DE3049878A1 - RUBBER SHEET FOR TURNTABLE - Google Patents

Description

Rubber plate for a turntable, characterized in that it is a vulcanized molded body made of a rubber mixture, which has a hardness within the range of 30, measured with a rubber hardness tester of the Α type, to 15, measured with a rubber hardness tester of the F ~ Type, and has an impact resilience of not less than 40 % . This rubber plate effectively prevents the sound quality of reproduced sounds (tones) from deteriorating due to howling or external vibrations, and enables the realistic reproduction of original sounds.

230609/0038

G 52 703

Applicant: Hohyu Rubber Co «, Ltd.

No. 720-1, Toyoshima Minami 1-chome, Ikeda-shi, Osaka 563, Japan

Writing rubber plate for a turntable

Technical field of application

The invention relates to a rubber plate for the turntable of a record player.

Technical background

The rubber plate for a turntable is used to isolate a record from the acoustic output of a record Loudspeaker, to vibrations of a turntable itself and the like · to thereby prevent howling and the Deterioration of the SN ratio as a result of vibrations to prevent the record itself during its playback. The howling is a kind of oscillation phenomenon that can be attributed to is the effect of the acoustic output of a loudspeaker on a recording and it occurs as a result of the transmission of vibrations from the loudspeaker to the turntable ι

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j through the floor or rack on which the turntable is placed

is, or as a result of direct vibration of the turntable

caused by the sound pressure from the loudspeaker.

Needless to say, when the howling occurs, normal playback of the record cannot be performed. Even if there is no howling, the frequency response of the recording output would change and local resonance and the like would be caused by external vibrations, and the sound quality of the reproduced sounds would be increased by the increase in the distortion factor, the deterioration of the compensation process and the like be adversely affected. The most common rumbling occurs as a result of external vibrations from the floor or the frame on which the turntable is placed.

The majority of these external vibrations are of the order of magnitude of not more than 100 Hz and in particular includes a component with a very low frequency of otv / a 5 to 10 Hz. Around the howl To effectively prevent it, a rubber plate for a turntable having excellent vibration absorbing properties would be desired has a very low frequency in this area.

The conventional rubber plates for turntables that are manufactured are made of natural rubber, isoprene rubber, chloroprene rubber, butyl rubber, Styrene-butadiene rubber, butadiene rubber, silicone rubber or urethane rubber or mixtures thereof, however, have poorer vibration-absorbing properties, in particular in the very low frequency range on and are therefore unable to protect the sound quality of the reproduced tones (sounds) against deterioration as a result effective protection against howling or external vibrations.

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Description of the invention

The inventor has now extensive and careful research "ujt developing a rubber plate for a turntable carried out by AISS sound quality of the reproduced sounds (sounds) as a result of howling pdor external vibration is getting worse and playback vpn tones (Klöngen) which effectively prevents, which are just as realistic as the original tones themselves (such as human voices themselves). A result has been found that the above-described goal can be achieved with a rubber sheet, which is a sheet-shaped vulcanized molded body of a rubber odor, the one Heard within the range of 30, measured with an A-type rubber hardness tester, to 15, measured with a PU-type rubber hardness tester, and has an impact resilience of not less than 40 % . The above is for the rubber »Type A hardness testing device around a rubber hardness test device, wip ßi © ira JiS K 6301 <-1969 is provided. The F "-type rubber hardness test device is an Asker Fx-type rubber hardness test device manufactured by Kobunshi Keiki Mfß, Co." Lid *, which is mainly used for measuring the hardness of foam rubber, urethane foam or the like . is used. Although ps this is calibrated to a solid rubber, a part of the vplkenisierten rubber according to the present invention is too low Stopped for the measurement by means of the Gummihärtetestvorriehtung from Α-type diet pure measurement of the hardness of conventional solid rubber used · will therefore be the lower limit of the hardness of the vulcanized rubber of the present invention is defined by

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the hardness value as determined by the rubber hardness tester from F-type is measured.

An average hardness between the measuring range of the Α-type rubber hardness tester and that of the F-type rubber hardness tester can be measured with a C-type rubber hardness tester. The C-type rubber hardness tester used here is such as this one in the Society of Rubber Industry Japan Standard SRIS-OlOl is provided and for measuring such mean hardnesses between the Measuring ranges of the rubber hardness testers Α-type and from F-type is used. The C-type rubber hardness tester is mostly used to measure the hardness of a sponge, of soft rubber or the like. As the C-type rubber hardness tester, the Asker C-type rubber hardness tester manufactured by Kobunshi Seiki Mfg. Co., Ltd. manufactured will.

The hardness of the vulcanized rubber of the present invention can be determined with the Α-type rubber hardness tester, the C-type rubber hardness tester, and the F-type rubber hardness tester if measurement is possible with any of these rubber hardness testers. However, when a hardness measured with the Α-type rubber hardness tester is not more than 1, it is preferable to measure the hardness with either the C-type rubber hardness tester or the F-type rubber hardness tester because the measurement with the rubber hardness tester from Α-type is accompanied by increased errors. Correspondingly, if a

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Heard measured with the C-type rubber hearing tester, is not more than 1 °, it is preferred to use the hardness with the F-type rubber hearing tester to measure If a hardness, measured by the C-type rubber hardness tester is not less than 99 °, it is further preferable to measure the hardness with of the Α-type rubber hardness tester. Correspondingly, if there is a hardness, it is measured with the F-type rubber hardness tester, not less than 99 , it is preferable to test the hardness with the C-type rubber hardness tester or with the rubber hardness tester from Measure Α type. The hardness values obtained with the Α-type rubber hardness tester, with the C-type rubber hardness tester and measured with the F-type rubber hardness tester, are hereinafter referred to as Α hardness, C hardness and F hardness.

The vulcanized rubber of the present invention has a hardness of not more than 30, preferably not more than 20, in terms of Α hardness, to not less than 15, preferably not less than 30 , in terms of F ~ Hurt, and an impact resilience of not less than 40 %, preferably not less than 50 %, particularly preferably 60 to 95 % , * Such a vulcanized rubber is a new rubber material which has not been known heretofore · That is, in the case of conventional vulcanized rubbers those with a hardness of no more than about 30 ° have an impact resilience of less than about 40 % ; and those with an impact resilience of no less than about 40 % have a hardness greater than about 30 °. It is well known that the resilience of impact

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vulcanized rubber with decreasing hardness decreases · The physical properties of the cured rubber according to the invention, ie a Α hardness of not more than 30, preferably not more than 20 and an impact resilience of not less than 40%, preferably not less than 50%, particularly preferably from 60 to 95 %, are definitely outside the previously common concept.

The rubber plate for a turntable made of the above-described novel vulcanized rubber of the present invention has a remarkable effect that it has excellent vibration absorbing properties especially in the very low frequency range ₍ and prevents the sound quality of reproduced sounds (sounds) from being wailed or That is, the rubber sheet effectively absorbs and shields the vibrations of the above-mentioned very low frequencies, especially those not exceeding 10 Hz, and isolates a record from these vibrations, so that howling occurs effectively This is prevented and there are no dangers caused by these vibrations, such as modulation of the pickup outputs. Accordingly, the highest notes in the soprano in particular can be reproduced as they are female vowel sounds and can also be excellent in the bass range reproduced tones (sounds) can be achieved. The listeners can therefore enjoy listening to a record with a richer presence.

The vulcanized rubber of the present invention must have a hardness within

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the range from a Α hardness of not more than 30, preferably not more than 20, to an F hardness of not less than 15, preferably not less than 30, and an impact resilience of not less than 40 %, preferably not less than 50 %, particularly preferably from 60 to 95 % . Only when the hardness and impact resilience are within the above ranges can the vulcanized rubber exhibit excellent vibration absorbing properties, particularly in the very low frequency range, and prevent the sound quality of reproduced sounds from being deteriorated by howling or external vibrations below Maintaining the general properties as a rubber sheet for a turntable · When the hardness is higher than the above range and when the impact resilience is lower than the above range, the vibration & absorption properties become poor, particularly in the very low frequency range · Further, the property goes of the vulcanized rubber of the present invention to be soft and elastic like baby skin, which is one of the most significant features of the vulcanized rubber of the present invention, has been lost. As a result, the rubber plate does not come into close contact with the record or the turntable, and it does not ensure a breathing phenomenon above and below (this will be described in more detail below). If both the hardness and the impact resilience are below the above ranges, the rubber plate has poor self-supporting properties and cannot support the weight of a record, a cartridge and a tone arm, with the result that its original shape is not retained can the

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Projections provided on the rubber sheet as described below are deformed and flat so that the Contact surface area between the rubber sheet and a Record or a plaitentel server is enlarged and the reproduced Tones (sounds) tend to become heavy * It is therefore impossible to have both clear and even original tones ■ reproduce in the high frequency range as well as in the bass range «

The rubber sheet according to the invention can depending on its physical properties, mainly on the basis of Subdivision into the following three categories:

(i) A rubber sheet having a hardness of more than 15 to not more than 30 in Α hardness and an impact resilience of not less than 50 %, particularly from 65 to 95 %. The rubber sheet of this category allows in particular the reproduction of resounding tones. Therefore, for example, the sounding notes of a pipe organ or the like can be reproduced as they are, and the highest notes of the soprano of female vocalists can be beautifully reproduced.

(il) A rubber sheet with a hardness of 1 to 15, preferably of 2 ° to 7 °, in the Α hardness and an impact elasticity of 40 to 90 %, preferably from 50 to 95 %, particularly preferably from 60 to 95 % The rubber sheet of this category has the advantages of the rubber sheets belonging to both category (i) and category (III) discussed below .

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(ill) A rubber sheet with a hearing of less than 1 in Α hardness to not less than 15 ", preferably not less than 30 ° _; in the F hardness and an impact resilience of not less than 40%, particularly 50 to 95 % _o The rubber sheet of this category prevents the club more effectively and allows better tones (sounds) to be reproduced in the very low frequency range.

It is also desirable that in addition to those defined above physical properties of the vulcanized according to the invention

Rubber has a tensile strength of 0.1 to TOO kg / cm, preferably

from 1 to 50 kg / cm, an elongation of 50 to 1000 %, preferably from 200 to 1000 %, and a specific gravity of 0.8 to 1.3, preferably from 0.89 to 1.05 Tensile strength is below the above range, the rubber sheet has poor self-supporting properties, and it becomes brittle and is easily broken when a small tensile force is applied. If, on the other hand, it lies above the above range, the rubber plate loses its flexibility and no longer comes into close contact with the record or the turntable. If the expansion is below the above range, breathing is difficult, as stated above. On the other hand, if the elongation is below the above range, there is a risk that the rubber sheet will be stretched to the maximum and sag. If the specific gravity is above the above range, an excessive load is applied to a drive motor for the turntable provided that the average thickness of the rubber plate is more than 2 mm, thereby increasing vibratory vibration of the motor. If, on the other hand, the specific »,

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Weight is below the above range, it becomes impossible to add fillers to the rubber composition, so that it is difficult to manufacture a cummi sheet with a minimum of self-supporting properties.

