DE2318269A1 - GRINDING WHEEL - Google Patents

Description

* »* Ä April 11, 1975

* 6396

2? Τ9Ζ69

Ütyrolit-Schleifniit.telwerke SwarovBki K.G-. 6130 ßchwaz / Austria.

Grinding wheel

The invention relates to a flexible plate grinding wheel, consisting of a carrier disk, one associated with this transition layer, a layer applied to the latter, preferably reticular reinforcement and an actual grinding layer associated therewith.

Ss is once known, such preferably flexible Grinding wheels with frontal edges, mostly more profiled To provide the grinding surface with a fiber board as a carrier * However, this brought with it considerable disadvantages. There are fiberboard door panes of sufficient service life (Layer thickness = several layers) once aup mechanical Reasons too fat, which affects the flexibility of one of the

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unfavorable effects like grinding wheel and are caused naßschliffest only _f. Furthermore, fiber tends to spate ... in layers, which occurs particularly at high circumferential speeds and intermittent loads. However, since, for example, the intermittent loads are frequent in daily operation, the safety of such a grinding wheel is significantly reduced.

As a result one went over to grinding wheels of the above type with a glass fabric or fiber fleece (consisting of gas or organic fibers) as a carrier plate Mistake. Since such disks are generally unprofitable as pure single-grain layer disks, you had to to achieve the necessary strength for the thicker pane, to an inner reinforcement that is in the actual Abrasive grain layer embedded in addition to the carrier plate is to grab.

The disadvantage of such grinding wheels has been found to be the relatively short service life, due to the fact that the grinding surface can only be worn down to the point of internal variation and can therefore be used. The further use stood in the way of chippings in the grinding layer as a result of difficulties in reproducing the grinding layer on the actual carrier plate. Furthermore, for manufacturing reasons, the layer between the carrier plate and the inner reinforcement has to be a few grain layers thick, which causes a reduction in flexibility and the proportion of the total weight of the usable grinding layer, especially with coarse grain sizes. The great K.örnun _r ; In addition, because of the difficulties in imaging mentioned and the relatively low internal strength of the intermediate layer, the explosive speed was low, which meant either a significantly reinforced reinforcement or a

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Loss of security caused. This resulted in particular with grits 46 and coarser and especially with Haßchliffß disks to big problems.

Therefore, the object of the invention is one preferably flexible grinding wheel to create that while avoiding better utilization of the disadvantages mentioned above and has a longer service life with significantly increased security and better flexibility.

This is achieved according to the invention in that üie The grains of the transition layer are finer than the grains of the actual abrasive layer.

Tests carried out with regard to the invention have shown that an optimal operating result is obtained when the mean grain size of the fillers of the transition area is less than 150 ^ * · or a maximum approx. 80 # the grain size of the actual grinding layer amounts to.

It is advantageous if the binder, preferably resin, of the transition area is the same as the binder of the Outer abrasive layer or at least compatible with it and can be processed immediately. For example canoe Look here at potash or thermosetting thermosetting plastics with the same temperature resistance that is sufficient for the grinding process trade, for example phenolic, epoxy, polyester, melamine or similar resins.

The invention is described in detail below with reference to the figure of the drawing, without that shown Execution should be understood in a restrictive sense.

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Likewise, the reference signs cited in the claims mean no restriction; they only serve to make it easier to find related parts in the Figure of the drawing.

The figure of the drawing shows a kept schematic Section through a grinding wheel according to the invention in the direction of the axis of rotation of the wheel.

The grinding wheel according to the figure of the drawing has a carrier plate 1, which must be able to absorb high centrifugal forces, can be produced flexibly and as thinly as possible is. A temperature resistance of more than the grinding temperature is required as further properties, furthermore good binding properties with the actual grinding wheel.

According to the invention, the raw material of the carrier plate a glass fabric or a fleece made of glass or organic Faiern ed. provided, which with appropriate intermediaries (e.g. silanes) and impregnators (e.g. Resolharzenjf is provided. Ea iet of course, that other suitable materials can also be used.

There is a direct connection to the carrier plate a so-called transition area which is formed between this carrier plate 1 and the inner reinforcement 2.

It has proven to be advantageous to use a wide-meshed glass fiber network as the inner reinforcement, as this is the case a particularly good interconnection between the transition layer A and the outer layer B enables. However, it is it goes without saying that the invention is not intended to be limited thereto.

