JPH085972B2 - Clutch facing manufacturing method - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to a method for manufacturing a clutch facing used in an automobile, an industrial machine or the like, and more specifically, a vibration phenomenon, that is, a judder phenomenon occurring when a clutch facing is connected is reduced. To a simple clutch facing manufacturing method.

Technical background of the invention and its problems Conventional clutch facings are based on asbestos as a base material, on which thermosetting resin such as phenol resin, rubber material, vulcanizing agent, vulcanization accelerator, friction improver, filler, etc. It has been manufactured by adhering a solution of a resin in a solvent, pre-molding it, and then heating and pressing it in a mold. However, in recent years, the adverse effects of asbestos on the human body have been pointed out, and clutch facings that do not contain asbestos have come to the forefront.

Clutch facings that do not use asbestos as a base material include thermosetting resin such as phenol resin, rubber material, vulcanizing agent, vulcanization accelerator, etc. attached to glass fiber as a base material, which is then preformed and then It is manufactured by heating and pressing with a mold. Such a clutch facing has been proposed, for example, in US Pat. No. 4,130,537. The clutch facings taught in this U.S. Pat.No. 4,130,537 are clutch facings obtained by using only glass fibers as a base material because the riding comfort is uncomfortable, so glass fibers such as rayon, hemp, and organic fibers such as cotton, Pre-composite with glass fiber, dip the obtained composite yarn in a solvent in which phenolic resin, rubber compound, other friction improver, etc. are dissolved or dispersed, and put these substances on the composite yarn. It is manufactured by applying it, then preforming it and then heating and pressing it.

By the way, a clutch facing obtained by using an inorganic fiber such as glass fiber as a base material or a combination of an inorganic fiber such as glass fiber and an organic fiber does not necessarily have a sufficient torque capacity, and has high horsepower or torque. There is a problem that it cannot exhibit sufficient performance when used in a large vehicle. In addition, the clutch facing as described above has a problem that a vibration phenomenon, that is, a judder phenomenon occurs when the clutch facing is connected, resulting in poor riding comfort.

By the way, in order to solve such problems,
No. 9526 discloses that a non-asbestos base material is mixed with organic fibers to form a sliver, which is then twisted, impregnated with a thermosetting resin, and then dried, molded, and cured to have a porosity of 5 to 5. Described is a method for producing a friction material, characterized in that the friction material is 25% by volume. In this publication, as a means for adjusting the porosity of the friction material to 5 to 25% by volume, the weight of the friction material is set to 5% more than the weight necessary for densely molding the mold having a constant volume so that the porosity is 0% by volume. A method of molding using 25% less weight is mentioned. Also, compared with the case of molding with a constant weight, the volume of the mold (thickness when the cross-sectional area is fixed) is 5 to 5 compared with the case of molding with a void volume of 0% by volume.
There is also a way to increase it by 25%.

However, in order to adjust the porosity of the clutch facing obtained by the above method, there is a problem that a plurality of expensive molds must be prepared according to the porosity of the clutch facing. In addition, since a thick molded product is made using a deep mold and the clutch facing is manufactured by polishing this, a large amount of material is discarded by polishing during polishing, which causes a problem of waste of material. there were.

The present inventors have conducted extensive studies to solve the above problems, and when producing a clutch facing, a base fiber, a thermosetting resin, and a rubber compound are used in a specific ratio, and If the amount of the curable resin is smaller than the amount conventionally used and is used in an amount of 10 to 25 parts by weight with respect to 100 parts by weight of the base fiber, the resulting clutch can be obtained depending on the amount of the thermosetting resin used. The porosity of the facing is changed, and the porosity of the obtained clutch facing is 2 to 15
The present invention has been completed by finding that the volume can be easily adjusted.

SUMMARY OF THE INVENTION The present invention is intended to solve the problems associated with the above-described conventional techniques, and has a large torque capacity and excellent judder resistance, and further has such excellent characteristics. It is an object of the present invention to provide a method for manufacturing a clutch facing that allows the clutch facing to be manufactured without preparing a plurality of expensive molds.

SUMMARY OF THE INVENTION The method for producing a clutch facing having a porosity of 2 to 15% by volume according to the present invention is a thermosetting resin after impregnating and adhering a thermosetting resin to a base fiber mainly composed of an inorganic fiber. When the resin is dried and then the rubber compound is adhered to the base fiber on which the thermosetting resin is adhered, the obtained material for forming the clutch facing is preformed and then heated and pressed to produce the clutch facing. ,
20 to 50% by weight of base fiber, 3 to 12% by weight of thermosetting resin
And a rubber compound in an amount of 40 to 65% by weight, and a thermosetting resin in an amount of 10 to 25 per 100 parts by weight of the base fiber.
It is characterized by being used in parts by weight.

In the clutch facing manufacturing method according to the present invention,
Porosity of clutch facing obtained by using base fiber, thermosetting resin and rubber compound in specific amounts respectively and using thermosetting resin in specific amount smaller than the conventional amount used for base fiber The rate is adjusted to 2 to 15% by volume, therefore the torque capacity is large and the resistance to judder is excellent, and it is not necessary to prepare a plurality of expensive dies.

DETAILED DESCRIPTION OF THE INVENTION A method for manufacturing a clutch facing according to the present invention will be specifically described below.

In the clutch facing manufacturing method according to the present invention,
By using each of the base fiber, the thermosetting resin and the rubber compound in a specific amount, and by using the thermosetting resin in a specific amount that is also small in the conventional use amount with respect to the base fiber,
The obtained clutch facing has a porosity of 2 to 15% by volume.
Each component is explained below.