Preferred physical constants for the guru plates of Categories (I) to (ill) defined above are the following:

Category (i)

2 2

Tensile strength: 1 to 100 kg / cm, especially 5 to 50 kg / cm.

Elongation: 100 to 1000 %, in particular 200 to 1000 %. spec. Weight: 0.89 to 1.05

Category (II)

2 2

Tensile strength: 1 to 50 kg / cm, especially 3 to 50 kg / cm. Elongation: 100 to 1000 %, preferably 120 to 1000 % and

especially 200 to 1000 %. spec. Weight: 0.89 to 1.05, especially 0.93 to 1.05 »

Category (Hl)

2

Tensile strength: 0.1 to 50 kg / cm, especially 0.1 to 20 kg / cm

Elongation: 100 to 1000 %, in particular 200 to 1000 %,

special weight: 0.89 to 1.05.

The vulcanized rubber with the specifics given above physical constants can be produced by vulcanizing a rubber compound which contains (A) 100 parts (parts by weight, this also applies to the following information) of a gumra component, (ß) 1 to 2000 parts, preferably 5 to 2000 parts, particularly preferably 100 to 1500 parts, of a factice and (C) 20 to 2000 parts, preferably 50 to 2000 parts, especially

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preferably 200 to 1500 parts, of a plasticizer. The rubber compound obtained by adding such large amounts of a factice and a plasticizer to a rubber component is a new rubber composition. By merely vulcanizing such a new rubber composition (rubber compound), a special vulcanized rubber having a hardness of not more than 30, especially not more than 20 ,, as Α hardness, and an impact resilience of not less than 40 %, preferably not less than 50 %, particularly preferably from 60 to 95 % _t are obtained.

The rubber component (A) is not subject to any special restrictions.Examples of this are rubber components / which consist predominantly of one or more representatives from the group polynorbornone, natural rubber, isoprene guinmi, chloroprene gourami, styrene-8utadiene rubber, butadiene rubber, buty! Rubber, ethylene propylene Rubber, ethylene propylene diene rubber, nitrile rubber, acrylic rubber, urethane rubber, chlorinated polyethylene, chlorosulfonated polyethylene, epichlorohydrin rubber, polysulfide rubber, silicone rubber and rubber these rubber components are in the form of a solid (powder, pellet, block, plate and the like) or in the form of a liquid (liquid rubber, latex and the like). Among these components is a rubber component which consists of polynorbornene as the predominant component , particularly preferred according to the invention. In this case, it is desirable that the proportion of the polynorbornene is not less than 50 5? (% By weight , this also applies to the following information), preferably not less than 65 %, based on the

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in the

Total weight of the rubber component, is. As polynorbornene are preferably those with an average molecular weight of about 10 to about 5 10, particularly preferably of about 2 10 to about 3 χ 10 are used.

The factice used as component (B) includes any kinds of various factices, such as white factice, black factice, amber factice, and blue factice, which are obtainable by vulcanizing a variety of vegetable oils including flaxseed oil, rapeseed oil, soybean oil, sesaro oil, tung oil and castor oil, using sulfur or Sulfur chloride. These factices can be used alone or in admixture with one another. The factice made by vulcanizing rapeseed oil is the most beneficial.

The plasticizer used as component (C) includes oils, plasticizers and other agents having a calibrating activity » The oils include aromatic oils, naphthenic oils, paraffin oils, vegetable oil and animal oils and the like. Usually can be used as filling oils (plasticizer oil, process oil and the like) for rubbers. The vegetable oils and animal oils mentioned above include, for example, castor oil, rapeseed oil, Flaxseed oil, whale oil, fish oil and the like. As plasticizers those with a high plasticizing power among the plasticizers commonly used as plasticizers for rubbers are used. Suitable examples are dibutyl phthalate, pioctyl phthalate and dioctyl sebacate. Other plasticizers include liquid gums. The plasticizers mentioned above can be used alone or as a mixture, usually

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an oil alone or in admixture with a plasticizer is preferred.

The above rubber composition (Gurntni mixture) can in addition, suitable customary rubber additives, such as fillers such as carbon black and zinc oxide, coloring agents, lubricants (glidants) such as stearic acid and antioxidants, up to may be added in addition to components (A) to (C) to such an extent as to be the physical ones discussed above Do not affect properties

Preferred rubber compounds for the rubber sheets of the categories (i) to (III) are as follows:

Category (i) Component (A) 100 parts Component (B) 1 to 1500 parts, preferably 5 to 1000 parts

and particularly preferably 100 to 1000 parts of component (C) 20 to 1500 parts © / particularly preferably 200 to

1000 parts category (II)

Component (A) 100 parts Component (B) 5 to 1500 parts, preferably 5 to 500 parts

and particularly preferably 100 to 500 parts of component (C) 50 to 1500 parts, particularly preferably 200 to

Category (III)

Component (A) 100 parts

1000 parts I.

Component (B) 20 to 2000 parts, preferably 50 to 1500 parts

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and particularly preferably 100 to 1500 parts of component (C) 50 to 2000 parts, preferably 200 to 1500 parts

Any one can be used for vulcanizing the above rubber mi vision the usual vulcanization systems can be used. It can be a sulfur vulcanization or a sulfur-free vulcanization been applied. The vulcanization conditions and the like are not particularly limited and they become normal Conditions applied.

A typical example of the rubber compound mentioned above in the case of sulfur vulcanization is the following:

(Component) (parts)

Rubber component 100

Factice 100 to 1500

Plasticizer 200 to 1500

Filler 1 to 200

Antioxidants 0.5 to 6

Sulfur 0.5 to 10

Vulcanization accelerators 1 to 20

Another feature of the rubber sheet according to the invention for one Turntable consists in that no post-treatments are required, as they are generally in the case of a conventional one Rubber plate can be used for a plate roller, for example the application of a halogenation treatment to

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to ensure high surface hearing so that the rubber sheet does not suffer from defects (scratches), and to apply a coating to the surface thereof to prevent the deposition of dust. Although the rubber plate for a turntable of the present invention has a very low hardness as stated above, its impact resilience is high. For this reason, the rubber plate has a characteristic that it is hardly flawed and that dust is hardly deposited thereon. In addition, the rubber sheet has the very useful characteristic that, even if a defect arises or dust adheres to the rubber sheet, the defect disappears and the dust is removed if the rubber sheet is gently swung back and forth like a cloth or wrinkled, because it is very soft * the rubber plate of the invention has the further characteristic feature that is not found in a conventional rubber plate that washing is effective in water and that the rubber plate v cleaned by washing under wrinkling in this Falie can ground / "

The rubber plate for a turntable of the present invention is not particularly limited in configuration, and the conventional configurations can be used. In restricting the configuration of the rubber sheet to those given below, however, one can still a better vibration absorption effect and an improved sound quality can be achieved in combination with the above-mentioned specific physical properties

That is, a preferred configuration of the present invention

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A rubber plate for a turntable is one that has a large number of protrusions on one surface of its disc-shaped plate body is provided.

Since the Gummiρlatte with the above configuration only at the tip of the projections of the same comes into contact with a turntable or a record, is the contact surface extremely small and therefore hardly any external vibrations are transmitted to the record. In addition, the rubber plate for a turntable with the configuration given above a unique effect on:

The substance with the lowest speed of sound is rubber and is the one with the second lowest speed Air. When the surface of the rubber plate with the above specific configuration is in contact with the platter, there is a thin layer of air between the rubber plate and the turntable through the projections, so doß during the Rotation of the turntable the air in this layer through one of the projection-projection-cavities inwards and inwards moved outwards, like when a person breathes. Consequently if the rubber plate and the record on it are in such a situation as if they were resting on air. This will complete isolation from external vibrations and an improvement in sound quality. In a corresponding manner occurs when the surface of the rubber plate with the specific configuration given above is in contact with the record, the specific situation mentioned above between the rubber plate and the record. In this way

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the above configuration shields the vibrations with very deep ones Frequencies, especially not more than 10 Hz, effective and prevents these vibrations from being transmitted to the record. Because of this, howling will occur effectively avoided and there is no risk that the pickup outputs would be modulated with these vibrations.

In the rubber plate with the above-mentioned specific configuration, the shape of the projections is not particularly limited and various shapes can be used of the surface of the head of each projection is as small as measures are possible · such a projection includes a is kammfb'rmig having a shape in which at least the head of the projection to produce a lens-shaped contact with respect to the turntable or the record substantially "the Shapes according to this embodiment can, for example, be roof-shaped and semicircular in section. A projection with a head in the form of a knife edge is particularly preferred. Another desired projection is one with a shape, at least the head of the projection I

is pointed to a substantially point-shaped contact I.

compared to the turntable or the record. ■

The shapes according to this embodiment include a pyramid |

(including a polygonal pyramid, such as a three-I

eckpyiamide, a square pyramid and the like. That also applies to ^;

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the following information), a cone (including an elliptical cone, this also applies to the following information), a dome (including a fast sphere, a hemisphere, a column with a rounded upper section and The like. This also applies to the following information) and the like. A projection with a head as sharp as a needle is particularly preferred. For the projections having two different shapes, it is also sufficient that at least the head thereof is comb-shaped or pointed (pointed), and the shape of the foot thereof is not particularly limited. So can For example, such a projection have a shape in which a head in the form of a roof, in the form of a semicircle, a Pyramid, a cone or a dome or the like., Rests on a foot of a head-free pyramid, a head-free cone or the like * Other shapes can also be used, as long as the contact surface is opposite the turntable or the record is kept as small as possible. For example, head-free pyramid-shaped, paste-shaped or column-shaped Protrusions are used · These protrusions can be provided with indentations on their head in order to ensure a line-shaped contact or a point-shaped contact.

Preferably, the contact area between the protruding surface and the turntable or record makes 0.01 to 10 %, especially 0.01 to 1 %, of the total area of a surface of the rubber sheet (i.e. the area of a circle with the same diameter as the rubber sheet, this also applies to the following information).

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The height of the protrusions is preferably 0.1 to 5 mm, particularly 0.3 to 1.8 mm. When the height is outside the above range, the above-mentioned air breathing behavior occurs difficult to open.

The projections can be arranged regularly or randomly distributed on the body of the rubber plate. A regular one The arrangement can be a concentric circular, spiral, radial arrangement and the like. The individual projections can either be arranged at a suitable distance from one another or be arranged close to one another in contact with one another, or a combination of these arrangements can also be used. If dioso protrusions © are arranged close to each other, For example, the adjacent projections may be integrally connected to each other at their feet (when the projections are closely arranged in the form of concentric circular rows in this manner, this configuration is similar to a configuration in which concentric circular ribs on the floor the Gummiρlatte are provided, each of the ribs with tight adjacent depressions is provided). A preferred arrangement is one in which the projections In the form of concentric circular rows or the like. Are arranged close to each other, so that in a cavity between air is retained by the rows of protrusions between the rubber plate and the platter or record. at In an arrangement according to this embodiment, the trapped air passes through the spaces between the projections which are arranged close to one another, as a result of which better breathing behavior is achieved. As a result, a better vibra-

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tion damping effect and a better sound quality improvement effect occur.

