporary magnetism during the connection work of the steel pipes 51, and a small attraction force may be used. Therefore, the weight fraction of the rubber in the sealing packing 40, which is a magnetic rubber, can be increased (the weight fraction of the magnetic powder can be reduced), so that the sealing packing 40 is soft and excellent in flexibility. It is possible to obtain a good effect as a sealing material for the connecting portion of the steel pipe 51.

The packing member formed with the same mixing ratio of the magnetic powder and the rubber material as the sealing packing 40 of this example is also used for a door set such as a switchboard. can do. Further, it can be used as a gasket for a refrigerator, an accordion door suction plate, or the like.

[Third Embodiment] FIG. 4 is a usage diagram showing a slag removing sheet formed using a sludge removing member according to a third embodiment of the present invention. In the figure, strontium ferrite is used as the magnetic powder in the sludge removing sheet 60, and its weight fraction is 70%. As the rubber material, NBR which has oil resistance and is widely used as an industrial rubber is used.

The sludge removing sheet 60 of this example is used for the purpose of removing the sludge 63 in the hydraulic tank. The sludge 63 adsorbed on the sludge removing sheet 60 is easily slid by, for example, repeatedly vibrating the sludge removing sheet 60 in the direction of arrow A, or twisting it like a dust cloth. 60 can be detached. As described above, the sludge removing sheet 60 of this embodiment can remove the adsorbed sludge 63 without demagnetizing or demagnetizing the sludge 63, so that the sludge 63 can be easily removed and recovered, and the work efficiency is good. ..

[Embodiment 4] FIG. 5 is a use mode diagram showing an anti-slip tape formed using an anti-slip member according to an embodiment 4 of the present invention. In this figure, the weight fraction of the magnetic powder strontium ferrite in the anti-slip tape 70 is set to 50%. The anti-slip tape 70 is formed in a strip shape having a thickness of about 1 mm.

The anti-slip tape 70 having such a configuration is wound around a grip portion 73 of a tool such as a wrench 72 and used for the purpose of preventing the grip portion 73 from slipping. In the anti-slip tape 70, the weight fraction of the magnetic powder is 50%, the rubber property is high and the flexibility is excellent, and the anti-slip tape 70 is soft and can be easily wound around the grip portion 73.

Since the length of the anti-slip tape 70 is formed to be larger than the outer peripheral dimension of the grip portion 73, the anti-slip tape 70 is wound around the grip portion 73 in double or triple layers, and is attracted to the grip portion 73 while being overlapped and wound. The slip-proof tapes 70 themselves stick to each other and are fixed to the wrench 72. As described above, the anti-slip tape 70 of this example can be fixed simply by winding it around the grip portion 73 of the wrench 72, and it is easy to attach / detach and is very convenient. Further, the anti-slip tape 70 has an advantage that it can be used in any environment because it does not affect the adsorption action even when the grip portion 73 is wet with water or oil. Further, the anti-slip tape 70 also serves as a cushion for the grip portion 73 and also has an effect of softening the feeling of gripping.

As described above, in the magnetic rubber according to the present invention, the weight fraction of the magnetic powder in the magnetic rubber is in the range of 40% to 70%. Therefore, in magnetic rubber, the attractive force, which is a magnetic property, can be maintained at a level sufficient for operations such as temporary fastening, and the rubber properties such as flexibility can be improved, and its application can be expanded. It has become possible. In addition, since magnetic rubber contains a large amount of rubber material, it does not easily crack even when used for a long period of time and can be used stably.

In the first to fourth embodiments, the magnetic rubber formed in the shape of a sheet has been described, but a molded product having various shapes can be used by using a mold or the like. The magnetic powder used for the magnetic rubber is not limited to strontium-ferrite, but may be, for example, barium-ferrite, neodymium-iron-boron, samarium-cobalt or cerium-cobalt. Of course.

[0027]

[Effect of the device]

 As described above, the magnetic rubber according to the present invention is characterized in that the weight fraction of the magnetic powder in the magnetic rubber is in the range of 40% to 70%. Therefore, it is possible to obtain a magnetic rubber having an attractive force that is a magnetic property, which is sufficient for temporary fixing and is excellent in rubber properties such as flexibility. As a result, the magnetic rubber can be used for various members requiring flexibility, such as a masking member for painting, a packing member, a sludge removing member, and an anti-slip member, and its application is expanded. In addition, since it has excellent plasticity, it can be molded into any shape by using a metal mold or the like, not to mention a sheet shape, thus expanding the applications of magnetic rubber.

[Brief description of drawings]

FIG. 1 is a perspective view showing a masking sheet according to a first embodiment of the present invention.

FIG. 2 is a manufacturing process drawing of the masking sheet.

FIG. 3 is a usage diagram showing a sealing packing according to a second embodiment of the present invention.

FIG. 4 is a usage diagram showing a sludge removing sheet according to a third embodiment of the present invention.

FIG. 5 is a view showing the manner of use of the anti-slip tape according to Example 4 of the present invention.

FIG. 6 is a graph diagram schematically showing changes in adsorption force and tensile strength in terms of weight fraction of magnetic powder in magnetic rubber.

[Explanation of symbols]

 6 ... Rubber 7 ... Sr / ferrite 10 ... Masking sheet 40 ... Sealing packing 60 ... Sludge removal sheet 70 ... Anti-slip tape

Claims (5)

[Scope of utility model registration request] 1. A magnetic rubber formed mainly of magnetic powder and a rubber material, wherein the weight fraction of the magnetic powder in the magnetic rubber is in the range of 40% to 70%. Magnetic rubber characterized by. 2. A masking member for coating, characterized in that the magnetic rubber defined in claim 1 is used. 3. A packing member comprising the magnetic rubber defined in claim 1. 4. A sludge removing member comprising the magnetic rubber defined in claim 1. 5. An anti-slip member comprising the magnetic rubber defined in claim 1.