• -ν

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Ie transition area A, the resin of which is the same as that of the Outer layer is B, Rich is now a variety of polishing grains 3 acting as filler material, the middle of which Grit in a fraction (equal to or less than 150) the grain size of the abrasive grains 4 of the outer layer B is.

. It should be added here that in this context the term filler is used in its very general way, that is to say only denotes non-actively binding components of the outer layer or of the transition area. Ss can be proposed, for example, that the grain size in the transition layer A is smaller than

Since the grinding wheel according to the invention Transition layer A and the grinding layer B only Ib differ with regard to the grain size of the abrasive or the filler material, but in bwsug on the resin Form a closed unit, the strength of such a disc is increased by the fact that the fine-grained Mixture of the transition layer A more firmly on the carrier plate 1 and interior 2 sticks and also a higher one has mechanical strength than that of large-grained ones Mixture of the actual SchleifectaJLcht B is the case, as is customary with the previously conventional grinding wheels of this type.

The gate parts of the grinding wheel according to the invention lie in the good binding, soft a tread depth for the profiling of the surface up to the inner lining Permitted, in the higher explosive strength proven by tests and thus security, especially in the case of the JJass cut or after extreme climatic storage conditions

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and furthermore in the possibility of making them as thin as possible and thus flexible with optimal usability. Ea aei mentions that the transition layer A must be a few grain layers of the filler size thick for manufacturing reasons.

Another advantage of the disk according to the invention results from the fact that when using fillers 3 with grinding or polishing properties, the grinding wheel after the actual grinding layer 3 has worn off, as Bollard disc can continue to be used, because of the thin layer thickness on which then of course in the grinding zone omitted central reinforcement can be dispensed with, and this fine-grained layer has sufficient adhesion the Irägerplatte 1 has.

Below is a tabular list of a possible composition of a grinding wheel according to the invention:

1. Carrier plate

2nd transition layer

3. Inner reinforcement 4. Abrasive layer

Glass fabric (Q, 045 g / cm, mesh size approx. 2.5 mm} with thermal curable phenolic resin impregnation (Eesol type), e.g. type 506 from Bock

0.8mm thick, composition

a) Normal corundum grain size 100 wt. 74 * b). Liquid phenolic resin

(e.g. TCF. Deresit SP 531)

c). Phenolic resin in powder form (e.g. VCI Deresit RP 293)

d) cryolite

Glass fabric type 515 / Bock CQ, 045 g / cm, MW approx. 5 km)

with a profiled surface (waffle pattern) 3 mm thick

a) Normal corundum grain size 24

b) Phenolic resin, liquid

c) Phenolic resin in powder form

d) cryolite

14.5 * 7.5 *

79 * 3.5 *

10.5 * 7 *

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! In addition, some safety data (. Discs for 80 b / S Working speed, prescribed blasting speed 150. Jö / S, or comparison of a disc according to the invention with a previously known).

No. Seheibe medium explosion speed

(J mean value from 5 measurements)

! as in the above recipes
1Q saga after manufacture,
atark "flexed ¹¹ 195 m / s

like 1

10 2! Age at 100 ^ _n air-

Efficiency, 40 ⁰ C 185 m / s

like 2

Then 15 minutes of grinding over concave ^ pools (approx. 30? ^ ige

Wear) 178 m / s

Disc with a large-size intermediate layer (same grinding layer,

Grain 24) 160 m / S

Disc like 4

10 saga after production

Storage according to number 2 135 m / S

like 5

Grinding conditions like no.3 124 m / S

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Claims (6)

Patent claims: 1. flexible disc grinding wheel, consisting of a carrier disk, a transition layer connected to this, one applied to the latter, preferably in the form of a network Reinforcement with an actual grinding layer connected to this, characterized in that the Grains (3) of the Übergagsschioht (A); finer than the grains (.4-) are the actual grinding layer (B), 2. Disk according to claim 1, characterized in that the Grain size in the transition layer (A) is less than 150 ". 3. Disc according to claim 1, characterized in that the Binder of the transition area (A) and the abrasive layer (Β), but they can be processed in the same way. 4. Disc according to claim 1, characterized in that the grain size in the transition layer (A) is a maximum of 60 "/> the grain size in the actual grinding layer (B). 5. grinding wheel according to claim 1, characterized in that that at least part of the filler material is active is. 6. grinding wheel according to claim 3, characterized in that that the binder is a Doroplastic plastic.