The above-mentioned projections can form an integral unit with the rubber sheet or they can be manufactured separately from the rubber sheet and in a suitable manner, for example by Connect, be attached to it.

Although the rubber sheet having the above specific configuration has protrusion © on one surface, the other surface of the rubber sheet is free from particular restrictions on the configuration other surface, for example, completely flat or with the same projections as indicated above or with concentric circular, spiral or radial grooves or ribs be provided. In addition, indentations or protrusions can be used each with a circular shape, a polygonal shape in the planar plan view regularly (for example concentrically circular, spiral or radial) or in be arranged arbitrarily.

Preferred configurations of the rubber plate for a turntable of the present invention are referred to below explained in more detail on the drawings «

Brief description of the drawings FIGS. 1 and 2 each represent partial plan views

on the respective surfaces of a rubber plate for a plate

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plate according to one embodiment of the present invention;

Fig. 3 is a vertical cross-sectional view taken along the line (V) - (V) of Figures 1 and 2; FIG. 4 is an enlarged cross-sectional view taken along FIG Line (W) - (W) of Figure 1;

Fig. 5 is a vertical cross-sectional view showing an example represents the shape of the edge portion of the rubber plate for a turntable according to the invention (i.e. a vertical Cross-sectional view taken along line (X) - (X) in Fig. 1); Fig. 6 is a partial perspective view of an example for a row (arrangement) of protrusions; 7 and 8 are vertical cross-sectional views representing a Show an example of a protrusion with pre-indentations; Fig. 9 is a partial perspective view of an example for a Reiho (arrangement) in which protrusions with different Shapes are used in combination;

Fig. 10 is a partial vertical cross-sectional view showing shows a situation in which the rubber plate for a turntable according to the invention lies on a turntable and a record lies on the rubber plate; 11 to 13 are respectively top plan views of the rubber platter for a turntable according to the invention on which a plurality of island-shaped rows (arrays) of protrusions are provided;

Figs. 14 and 15 are top plan views of the respective ones Surfaces of a rubber disk for a turntable of the present invention according to another embodiment of the present invention Invention;

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Fig. 16 is a vertical cross-sectional view taken along the line (Y) - (Y) of Figures 14 and 15;

17 and 18 are each flat top views of the respective surfaces of a rubber plate according to the invention according to still a further embodiment of the present invention; 19 is a vertical cross-sectional view along the line (Z) - (Z) of Figs. 17 and 18 and

Figures 20a and 20b, 21a and 21b, 22a and 22b and 23a and 23b are Top views or cross-sectional views of conventional rubber plates for a turntable

In Figs. 1 to 4 (i) stand for the body of a rubber plate and (2) for a central shaft hole. One surface of the body (i) is provided with projections (3) that are close to one another are arranged in contact with one another in concentric circular rows (see FIGS. 1, 3 and 4) (this arrangement of projections is hereinafter referred to as "embodiment A"). Hereinafter, such a concentric circular arrangement of the protrusions © (3), in which the protrusions © (3) are arranged close to each other, is simply called "Roiho (4) of protrusions" designated. The number of rows (4) of protrusions is not particularly limited as long as the body (i) is the Rubber platter is held horizontally on the platter, and it can usually cheat about 3 to about 10 «the ranks (4) of projections can be substantially equidistant from one another along the radial direction of the body (i) of the rubber sheet, or they can, as in FIG and Fig. 3, two or more rows (4) may be arranged close to another row in the form of a block [e.g.

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the two rows (4b) and (4c), (4d) and (4e) and (4f) and (4g) 3, a plurality of such blocks being arranged on the body (1). The rows (4) of projections can be arranged on concentric circular ribs (5) be as shown in Fig. 3 *

• Although in embodiment A the projections (3) in the respective rows (4) are usually flush at their tips, the invention is not limited to this, if, for example, the surface carrying the projections (3) in contact with the record is to be held, there is an embodiment in which the projections (3) in the innermost row (4a) are highest (the row is arranged immediately outside the labeled section of the record) νηά in the order of the rows (4b), ( 4c), (4d), (4e), (4f) and (4g) can possibly be lower, so that the record is held essentially by the innermost part (4a) of the protrusions and in no direct contact with the other rows (4b ), (4c), (4d), (4e), (4f) and (4g) of protrusions, which are different from the row (4a), are * In this embodiment the record is not in contact with the rubber plate at its periphery Contact when the record is stationary.

However, when a cartridge is in the working position for playing the record, the record comes due to the weight of the cartridge in contact with the record, so that the contact area with the rubber plate is small. This further improves the insulation against external vibrations.

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The outermost row (4g) is usually arranged on an edge portion of the body (i) of the rubber sheet. It is preferred that the edge portion of the body (i) be inclined (beveled) outward as illustrated in the vertical cross-sectional view of Fig. 5 (which corresponds to an enlarged cross-sectional view taken along the line (X) - (X) of Fig. 1) , and that the projections of the outermost row (4g) are arranged on this inclined (inclined) edge portion. In this embodiment, the tensile strength (tear resistance) of the rubber disk in the edge portion of the body (i) is decreased because of its small thickness, and the close contact of the rubber disk with the turntable is further improved.

In Embodiment A, the protrusions (3) may have various shapes as described above. The preferred shape is one in which the head of the protrusions (3) is comb-shaped. 4 shows an example of such projections (3) which have a mountain profile with a base that widens downwards Extend towards the body (l) of the rubber sheet, as shown in FIG. In this case, with respect to two adjacent rows [e.g. (4d) and (4e)], the projections (3) in the row (4d) can be aligned with those in the other row (4e) along the radial direction of the body 0) of Overlap the rubber plate. It is desirable, however, the ridges (3a) oaß of the projections (3) in the Reiho (4d) are arranged so that they are located in the valleys (6) between two adjacent projections (3) in the other row (4e) in order to avoid such an overlap, as shown in FIG.

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3CK937S

With this structure, the breathing behavior mentioned above is used in one between the rubber plate and the platter or the Enclosed air layer favors record, whereby a more effective shielding against external vibrations is achieved.

Another preferred shape of the protrusions (3) in the embodiment A is that in which the head of the protrusion (3) is pointed (pointed). A partial perspective view of Fig. 6 [in which the concentric circular row (4) of the projections is again aligned in a straight line] shows a boispiol for such a shape of the projections (3). The protrusions (3) are shown in Fig. 6 as a four-corner pyramid. 4e)] overlap the projections (3) in the row (4d) with those in the other row (4e) along the radial direction of the body (i) of the Gummiρlaite, the pointed heads (3d) of the projection © (3) in the Row (4d) are, however, preferably arranged in the valley (6) between two adjacent projections (3) in the other row (4e) along the radial direction of the body (1) of the rubber sheet so as to avoid overlapping in the same way as in the case of the projections (3) with the chew-shaped heads. Each of the above-mentioned protrusions (3), (3b), but it may also have two or more peaks (3a *) have a single peak, which can be prepared so that the crest of the above-mentioned projection (3) with the comb-shaped head one with Provides recesses, as iij FIGS. 7 and 8 shown. Figure 7 is a

230609/0038

3 (M ° .178

vertical cross-sectional view showing one of the projections (3) with the comb-shaped head along the radial direction of the Body (1) shows the Gutnmiplatte, and Fig. 8 is a vertical cross-sectional view along the circumferential direction *

In the embodiment A, the projections (3) can also the comb-shaped heads and those with the pointed heads can be used in combination or these projections (3) can can be used in combination with projections (3) with other shapes different therefrom in the respective row (4). Ciη An example of such a combination is explained in the form of a 6xner perspective view in FIG however, a perspective view with the concentric circular row (4) of protrusions again aligned in a straight line]. In Fig. 9, the projections are (3) with the pointed heads and the projections (3) with the comb-shaped heads [the latter differ from those in Fig. but in that the ridges (3a) are aligned along the circumferential direction of the body (l) of the rubber plate] alternately aligned with each other.

As explained in FIGS. 2 and 3, it is desirable that the opposite surfaces of those provided with the projections (3) Rubber sheet according to embodiment A is provided with concentric circular grooves (7) in a position corresponding to the respective rows (4) of the protrusions, so that the rubber sheet as a whole has a substantially uniform thickness. In this case, each of the grooves (7) corresponding to one of the individual rows (4) of the projections or corresponding to one

230609/0038

ιέ

A plurality of adjacent rows (4) of the projections may be shaped as shown in Fig. 3 [for example, one of the grooves (7) is provided for each of the ribs (5)]. A rubber sheet having such a structure is lighter in weight, and a layer of air is trapped in the grooves (7), thereby improving vibration absorption and sound quality. In the case of the rubber plate with the rows (4) of protrusions on one surface and the grooves (7) on the opposite surface, the sound quality of the reproduced sounds (tones) clearly differs depending on which surface of the rubber plate with the turntable (or the record) should be brought into contact. An advantage is therefore obtained in that the appropriate selection of the surface of the rubber plate to be brought into contact with the turntable (or the record) leads to the achievement of pleasantly reproduced sounds (tones).

The platter is usually in its middle section provided with openings between the central shaft and its edge. It is therefore advantageous that when the grooves (7) provided surface is to be brought into contact with the turntable, the innermost groove (7) removed from the openings is held and a layer of air is trapped between at least the inner groove (7) and the turntable.

If the surface provided with the rows (4) of protrusions is in contact with the record and the other surface provided with the grooves (7) is in contact with the turntable according to the present invention, the preferred one is

230609/0038

The configuration of the rubber sheets in which the protrusions (3) are highest in the innermost row (4a) and in the order of rows (4b), (4c), (4d), (4e), (4f) and (4g gradually) and remove oaß at least the innermost groove (7) is kept away from the openings of the turntable. The figure shows a situation in which a rubber platter with such a configuration is placed on a turntable and the record rests on the rubber platter. the number (lO) the openings of the turntable and the number (il) the record. In the situation shown in Fig. 10, the rubber plate is in close contact in its middle section (corresponding to the labeled area of the record) with the turntable (8), above the middle section of the guromiplate, which is in close contact with the turntable, a layer of air (12) is enclosed between the record (left) and the innermost row (4a) of the projections on the rubber plate. The air in the layer (12) flows inward and outward through the spaces between the adjacent protrusions in the row (4a), thereby causing breathing during playback of the record, as indicated above. On the other hand, the innermost groove (7a) of the rubber plate is kept away from the openings (10) of the turntable (8) so that a layer of air is hermetically enclosed within the groove (7a). This combination of the middle section of the rubber plate, which is in close contact with the turntable, the air layer (12), which causes breathing, and the layer of the air hermetically enclosed in the groove (7) results in a particularly good vibration damping effect and a Volume-

230609/0038

3041378

SO

quality improvement effect.

Although a configuration of the GuromipJatte has been explained above in which the air between the rubber disk and the record or turntable is trapped by the concentric circular rows (4) of closely spaced protrusions, the arrangement of the protrusions is to trap air , not limited to that. For example, as shown in plan view in Figures 11-13, there are arrangements in which a plurality of circular (including elliptical) rows of closely spaced projections (3), a plurality of polygonal (including a triangular , square and the like) rows of projections (3) arranged close to one another, a multiplicity of fan-shaped rows of projections (3) arranged close to one another and the like (these are hereinafter referred to as `` insular rows (13) of projections _{n ''} In this embodiment, air is trapped between the individual insular rows (13) of protrusions, whereby breathing is achieved. The insular rows (13) of protrusions need not have the same dimension and for example, smaller insular rows (13) can be arranged between larger insular rows (13), wi e shown in FIG. 11. In addition, insular rows (13) of protrusions with mutually different shapes can be used in common, as shown in FIG. 13. In this embodiment, the concentric circular row (4) of protrusions in the central portion or in the

230609/0038

30-A.937S

middle portion or in the peripheral portion of the body (l) the rubber plate be arranged, as in Figs. Π and 12 shown.

Fig. 14 shows a plan view of a surface of the rubber plate for a turntable according to another embodiment of the present invention, and Fig. 15 shows one plan view of the other surface of the rubber sheet and FIG. 16 shows a vertical cross-sectional view along it Line (Υ) - (Υ) in Figs. 14 and 15. In one surface the body (i) of the rubber plate are provided with projections (3), which are arranged close to one another in the form of a spiral row (see. Fig. 14) (this arrangement of projections hereinafter referred to as "Embodiment B"). Below such a spiral row of closely spaced projections (3) is simply referred to as "row (14) of projections".

In Embodiment B, the respective protrusions (3) in row (14) may be flush at their tips, or they may gradually decrease toward the periphery of the rubber sheet for the same reason as in Embodiment A. Each protrusion (3) may also have the various shapes described above, but a protrusion with a comb-shaped head or a pointed head is preferred, as in embodiment A. In the case of the protrusions with a comb-shaped head, it is preferred that the ridges are substantially along the radial direction dos body (1) of the rubber sheet are aligned, as shown in FIG _o fourteenth The protrusions with the comb

230609/0038

_-β ΐ. 3043878

$ 1

shaped head can be equipped with indentations for Achievement of two or more peaks, as shown in FIGS. 7 and 8. In addition, in the series (14) of Projections the projections with the comb-shaped head and the Projections with the pointed head can be used in combination with each other and these projections can also be used in combination can be used with protrusions of other shapes as shown in FIG. In the embodiment B is the edge portion of the body (1) of the rubber plate preferably inclined outwards (beveled) similar to the embodiment A.

With respect to the other surface of the rubber plate gemdß with VorsprUngen (3) of embodiment B is equipped, it is desirable AASS a portion thereof corresponding to the row (14) of projections is made concave, as shown in FIGS. And 16 shown [as a result one obtains a spiral convex rib (15) in the "remaining part] to thereby make the thickness of the rubber sheet as Qanze substantially uniformly TM. The edge portion of the other surface is usually provided with a flange portion (16) to trap air.

Figure 17 is a top plan view of one surface of the rubber sheet for a turntable according to another embodiment of the invention, FIG. 18 shows a plane A plan view of the other surface of the rubber sheet and FIG. 19 shows a vertical cross-sectional view along FIG Line (Z) - (Z) of Figures 17 and 18. On the other surface

230C09 / 0038

304 ° "7S

of the body (1) of the rubber plate, projections (3) are provided, which are arranged close to one another in the form of radial rows (see. Fig. 17) (this arrangement of the projections is hereinafter referred to as "embodiment C"). In the following, the radial rows of projections arranged close to one another will be referred to simply as "row (17) of projections ¹¹ ".

In embodiment C, the respective projections (3) in the rows (17) all be flush at their tips or gradually lower towards the circumference of the rubber sheet for the same reason as Embodiment A. Each protrusion (3) may take the various shapes described above have a protrusion (3) with a commförinigen head or a However, a pointed head is preferred as in the embodiment A. The projections with the comb-shaped head can be provided with depressions to form two or more points, as shown in Figs. 7 and 8 * In the row (17) of projection gon For example, the protrusions with the comb-shaped head and the protrusions with the pointed head can be used in combination with each other, and also these protrusions can be used in combination with protrusions of other shapes, as shown in FIG. In the embodiment C, the edge portion of the body (l) of the rubber plate is preferably inclined outwards (obliquely), as in embodiment A.

As for the other surface of the rubber sheet provided with the projections (3) according to Embodiment C, it is It is also desirable that parts thereof corresponding to the rows (17) of the protrusions ^ are made radially concave for

230609/0038

3049873

Creation of radially concave parts (18) to the thickness of the To make rubber sheet as a whole essentially uniform, as shown in Figs. 18 and 19 «

In the embodiments A to C, the protrusions (3) are tight arranged side by side, but the arrangement of the projections (3) is not necessarily limited to this. You can also be spaced at any suitable distance from one another.

The rubber plate according to the invention for a turntable is subject no particular restrictions on their thickness. The rubber sheet usually has a maximum thickness in the Of the order of 2 to 8 mm, a minimum thickness of the order of 0.1 to 3 mm and an average thickness in of the order of 0.1 to 6 mm, in particular from 0.5 to 2 mm *

The rubber sheet according to the invention can be manufactured in a conventional manner. For example, the rubber compound given above can be vulcanized directly in the press into a shape with a given configuration. Alternatively, a non-vulcanized mixture in the form of a plate is produced by calender molding or extrusion molding and then subjected to vulcanization in the press. Injection molding is also possible. It is desirable that the projections (3) are formed in the mold at the same time, but they can also be formed by cutting out after vulcanization. Further, the projections (3) can be made independently of the body (1) of the rubber sheet dom body 0) of the rubber plate under

230 ü ü9 / 0030

30Λ9373

Turning of a suitable adhesive or the like will·

Best mode of carrying out the invention

The rubber plate according to the invention for a turntable is explained below with reference to examples and comparative examples.

230 6 09/0038

Examples 1 to 4

Using the rubber smell given in Table 1 rubber plates were made for a turntable.

Table 1 Share) 2 3 1 2 4th 1 Wax mark Gunimi mixture (in 250 250 2 12th 250 2 20th 260 120 2 1 Examples 200 690 280 9 Norsorex 150 NA
(Footnote 1) 250 10 - - White Tactice S.
(Footnote 2) 225 50 25th 50 Sunthene 255
(Footnote 3) 410 5 5 VJl Dioctyl phthalate 45 1 FEP carbon off 50 2 zinc oxide 5 2 Stearic acid 1 8th Sumilizer MDP
(Footnote 4) 2 jraKenes sulfur 2.5 Sunceller CZ
(Footnote 5) 10 Footnotes 1: Pol ynorbornen (smells

Norsorex, average molecular weight not less than 2 χ 10) diluted (stretched) with 150 parts of naphthenic oil to 100 parts of polynorbornene, sold by Nip Pon Zeon Co., Ltd.

2: White factis manufactured by Temma Sabu Kako Kabushiki Eaisha

3ϊ naphthenic oil manufactured by Japan company Sunoil Co., Ltd.

4: 2.2 ^l -Methylene bis (4 ~ methyl-6-tert-butylphenol)

230809/0038

manufactured by Sumitomo Chemical Co., Ltd.

Footnote 5? N-Cyclohexyl ^ -benzothiazole sulfenamide from Sanshin Kagaku Kabushiki Kaisha.

The rubber component was first cleaned at about 60 ⁰ C, using a Banbury mixer and a mixing roll with other components kneaded and rolled into a about 2 to about 3 mm thick plate. A disk was cut out of the plate and placed under a die using a press device of a given shape

Pressure of 150 kg / cm and vulcanized for t minutes.

Pressure of 150 kg / cm and at a temperature of 155 ⁰ C 20

In this way, those shown in FIGS. 1 to 4 and 10 were obtained Rubber plates for a platter with a diameter of 292 mm, a maximum thickness of 3.7 mm, a minimum Thickness of 1.9 nra, a height of the protrusions (3) in the innermost row (4-a) of 0.5 ffln j ^ height (EL) in Fig. 3Ί or 1.5 mm 1/2 height (Hp) in Fig. 3/1 “a length of the combs of the projections (3) from about 3 to about 6.5 mm, a distance between adjacent projections (3) from about 5 to about 6 mm, a depth of the grooves (7) of 1 mm and a width of the grooves (7) (in the radial direction) of about 30 mm (the individual Projections (3) became progressively lower towards the circumference of the rubber plate).

The rubber plates obtained were different physical properties measured. The results are given in Table 2 below. The measurements of the impact elasticity, the tensile strength and elongation shown in Table II were determined in accordance with JIS K 6301-1969 carried out,

230609/0038

- ar 30493, Examples 4th ts 3 9 Table 2 7th 74 72 10 1 2 19th 281 4 5 367 68 60 8 21 398 575

Physical constants

Α hardness (°) impact elasticity (S) tensile strength (kg / cm) elongation $) specific weight 0.977 0.982 1.003 0.987

The total area of the ridges of the projections (3) (total number 852) in j or rubber sheet of Examples 1 to 4 made up about 1.45 % of the total area of the one surface of the rubber plate (assuming that the width of the ridges 0 , 25 mm). When a glass plate with the same dimensions as the rubber plate and a thickness of 2 mm (weight about 300 g) was placed on one surface of the rubber plate having the projections (3), the glass plate was essentially only at the crests of the projections (3 ) in the innermost strainer (4a) in contact with the rubber plate. In this case, the ratio between the contact area and the total area of the one surface of the rubber sheet was about 0.1 %. The preferred configuration of the rubber plate for a turntable according to the present invention is characterized in that the contact area is so small.

In addition, the tests described below were carried out on the rubber sheets of Examples 1 to 4. For comparison the same tests were also carried out with four types of rubber plates that are commercially available on the Turntables available on the market were attached. The rubber sheets used here are in the table below 3 summarized.

230 0 09/0038

■ <- - ' —irr

$ 9

30A

Comparative example θ material

Table 3

Butyl SBR / NK
rubber

A hardness (°)
Impact resilience (#) Specific weight, halogenation configuration (footnote 3)

note 1) rubber

Styrene / butyl butadiene rubber

50

57 33

19th

1.223 1.356

τιc ** i τη * ί Q τη

XIC? XXl <Jc * «J ^ -

Fig.20a Fig.21a Fig.22a

Pig.20b Pig.21b Fig.22b

(Footnote 2) 36

1.642

Fig.23a Fig.23b

Footnote 1

Mixture of styrene-butadiene rubber and natural rubber

The butylgunimi body is covered with a mixture of natural rubber and styrene-butadiene rubber. 20a and 20b, 21a and 21b, 22a and 22b and 23a and 23b are plan views and cross-sectional views, respectively, of the guru plates according to Comparative Examples 1 to 4. In these drawings, the thicknesses (h ,,), (fcO, (h, ), (h ^), ^ h ₁ -), (hg), (h ") and (hg) the rubber sheets have the following values:

(b ^): 4.2 mm

(hp) ϊ 3.5 BHH

3.5

2.5

(h ₈ ):

mm mm mm mm mm mm

The summaries of the configurations were as follows;

Comparative example 1

Upper surface: In its center there is a circular

23Q6Ü9 / 0038

3049378

deep ting to a depth of 0.7 ^ram provided Lower surface: Flat

Comparative example 2

Upper surface: at its center is a circular one Depth of 1.0 mm recess is provided and it is a concentric circular groove of depth of 1.0 mm provided

Lower surface: even

Comparative example 3

Upper surface: at its center is a circular one

Depth of 1.0 mm intended. Lower surface: Flat

Comparative example A-

Upper surface: there are three concentric circular ones

Billen a depth of 0.5 mm-provided Lower surface: even

It should be noted that the lower surfaces of the rubber disks according to Comparative Examples 1 to H- are all flat and that the flat surfaces should be in contact with the turntable. In the tests described below, the rubber plates of Comparative Examples 1 to 4 were therefore mounted so that their flat lower surface was in contact with the turntable.

(1) Sound quality test

(i) Playback device pre-main amplifier: AU-D90? (made by the

Sansui Electric Co., Ltd.) Turntable: DP-40F (manufactured by Pirma

Nippon Columbia Co., Ltd.)

Pickup: V-15 »Type 3 (manufactured by the company Shure Brothers, Inc.)

230609/0038

304 ^ 73

Loudspeaker: DS-401 (manufactured by Mitsubishi Electric Corporation)

(ii) Listing

about 40 tatami mat room (equipped with air conditioning and a fan)

Floor: vinyl tiled (with a layer of mortar underneath) Ceiling: Smooth, non-flammable material (no sound absorption opening)
Interior walls: plywood (wood veneer)

(iii) Test Procedure

A panel of four experienced listeners A, B, C and D was commissioned to listen to the records listed below and to evaluate them on the basis of the following parameters placed on the turntable so that the surface shown in FIG. 1 is provided with the projections (3) Surface! was in contact with the record »

Female vowel piece

Record title: Waltzes, Chansons and Tangos

(Nippon Phonogram Co ·, Ltd ·) Singer :. Ginamaria Hidalgo Accompaniment: Hugo Videla (guitar) and others Program: Te Pido Quo Lo Pienses Parameters:

(a) Whether the reproduced sounds (tones) are human Sounds (tones) came close,

(b) whether the soprano high frequency range was not distorted,

230609/0038

3049373

(c) whether the accompanying guitar sounds (tones) are not were stronger than the vowel sounds (tones)

(d) whether the presence impressions were rich

(ß) concert piece

Record title: "Le Quattro Stagioni", No. 8 by Vivaldi (Nippon Phonogram Co ₀ , Ltd «)

Executives: Roberto Michelucci (violin) and I Musici Program: Concert No. 1, E major RV 269 "Spring" (spring)

Parameter:

(a) whether the chords are lively,

(b) whether the cooking tone area is not distorted,

(c) whether the ßaß area is reproduced well,

(d) whether the presence impressions are rich "

Flamenco guitar

Record title: Manolo Sanlucar in Japan (RVC Corporation)

Performers: Manolo Sanlucar (guitar), Isidro (guitar) and Jose Miguel (piano)
Program: Callej & n del Carmen
Parameter:

(a) whether the battery sounds are reproduced well,

(b) whether the high frequency range is not distorted,

(c) whether the AnochlUgo of a guitar well wiodorgogobon will,

(d) whether the presence impressions are rich ”.

The ratings with respect to the above parameters have been

determined using the following 5-point system:

5 points: exceptionally good

4 points: pretty good

230 6 09/0038

Η 3 O A

3 points: good 2 points: usual 1 point ι ' bad

The sum of the points for each of the parameters given by each of the listeners multiplied by 5 was taken as the overall rating each of the listeners viewed (if all parameters are rated with 5 points, the total rating would be a maximum of (100 points)) » The average of the overall ratings of the 4th Listener calculated "

The results are given in Tables 4 to 9 below *

230609/0038

parameter

example 1

Table 4
(Female vowel piece)

Example 2 Example 3 Example 4

Proximity to human voices

55

Treble distortion 5 5 5 5 5 5

Accompanying
guitar

Presence indijuck

5 5 5 5 5 5 5 5 5 5

53 5 55 5

5555555 5

5535353 5

5553535 5

5355535 5

Overall rating 100 100 100 100 100 100 9 0 100 100 9 0 9 0 9 0 9 0 8 0 9 0 100

Average value 100 98 92 90

N) CO O CT C. CD

O O CO

Parcmeter

Comparative example 1

Proximity to Raenschli voices

Treble distortion

Accompanying guitar

Presence imprint

2 δ

δ 5

δ δ

Table δ (female vowel piece)

Comparative example 2

Comparative example 3

Comparative example 4

δ δ

2 δ

1 1

Overall valuation ₄₅ 70 7 0 55 δΟ 40 40 40 20 35 55 55 25 40 40 40

average value

60

Table 6
(Concert piece)

parameter A. example 1 D. example A. B. 9 2 5 D. example B. 9 3 C. 0 D. A. Example 4 C. 88 - D. ι
^ ι 5 B. C. 5 5 5 C. 5 A. 5 5 δ 5 B. 5 5 co
O chord
sounds 5 5 5 5 δ 5 5 5 δ 5 5 5 δ δ δ δ 609 / tweeter
strain cn cn 5 5 cn cn in in in in δ 5
5 5 δ
5 δ
5 cn cn 5
δ 5 5
5 cn cn U)
O 0038 BcB
Presence
pressure
Ge saint rating 100 5
5 cn cn 100 90 100 cn cn 100 cn cn 90 90 90 80 cn cn 90 90 'X)
OO Average
value 100 1 00 90 90 90 100

Table 7 (concert piece)

parameter

Comparative example 1

Comparative example 2

Comparative example 3

Comparative example 4

2308t Chord-
sounds 3 3 5 69 3 3 2 A. 5 7th 5 2 2 2 45 2 3 2 45 3 3 CO
O 39/0038 High frequency distortion
tion 5
2 5
3 5
3 5
3 2
2 , 2
5 K) K) 2
3 2
2 3
3 N) Ol 2
2 2 • 2
3 1
5 2
2 CD
CO Presence 3 5 3 3 2 1 2 2 2 3 2 2 3 2 1 2 pressure
Overall rating 80 60 7 0 45 40 55 50 40 55 45 40 50 40 45 tion
Average value

Parameters - A. example 1 C. D. Tabel 8th B. 2 C. D. Example 3 B. C. D. A. example 4th
C. D. Chord sounds 5 B. 5 5 δ 5 5 A. 5 δ δ 5 B. 5 δ Tweeter B. 5 δ 5 (Flamenco guitar) 5 5 5 5 5 5 5 5 δ 5 5 strain 5 example 5 5 ro
co Guitar on
blows
Presence imprint 5
5 cn cn in in A. δ
5 cn cn in to δ
5 5
δ cn cn LOO 5
δ 5
5 O
C5 cn cn 5 δ
5 δ
5 O
CD 5 / 0038 5
5

Overall assessment 100 100 100 100 100 80 100 100 90 90 80 90 90 80 90 90 tion

average value

100

95

Tobelle 9 (Flaraenco guitar)

parameter

ο chord sounds

<£> tweeter

Q strain

^ω guitar
°° hit

Comparative example 1

Comparative example 2

Comparative example 3

THERE

THERE

Comparative,. example 4

B C

δ 5

δ 5

2 δ presence impression ^{3 2}

δ

δ δ δ

1 δ

2 2

δ
2

2
2

δ 2

2 2

2 2

Overall assessment 6 5 6 5.

average value

66

2

δ δ

2

2

60 75 45 45 55 40 40 50 55 45 40 40 45 δ5

.'J CO

(2) Howl test

Similar to the sound quality test, listeners A, B, C and D were assigned the three types of records mentioned above and determine the occurrence or absence of howling based on the definition below. It became a pre-main ~ Amplifier used, in which the high frequency range and the bass on ',' low 'were set while the volume was set to Π o'clock showed «

Definition of howling: Howling is understood to mean that the sound quality of reproduced sounds is impaired by external vibrations and the reproduction of the original sounds (e.g. is influenced in a disadvantageous way by human voices as such in the case of a vowel piece

The howl was rated under. Application of a 10-point system ", The rating "10 points" indicates that no howl was observed and the original sounds were reproduced as they were · A decrease in the score indicates an increase in howling and the rating "Ί point" indicates that the howling was very strong and that absolutely pure normally reproduced sounds were obtained The results are given in Table 10 below, in which those used with respect to the rubber sheets of Examples 1-4 The terms "front" and "back" have the following meanings to have;

Front: The surface as shown in Fig. I. J_d «h · the surface provided with the projections (3) thereon! is considered to be the upper surface (d H. than the surface that is in contact with the record) ο

230609/0038

-400 -

Backside ι the surface as shown in Fig. 2 r_d «h> the surface provided with the grooves (7)! is considered the upper surface

The score given in Table IO gives the average value the points given by the four listeners again (fractions were rounded down)

230609/0038

Table 10

Example ·! Ex, 2 Beisp.3 Beisp.4 _See ^ See · _{See> See #}

vinyl record 0 R. 0 R. 0 R. 0 R. Example 1 Example «2 Example 3 Bexsp « cn ο Feminine Vo 1 0 1 0 9 10 9 9 9 9 5 4th 4th 4th CD Kalstück χ O Concert piece 9 0 8th 9 8th 8th 8th 9 4th 4th O O Flamenco guitar 9 9 8th 8th 8th 8th 8th 8th 4th 4th 3 4th CO

0: front
Ri back

In the above-described sound quality test and in the above-described howling test, the rubber sheets of the present invention (Examples 1 to A) gave exceptionally good results compared with the conventional rubber sheets (Comparative Examples 1 to 4). ie the specific configuration of the rubber sheet according to the invention contributed to these results, ie the rubber sheet according to the invention is characterized by an extremely low hardness, ie by a hardness of not more than 30, preferably not more than 20, in the Α hardness up to not less than 15, preferably not less than 30 ι in the F hardness and a high elasticity, ie an impact elasticity of not less than 40 %, preferably of not less than 50 %. The rubber sheet according to the invention has the specific property that they are in close contact with the record or the turntable and prevents slippage or resonance, as can be seen from the results of the slip tests and lift tests discussed below, and also ensures a reduction in the contact area and good breathing behavior when using the specific configuration with the protrusions «. As a result of the combination of these excellent properties, the rubber sheet effectively prevents the sound quality of reproduced sounds from being deteriorated by howling or external vibration, and allows the original sounds to be reproduced as realistically as they are 1 has a low hardness, ie of 24 in the Α hardness, but a low impact resilience, ie of 19 %, and the rubber sheets of Comparative Examples 2 to 4 have a high hardness. All conventional rubber sheets therefore meet

2 Ί U b ü 9/0 0 3 0

neither the hardness and impact elasticity requirements as set out in the present invention are defined, nor prevent them from being sufficient Measures the deterioration (deterioration) in the sound quality of reproduced sounds caused by howling or external vibrations

(3) slip test

After the rubber sheet has been put on the Turntable of a turntable (PL-380, manufactured by the Company Pioneer Electronic Corporation) and was rotated at a speed of 33 1/3 rpm at the same time Placing a stylus on the record, the record was stopped by lightly touching the two opposite ones radial ends of the record with both hands so that the operator can observe the stopping movement of the turntable could »The rubber platter was considered" suitable "if the platter when pausing, the rotation of the record immediately or within stopped after a second, and it was rated "unsuitable" ~ see if after stopping the rotation of the 'vinyl record it It took more than two seconds for the turntable to stop too. The results obtained are shown in Table 11 below specified »

Table 11 valuation Rubber sheet suitable
Il _. ... front
Example 1 _Dll . ..
₍ KUcrcpage π
H _D. . , ο front
Example 2 _D ", ..
^r back

For example ^Ίο £ * £ & * ° 2 30609/0038

3040 ^ 78

_D. . - . Front. .

Bexspxel 4 _{back side} geexgnet

See example 1 unsuitable See example 2 "

See example 3 ⁿ

See example 4 ⁿ

In the above test, all rubber sheets of Examples 1 to 4 were suitable, while even the rubber sheet of Comparative Example 1 (which had not been subjected to halogenation treatment), the apparently had the highest frictional resistance among the rubber sheets of Comparative Examples 1 to 4, was unsuitable.

(4) lift test

This test was carried out to determine the contactor properties of the To evaluate rubber sheets "

The rubber sheet L to ^be lifted The rubber sheet of Comparative Example 2 (weight 340 g) was used, after its central shaft opening was closed with a cellophane tape, was placed on a desk (desk) and the rubber sheet to be tested was placed thereon so that the central shaft holes matched. »Then the panels were slid as a unity on the surface of the desk (desk) over the edge of the desk (desk) until it was floating freely in the air, with the test rubber panel with doumen and forefinger in its central shaft opening was grasped to plug the opening to determine whether the rubber sheet to be lifted would fall or not. Since 'the upper surface of the rubber sheet to be lifted

230609/0038

Comparative Example 3 had already been subjected to halogenation treatment, the above test was carried out to examine the influence of the halogenation treatment in the case where the test Guraroi plate adhered to the upper surface of the rubber sheet of Comparative Example 3 to be lifted, and also fu _In the event that the test rubber sheet adhered to the untreated lower surface of the rubber sheets of Comparative Example 3. The rubber sheet of Example 1 and the rubber sheet of Comparative Example 1 (which were believed to have the best contacting properties among Comparative Examples 1 to 4) were used as rubber sheets to be tested In the case of the rubber sheet of Example 1, the surface was kept in contact with the rubber sheet to be lifted as shown in FIG. rait the Guraiai plate to be lifted kept in contact no

The result was that the gumrai plate of Comparative Example 1 had the rubber sheet to be lifted absolutely did not tighten and fell off while the rubber sheet of Example 1 tightened the rubber sheet to be lifted like a suction cup and lifted it up so that the gumra sheet Couldn't fall down

The above test shows that with the rubber sheet of Example 1, the Rubber sheet of Comparative Example 3 with a weight of 340 g could be lifted. It was then determined what weight in Gram could lift the rubber sheet of Example 1

A plurality of the rubber sheets of Comparative Example 3 were piled up and connected to each other using a cellophane strip. Then the rubber sheet of Example 1 was then

230 ü09 / 0038

"7 ~

and the qfttest was carried out in the same way as the above Test completed"

As a result, the rubber sheet of Example 1 was found to have one Stack of 10 rubber sheets of Comparative Example 3 (weight 3.4 kg) was able to lift · When trying to lift the stack of 10 rubber sheets of Comparative Example 3 occurred on the part of the rubber plate of Example 1 had a break where it was caught by the operator and therefore the test could no longer be carried out.

From the above results of the slip and lift tests goes shows that the rubber sheet according to the invention has a high frictional resistance and has excellent contact properties and also acts as a stabilizer when using the invention Rubber sheet is therefore not required for such a stabilizer

(5) scratch test

This test was carried out with the rubber sheet of Example 1 and the rubber sheet of Comparative Example 3 (which was subjected to halogenation treatment).

A turntable cartridge (SF-135, manufactured by Matsushita Electric Industrial Co., Ltd.) was provided with a weight and covered with a Kraft paper so that a weight of about 30 g on the gumra plate on the platter o a contact area of about 2 era weighed down · The pickup with the Weight was placed about 5 cm within the circumference of the rubber sheet and the, turntable was at a speed of

230609/0 038

Rotated 45 rpm «The platter was braked to a stop every minute to see if there were any scratch marks»

As a result, it was found that in the case of the rubber sheet of the example 1 faint markings appeared after 30 minutes, but that when rubbed once with a finger, these marks disappeared again without leaving a trace · On the other hand, stepped in the case of the rubber sheet of Comparative Example 3, an unlimited number of fine scratch marks, although not very noticeable v / aren, appeared after 3 minutes, and these markings could not be removed again by rubbing with a finger «In addition, strong rubbing marks and marks appeared after 30 minutes these marks could not be removed again by rubbing with a finger

The conventional rubber sheets mostly undergo halogenation treatment subjected to increase its surface hardness in order to prevent the surface from being damaged as in the case of the rubber sheet of the Comparative Example 3 is damaged As is apparent from the above results, the rubber sheet of the present invention, although Yes has not been subjected to halogenation treatment, is less damaged than the conventional ones subjected to the halogenation treatment In addition, in the case of the rubber sheet according to the invention, scratch marks, if they are slight, can be can be easily removed by rubbing with a finger »

(6) Staubhaftunys roars

The ashes on the burning tip of a cigarette 10 ram in length

230609/0038

-M-

was dropped on a piece of paper, rubbed with a finger and placed on the test rubber sheet 2 cm away from its center. The rubber sheet was held up with both ends and then one of the hands was removed so that the rubber plate hung down. Using the index finger, the plate was with constant pressure tapped three times from the back of the plate in the part where the ashes fell «

As a result, it was found that the ashes in the case of the rubber sheets of Examples 1 to 4 could be removed almost completely However, ashes in the form of a fan with the original position the ash adhering to its tip "The amount of the ash retained was particularly large in the case of the non-halogenated rubber sheet of Comparative Example 1"

From the above results, it can be seen that dust on the invention Rubber sheet adheres less than to conventional rubber sheets (comparative examples 2 to 4) which have been subjected to halogenation treatment have been subjected to reduce the possibility of dust adhesion,

Examples 5 “to JSt

In the same way as in Examples 1 to 4, rubber sheets were made made for a turntable, but this time the rubber compounds were changed as indicated in table 12 »

The physical cons tanton of the Orhalionon rubber plates were thereby measured in the same way as in Examples 1 to 4 «The results are also given in Table 12 *

230609/0038

3040V7S

• Table 12

Examples 5 6th 5 1 7th 8th ß Rubber composition (in parts) 1 54 Norsorex (as described above) ßP 75 ?, 5 ßP IPP ß Nipol SBR 1712 (footnote l) 2P Tf 1P I " 402 Esplene 505 (footnote 2) a ? 5 B » r ? 1 / P15 Nipol IR 2200 (footnote ß) ff tr 7th 2P .- White Factice S. 420 £ 30 $ 5 320 210 Sunthene 255 56p 4.50 5 440 ß20 Sunpar HO (footnote 4) sr gr 155 ? P Sundex 790 (footnote 5) r- .- P, 979 40 Dioctyl phthalate ßP r * 50 FEF carbon 40 ßo 40 HAF carbon 4P MT ~ carbon ε « a 2P zinc oxide 5 5 5 Stearic acid 1 1 Sumilizer MDP 1 1 sulfur £, 5 2/5 2.5 Sunceller CZ ? 0 10 9 Physical constants Α hardness (°) 'Oil ö Impact elasticity (%) Φ7 59 Tensile strength (kg / cm) 2 9 Elongation {%) 257 Specific weight Q _f 945 P, 95i

Footnote Ij Styrpl-ButadieprGummi | manufactured by the company Nippon Zeon Qof _f Ltd.

230609/0038

3040073

Footnote 2ί Ethylene Propylene Diene Rubber Manufactured by the Company

Sumitomo Chemical Co., Ltd "
Footnote 3: Isoprene rubber manufactured by Nippon Zeon Co.,

Ltd.
Footnote 4: Paraffin oil, manufactured by Japan Sunoil Co *,

Ltd.
Footnote 5: Aromatic oil manufactured by Japan Sunoil Company

Co., Ltd.

The rubber sheets obtained in Examples 5 to 8 also allowed the reproduction of sounds in an excellent tone quality like the rubber sheets obtained in Examples 1 to 4.

Examples 9-10

Rubber disks for a turntable were produced in the same manner as in Examples 1 to 4 except this time the rubber fittings as indicated in the following Table 13, changed The physical constants of the rubber sheets thus obtained were determined in the same manner as in Examples 1 measured to 4. The results are also given in Table 13.

Table 13

Examples 9 10 Rubber composition (in parts) Norsorex 150 NA 250 250 DOG Factice F 10 (footnote l) 240 300 Sunthene 255 130 120 Dioctyl phthalate < 10

230609/0038

SRF carbon 40

MT carbon

Zinc Oxide Stearic Acid Antioxidant DOA (Footnote 2) Suntight S (Footnote 3) Sulfur Sunceller CZ

Physical constants Α hardness (°) impact elasticity {%) tensile strength (kg / cm)

M. 1 1 35 5 2 5 1 8th 1 1 Ί 2 6th

strain
specific weight

18th 23 71 73 21st 16 283 293 0.997 0.999

Footnote II Amber Sulfur Factice, Manufactured By of the company DOG Deutsche Olfabrik Ges. f "Chem · Erz"

mbH & Co
Footnote 2% Diphenylamine Antioxidant Manufactured by the

Bayer AG company
Footnote 3: Microcrystalline wax manufactured by Seiko Kagaku Kabushiki Kaisha

When a glass plate weighing about 300 g was placed on the respective rubber sheets of Examples 9 to 10, the contact area accounted for about 0.01 % of the total area of a surface of the rubber sheet.

23UG09 / 0038

* f- 3049378

ν S

The following tests were carried out with the rubber sheets of Examples 9 and 10.

(1) Sound quality test

This test was carried out in the same manner as in Examples 1 to 4, but this time the test plate and the parameters were changed as follows: The results are in Tables 14 and 15 together with those with the rubber sheets of Examples 4 and of Comparative Examples 1 to 4 are given

Test plate

Record title: Bach: Toccata und Fuge, Ε «Power Biggs in the Thomas Church (CBS Sony Inc.) Performers: E, Power Biggs (organ)
Program: Toccata and Fugue in D minor

Parameter:

(a) whether special sounds of an organ pipe are played,

(b) whether the high notes are clear,

(c) whether the bass is solemn,

(d) whether the melody is neatly separated from the accompaniment

230009/0038

Table U

parameter

ο Sounds of a pipe organ

<ß High notes

ο Bo3

Melody and accompaniment

Overall rating

Average rating

example B. 9 C. D. A. Example 10 C. 98 D. A. example 90 4th D. A. 5 5 5 5 B. 4th 5 4th B. C. 4th 5 5 5 5 5 5 4th 5 5 4th δ 5 5 5 5 5 5 5 5 5 4th 4th 5 5 5 5 5 5 5 5 5 5 5 5 4th 5 . 5 100 100 100 100 5 90 100 90 5 5 95 100 1 0 100 90 85 0

CO O

CO CO

CD

Tabel

High notes
Bass

Melody and accompaniment

Overall rating

See Example 1 See Example 2 See Example 3

See example 4

ο parameter ^

^ Sounds one

• ^ pipe organ 2

2 2

Average rating-

δ 2

δ δ

2 δ 2

2 2 2

1
2
2

2 2

1
2

1 1 2

2 2

2 1

δ 1

1 1

40 45 50 50 50 40 35 30 30 25 30 35 25 25 40 25

46

34 30th

29

- <«- 3043878

(2) Howl test

The test was carried out in the same manner as in Examples 1 to 4, but this time the test plate was replaced with the one used in the above sound quality test, and the test was carried out only in the case where the rubber plate was internally with the surface shown in Fig. 1, the surface J provided with the projections (3) was in contact with the plate. The results are shown in Table 16 together with φψη results obtained with the rubber sheets of Example 4 and Comparative Examples 1 to 4.

Table 16
Examples of howling

9 10

10 10

4 10

See example 1 3

See »Example 2 2

See example 3 3

See example 4 2

In the above sound quality and howling tests, the rubber sheets according to the invention (Examples 9 to 10) led to exceptionally good results compared with the conventional rubber plotters) (Comparative Examples 1 to 4) «

The rubber sheets of Examples 9 and 10 with A hardnesses 18 and _{P, respectively}

230609/0038

23 made it possible to reproduce much better-sounding tones than the rubber sheet according to Example 4 with a lower hurte out of 9 as A-hard.

(3) slip test

This test was carried out in the same manner as in Examples 1 to 4 carried out. As a result, it was found that the rubber sheets of Examples 9 and 10 were both suitable.

(4) lift test

This test was carried out on the same with the rubber sheet of Example 9 Way carried out as in Examples 1 to 4. As a result, it was obtained that the rubber sheet of Example 9 lifted up to 10 rubber sheets of Comparative Example 3 (weight 3.4 kg).

(5) scratch test

This test was carried out on the same with the rubber sheet of Example 9 Manner as carried out in Examples 1 to 4. As a result, it was obtained that on the rubber sheet of Example 9 after 30 There were faint scratches outwards, but these were caused by a one-off Rubbing with the finger could be removed without leaving a trace

(6) Dust Adhesion Test

The test was carried out in the same manner as in Examples 1 to 4 performed; As a result, there was practically none

2306U9 / 0038

~ ff 3049078

Ash remained on the rubber sheets of Examples 9 and 10. Examples 11 and 12

Rubber disks for a turntable were produced in the same manner as in Examples 1 to 4 except this time the rubber mixtures as indicated in Table 17 were changed.

The physical constants of the rubber sheets obtained
were measured in the same manner as in Examples 1-4. The results are given in Table 18.

Tobelle 17 Examples - 250 Rubber compound (in parts) 11 50 200 Components 250 50 - 230 - 1,000 Norsorex 150 NA 400 5 15th DOG Factice F 10 - 1 35 Sunthene 255 2 - Sundex 790 1
1.5
8th 50 Rapeseed oil 5 Dioctyl phthalate 1 FEF carbon 2 MT carbon 1
2.5
10 zinc oxide Stearic acid Antioxidant DDA Suntight S
sulfur
Suncollcr CZ

230609/0038

Table 18

^ Hardness (°) impact elastic tensile elongation specific

W Example ity (J0 stigkeit {%) Weight

S. C-Hdrte F-hardness (kg / cm)

CD 1 1 1 1 7 δ ό δ ό .5 δ87 0.977 O O 1 2 - δ 1 5 1 0 . δ 490 1.004

- * »- 3049378

With the rubber sheets of Examples 11 and 12, the following were made Tesisrdua-ch led;

(l) sound quality test

The test was carried out in the same way as in Examples 1 to 4, but this time the test record and the
Parameters were changed as follows i The results are given in Tables 19 and 20 together with the results obtained with
the rubber sheets of Example 2 and Comparative Examples 1 to 4 were obtained «

Test record

Record title: "0uv _3r ture 1312" by Tschaikovsky (Te-

~ larc Records) "

Performing: The Cincinnati Symphony Orchestra Conductor: Erich Kunzel Parameter:

(a) whether the sounds of a cannon were reproduced well,

(b) whether the high notes were not distorted,

(c) whether the bass was reproduced well,

(d) whether the presence indices were sufficient

230609/0038

Table 19

parameter

Cannon sounds

Distortion of high notes

Ba3

Presence imprint

Total assessment

Average rating

example Example 12 Example 2

THERE

5455 54555455

555555544555 5555 55545455

100 95 100 95 95 95 95 90 90 85 95 90

90

Table 20

See Example 1 See Example 2 See Example 3 See Example 4

co
ο parameters
co A. B. C. D. A. B. C. 45 D. A. B. 4th C. 1 D. A. B. C. 41 D. * O
^ Cannon Sounds 2 2 2 2 2 1 '2 2 1 2 2 1 1 2 2 2 co distortion
⁰⁰ of high notes
Bass 2
3 1
5 2
5 2
5 2
5 2
2 5
5 2
5 2
2 1
2 2
5 3
2 1
2 2
3 2
3 2
2 Prdsenzeindrock 5 4th 2 4th 2 2 1 2 5 2 3 2 3 2 2 2 W. Overall rating 50 50 45 55 45 55 45 45 40 55 50 40 35 45 45 40 O 1
) average
evaluation 50 CO j
i

" ⁷ Ij 3049378

(2) Howl test

The test was carried out in the same manner as in Examples 1 to 4 except that this time the test record was exchanged for the one used in the above sound quality test, and the test was carried out only in the case where the Rubber sheet having the surface l_dex with the projections (3) shown in FIG 1 to 4 were obtained

Table 21 Howl 3 3 Examples 10 2 11 9 12th 8th 2 4th Comparative example 1 Comparative example 2 Comparative example 3 Comparative example 4

In the above tone quality and howling tests, those of the present invention performed Rubber sheets (Examples 11 and 12) too exceptionally good Results compared with the conventional rubber sheets (comparative examples 1 to 4)·

The rubber plates of Examples U and 12 with a C hardness of 11

230609/0038

(F-hardness 73 °) or an F-Hörte of 31 prevented that Howling and enabled the reproduction of sounds of very low frequencies compared to the rubber sheet of Example 2 with a higher hardness of 5 than A-hardness «

(3) slip test

This test was carried out in the same manner as in Examples 1 to 4. As a result, it was found that cutnmiplates Examples 11 and 12 were both suitable "

(4) scratch test

This test was carried out on the same with the rubber sheet of Example 11 Manner as carried out in Examples 1 to 4. As a result, it was found that faint marks appeared after 30 hours, which, however, can be restored by rubbing it once with your finger removed without leaving a trace.

(5) Dust Adhesion Test

This test was carried out in the same manner as in Examples 1 to 4. As a result, it was obtained that is practical no ash adhered to the rubber sheets of Examples 11 and 12 stayed »

Step Example le 13 to 15

In the same manner as in Examples 1 to 4, rubber sheets were made made for a turntable, but this time the rubber mixture was changed as indicated in Table 22 below became·

230609/0038

3049378

The physical constants of the rubber sheets thus obtained were measured in the same way as in Examples 1 to 4. The results are given in Table 23.

Table 22

Rubber compound Components (in pieces) - Examples 1 1 15th 200 14th 2 Nipol SBR 1712 ,, 13 - mm - - Natural rubber 137.5 200 100 2.7 100 Baypren 112 (footnote 1) - 20th - 0.7 - DOG Factice F 10 5 250 0.4 240 DOG Factice NP 17 (footnote 2) - - - 200 Sunthene 255 1 110 - 45 MT carbon 2 50 - zinc oxide 1 5 4th Magnesium oxide 2 - 1 Stearic acid 4th 1 1 Antioxidant DDA - 1 Suntight S 2 sulfur - - Sunceller CZ - Nocceler DM (footnote 3) - - Nocceler D (footnote 4) Nocceler TT (footnote 5) 1/1 Nocceler DT (footnote ό) 1/1 Nocceler TS (footnote 7)

Footnote 1: Chloroprene rubber, manufactured by Bayer AG

230609/0038

Footnote 2: Amber colored sulfur factice made by

of the company DOG Deutsche Öl fabrik Ges ·. f. Chein. Ore.

mbH & Co.
Footnote 3: Vulcanization accelerator manufactured by the company

Ouchi Chemical Industry Co., Ltd * Footnote 4: Vulcanization cup made by the company

Ouchi Chemical Industry Co., Ltd, footnote 5; Vulcanization accelerator manufactured by the company

Ouchi Chemical Industry Co., Ltd · Footnote 6ί Vulcanization accelerator manufactured by the company

Ouchi Chemical Industry Co., Ltd » Footnote 7: Vulcanization accelerator manufactured by the company

Ouchi Chemical Industry Co., Ltd 230609/0038

Table 23

ο hardness () impact elastic, tensile, elongation specific

ο Example »did {%) stig- (j0 weight

^ Α hardness C hard F hardness ₂

ο (kg / cm)

σ

oo 13 9 50 - 62 8 258 1,009

14 25 51 - 62 5.4 225 0-984

15 - 10 69 45 5 - 6 522 1,026

-rf- 3049378 ff

The tests described below were carried out with the rubber sheets of Examples 13 to 15

(T) tone quality test

This test was carried out in the same manner as in Examples 1 to 4 performed. The results are in Tables 24-14 .26 specified

230609/0038

O CD O <£> *>. OO Cv>

• Poraraetex

Close to human voices

Distortion of high notes

Accompanying 'guitar

Presence impression total rating

Average rating

example

! Table '(feminine

example

AWAY

.'C

■ Β <C

-5-4 4 5 -4 '5 -4' 5

'5' 5 5 4 4 '5' 5

■ 5 5 '5 "5' 5 '5 4 Έ

^r 5 ^Γ 5 4 ^r 5 '5' 4 '5' 5

^! Example

'5 4 5 ^r 5

5 5 3
'5 5 ά 5

100 95 90 95 90 95 90 95 90 95 90 95

95 93

to

3049378

• Η

42

'ρ-

to

ok

to

Φ to

»Λ Μ") to
P- ίο
Ρ to \ f> Φ P- μ? to to
P- ίο
P- ^ "LO P- LO - ^ J- ΙΛ
P- ^ to ! /)
P- LO LO ©
Φ ^ - to P- tO LO ρ- to to to
Ρ 5 ^ · LO ίο
Ρ

I.

£ g c cq: o ο t CQ

jo Μ

t'ri

'8 8 p

230609/0038

Table , 26 (Flomenco guitar)

Parameter chord sounds

ο Distortion of the high % tones

Guitar strokes

Presence imprint

Total rating average

valuation

example Example 14

DAB

Example 15

5 5 9 1 6th 5 5 5 5 9 6th 5 5 5 5 9 5 4th 5 95 95 00 95 100 95 95 95 95 95 95 90

(2) Howl test

The test was carried out in the same way as in Examples 1 to, except that the test was carried out only in the case where the rubber sheet with the surface shown in Fig. 1 and the surface with the protrusions (3) with the record was in contact. The results of the test are shown in Table 27

Table 27 13th Examples
14th 15th vinyl record 8th
9
9 8th
8th
8th CO CO 00] Female vowel piece
Concert piece
Flamenco guitar

In the above sound quality and howling tests, those of the present invention performed Guratni plates (Examples 13 to 15) result in exceptionally good ones Effects compared with the conventional rubber sheets j_ Comparative Examples 1 to 4 (cf. Tables 5, 7, 9 and 10) J.

(3) slip test

This test was carried out in the same manner as in Examples 1 to 4 carried out «As a result, it was found that all of the rubber sheets of Examples 13 to 15 were suitable

(4) lift test

This test was carried out on the Guroin plate of Example 13 in the same manner as in Examples 1 to 4. As a result, it was found that the rubber plate of Example 13 had up to 6 rubber

230609/0038

ο, 3Cu:) <r / 8 ti

plates of comparative example 3 (weight 2.0 kg) lifted off

(5) scratch test

This test was carried out on the same with the rubber sheet of Example 13 Way carried out as in Examples 1 to 4. As a result, it was found that faint marks were made after 30 minutes, which, however, can be removed by rubbing them once with your finger could become.

(6) Dust Adhesion Test

This test was carried out in the same manner as in Examples 1 to 4. As a result, it was found to be practically none Ash adhered to the rubber sheets of Examples 13-15.

Examples 16-19

Rubber disks for a turntable were produced in the same manner as in Examples 1 to 4, but this time the rubber compounds as indicated in Table 28 were changed.

The physical constants of the rubber sheets obtained thereby became measured in the same manner as in Examples 1 to 4. The results are shown in Table 29.

230609/0038

Table 23 Rubber research (in parts)

Components 16 17th Examples 19th mm 137.5 - 18th - 2 Nipol SCR 1712 - 100 - - Nipol IR 2200 Wed 1 Nprdel 1040 (footnote l) - 100 100 Mllathone 76 (footnote 2) 230 200 - - DOG Factice F 10 250 200 DOG Factice NP 17 15th - DOG Factice DS-SOFT (footnote 3) 200 15th 250 Sunthene 255 - 70 200 - Sunpar 110 - - 10 Thiokol TP-95 (footnote 4) 5 em mm SRF carbon 60 «· - MT carbon 50 10 Light calcium carbonate 5 5 - - zinc oxide - _ 5 0.5 Zinc stearate 1 1 - Stearic acid 2 1 1 - Antioxidant DDA 1 1 1 - Suntight S 2 2, 1 1.5 sulfur 4th 2 2 2.5 - Sunceller CZ - Wed - 3 Nocceler DM - Nocceler TT - pa 1/2 Mocceler ΙΊ (footnote 5) - 2 Nocceler TRA (footnote 6) tm 1.2 Thiokol ZC 456 (footnote 7) -

230609/0038

Footnote 1: Ethylene-propylene-diene copolymer, manufactured by
Company EI DuPont de Nemours & Co *

Footnote 2: Urethane rubber manufactured by Technical Sales and Engineering Ine »

Footnote 3: Amber colored soft sulfur factice, made by the company DOG Deutsche Ol fabrik Gos. f. Chein. Ore mbH & Co.

Footnote 4: Softener manufactured by Thiokol Corp ·

Footnote 5: Vulcanization accelerator manufactured by the company Ouchi Chemical Industry, Co., Ltd »

Footnote ό: Vulcanization accelerator manufactured by the company Ouchi Chemical Industry Co., Ltd

Footnote 71 Vulcanization accelerator manufactured by Thiokol Corp.

230609/0038

Table

ω hardness () impact elasticity tensile strength elongation specific

ο Example Α-Hardness C-Heard ziiät {%) speed ₂ (#) Weight "* (kg / cm)

σ ο to

1 6 1 8 46 59 21st 564 1.010 1 7 8th 28 <$ 4 6th 330 0-921 18th 6th 25th 52 7th 241 0.971 1 9 4th 22nd 01 2 182 1, 008

.C-. CO CO

Like the rubber sheets of Examples 13 to 15, the rubber sheets of Examples 16 to 19 also allowed the reproduction of sounds in excellent sound quality

230 6 09/0038

Claims (1)

1) Rubber plotters for a turntable, which is a plate-shaped vulcanized molded body made of a rubber compound and having a hardness within the range of 30, measured with a Α-type rubber hardness tester, to 15, measured with a rubber hardness tester above F -Type, and has an impact resilience of not less than 40 % 2 »The rubber sheet according to claim 1, wherein the hardness is not more than 20 as measured with the Α-type gurami hardness tester and not less than 30 as measured with the F ~ _{-type rubber hardness tester /} and the impact resilience is not less than 50 % 3 «rubber plate according to claim 1, wherein the hardness be greater than 15, as measured by rubber hardness testing apparatus from Α type, and not more than 30 measured by the rubber hardness tester A type ₁ and the impact resilience of not less than 50% · 4 * rubber sheet according to claim 1, where the hardness is 1 to 15, measured with the A-type rubber hardness test device ₍ « The rubber sheet according to claim 1, wherein the hardness is less than 1 as measured by the A-type rubber hardness tester _/ and not less than
amounts to" Less than 15 as measured by the F-type rubber hardness tester, 6 · rubber sheet according to one of claims 1, 2, 3, 4 and 5, wherein the vulcanized molded body is a vulcanized molded body made of a rubber mixture, which predominantly contains polyynorbornene as the rubber component contains 230609/0038 7e rubber sheet according to one of claims J, 2, 3, 4 and 5, wherein the vulcanized molded body is a vulcanized molded body made of a rubber mixture, which is predominantly as a rubber component at least contains a representative selected from the group consisting of natural rubber, isoprene rubber, chloroprene gunimi, styrene-butadiene rubber, Butadiene rubber, butyl rubber, ethylene propylene guinmi, ethylene propylene diene rubber, Nitrile rubber, acrylic rubber, urethane rubber, chlorinated polyethylene, chlorosulfonated polyethylene, epichlorohydrin rubber ^ polysulride rubber and silicone rubber * 8 »rubber sheet according to claim 1, wherein the rubber mixture comprises (A) 100 parts by weight of a rubber component (B) 1 to 2000 parts by weight of a Factice and (C) 20 to 2000 parts by weight of a plasticizer. 9, rubber sheet according to claim 8, wherein the amount of component (ß) 5 to 200 parts by weight and the amount of component (C) 50 to 2000 Parts by weight. 10 »rubber sheet according to claim 9, wherein the amount of the component (B) 100 to 1500 parts by weight and the amount of component (C) 200 up to 1500 parts by weight. 11 »rubber sheet according to one of claims 8, 9 and 10, wherein the Component (A) predominantly contains polynorbornene. 12 »rubber sheet according to one of claims 8, 9 and 10, wherein the Component (A) predominantly contains at least one representative selected from the group consisting of natural rubber, isoprene rubber, chloroprene rubber, Styrene-butadiene rubber, butadiene rubber, butyl rubber, ethylene-propylene rubber, Ethylene propylene diene rubber, nitrile rubber, acrylic rubber, Urethane rubber, chlorinated polyethylene, chlorosulfonated poly- 230609/0 038 30A9378 Ethylene, chlorosulfonated polyethylene, epichlorohydrin rubber, polysulfide rubber and silicone rubber. The 13o rubber sheet of claim 1, wherein one surface of the body the gumrai plate is provided with a large number of protrusions. 14. The rubber sheet of claim 13, wherein at least the head of each the protrusions is in the form of a comb to essentially have a linear contact with a turntable or record to be given. 15. A rubber sheet as claimed in claim 13, wherein at least the head of each of the Projections is sharpened in order to give essentially a point-like contact with a turntable or a record 16. Rubber sheet according to one of claims 13, 14 and 15, wherein the Height of the projections is 0.1 to 5 mm «, 17. Rubber sheet according to claim 16, wherein the height of the projections is 0.3 to 1.8 mm © 18. Rubber sheet according to claim 13, wherein the projections close together are arranged in a plurality of concentric circular rows. 19. The rubber plate of claim 18, wherein at least the head of each the protrusions are in the shape of a comb to essentially oinen linearη contact with a turntable or a record to result in *. 20e rubber sheet according to claim 19, wherein the crests of the projections 230603/0038 - 96 - ο η ι Q c 7 Q aligned along the radial direction of the body of the rubber sheet are. 21 · Rubber plate according to claim 13, wherein at least the head of each of the projections is pointed to produce a substantially point-shaped contact with a turntable or a record ζυ · 22 · Rubber sheet according to one of claims 18, 19, 20 and 21, wherein the head of each protrusion in one of the concentric circular rows corresponding to a valley between two adjacent protrusions is arranged in the adjacent concentric circular row in the radial direction of the body of the rubber sheet. 23 · Gumraiplatie according to claim 22, wherein when so arranged is that it is in contact with the surface provided with the projections with a record and the other surface is in contact with a turntable, the protrusions are highest in the innermost concentric circular row and in the direction of the outer rows the projections gradually become lower and air is trapped inside a space the middle portion of the body of the rubber sheet, which is defined by the innermost concentric circular row of projections and the Record is limited. 24o rubber plate according to claim 23, v / o with the turntable contacting surface having a plurality of concentric circular grooves corresponding to the plurality of concentric ones circular rows of projections and that air is trapped in at least the innermost groove 230609/0038 3049378 25 »Rubber sheet according to claim 1, which is a sheet-shaped vulcanized molded body made of a rubber mixture containing (A) 100 parts by weight of polynorbornene alone or in the form of a mixture of the same with another rubber component, (B) 5 to 500 Parts by weight of white factice alone or in the form of a mixture of the same with another factice and (C) 200 to 1000 parts by weight of at least one oil selected from the group consisting of aromatic oils, naphthenic oils, paraffin oils, vegetable oils and animal oils, wherein the vulcanized molded body has a hardness of 1 to 15 as measured by the A-type rubber hardness tester, a tensile strength of 1 to 50 kg / cm, an elongation of 120 to 1000 %, an impact resilience of 40 to 90 % and has a specific gravity of 0.23 to 1.05, and a surface of the body of the rubber sheet is provided with protrusions 0.3 to 1.8 ram in height, which are in the form of a plurality of concentric circular rows n are arranged close to one another. 230609/0038