Examples of the inorganic fiber used as the base fiber in the present invention include glass fiber, ceramic fiber, rock wool fiber, basalt fiber, calcium silicate fiber, serpentine fiber, carbon fiber and graphite fiber. In some cases, asbestos fibers can also be used. Of these, it is particularly preferable to use glass fiber. These inorganic fibers are yarn-shaped, roving-shaped, felt-shaped, ribbon-shaped,
It can be used as a tape.

Further, in the present invention, a small amount of organic fibers such as aromatic polyamide fibers, polyamide fibers, polyimide fibers, cotton, hemp, and rayon may be mixed with the above inorganic fibers and used.

Thermosetting resins and rubber compounds are used to bind the base fibers as described above.

As the thermosetting resin, phenol resin, urea resin,
Melamine resin, epoxy resin, etc. are used. Of these, a phenol resin is preferable, and as the phenol resin, a novolac type, a resol type, an aqueous solution type, or an alcohol solution type is used.

The rubber compound is generally composed of a rubber material, a vulcanizing agent, a vulcanization accelerator, a friction improver and the like.

Butadiene rubber (BR), styrene-
Butadiene rubber (SBR), isoprene rubber (IR), ethylene-propylene rubber (EPM), butyl rubber (IR), chloroprene rubber (CR), acrylonitrile-butadiene rubber (NBR), chlorosulfonated polyethylene (CSM),
Synthetic rubber such as acrylic rubber (ACM), urethane rubber (U), silicone rubber (Si), fluororubber (EPM), polysulfide rubber (T), polyether rubber (POR) and natural rubber may be used. Particularly preferred are styrene-butadiene rubber (SBR) and acrylonitrile-butadiene rubber (NBR).

As the vulcanizing agent, sulfur, zinc oxide, magnesium oxide, peroxide, dinitrosobenzene, etc. are used.
As the vulcanization accelerator, thiazole accelerator, polyamine accelerator, sulfenamide accelerator, dithiocarbamate accelerator, aldehyde amine accelerator, guanidine accelerator, thiourea accelerator, xanthate accelerator. A promoter or the like is used.

As the friction improver, clay, talc, barium sulfate, cashew dust, graphite, lead sulfate, tripolylith (siliceous limestone) and the like are used.

If necessary, an organic fiber may be added to the rubber compound in order to improve the processability of the rubber compound. As the organic fiber, a fiber having high heat resistance and flexibility is preferable, and specifically, natural fibers such as hemp, cotton, wool and silk and rayon, acetate, acetic acid staple, polyamide fiber (nylon etc.), Synthetic fibers such as polyvinyl alcohol fibers (such as vinylon), polyacrylic fibers, polystyrene fibers, phenol resin fibers, and aramid fibers can be used.

The organic fiber added to the rubber compound has a fiber diameter of 5 to 60 μm.
m preferably 10 to 40 μm, length 1 to 50 mm, preferably 3 to
It is desirable to use a material having an aspect ratio (length / diameter) of 10 mm in the range of 200 to 5000, preferably 200 to 1000, in order to improve the processability of the rubber compound. If the length of the organic fiber is too long, the dispersibility in the rubber compound is deteriorated, which is not preferable.

The organic fiber is added to the rubber compound in an amount of 1 to 15% by weight, preferably 1 to 9% by weight, more preferably 1 to 5% by weight, based on the weight of the rubber compound. If the amount of the organic fiber added exceeds 15% by weight, it is not preferable because the organic fiber is melted or carbonized due to the frictional heat generated during the use of the clutch facing to lower the friction coefficient of the clutch facing. This is not preferable because the processability of the compound does not improve so much.

In the present invention, in the method for producing a clutch facing as described above, the base fiber is 20 to 50 wt%, preferably 25
-40% by weight, thermosetting resin in an amount of 3-12% by weight, preferably 5-10% by weight, and rubber compounding in an amount of 40-65% by weight, preferably 45-60% by weight. Used in an amount of.

And in the present invention, the thermosetting resin within the above range,
10 to 25 parts by weight per 100 parts by weight of the base fiber, preferably 15
Used in an amount of ~ 23 parts by weight. The amount of such thermosetting resin is smaller than the amount conventionally used.

Thus, when manufacturing the clutch facing, the porosity of the obtained clutch facing can be increased by reducing the amount of the thermosetting resin as compared with the conventional one. For example, when 21 to 6 parts by weight of phenol resin is used for 100 parts by weight of glass fiber, the porosity of the obtained clutch facing is 6.5%, and 20 parts of phenol resin for 100 parts by weight of glass fiber, When 8 parts by weight is used, the porosity of the obtained clutch facing reaches 14.5%.

On the other hand, when 44.9 parts by weight of phenol resin was used with respect to 100 parts by weight of glass fiber, the porosity of the obtained clutch facing was 1.2%.
When 40.9 parts by weight of phenolic resin is used with respect to 00 parts by weight, the porosity of the obtained clutch facing is 0.8.
%.

In the present invention, the porosity of the obtained clutch facing is adjusted to 2 to 15% by volume by using the base fiber, the thermosetting resin and the rubber compound in the above range. Is more than 15% by volume, the burst strength of the clutch facing is significantly reduced and the torque capacity is also reduced, which is not preferable. Further, if the porosity is less than 2% by volume, clutch facings having a high burst strength can be obtained, but the torque capacity is small and the resistance to judder is poor, which is not preferable.

Next, the clutch facing according to the present invention can be manufactured by a conventionally known manufacturing method, and one example of the manufacturing method will be described more specifically.

First, a thermosetting resin is impregnated and adhered to a string-shaped base fiber fiber obtained by integrating a plurality of linear inorganic fibers such as yarn-like or roving-like, and then the thermosetting resin is applied to about 90 Dry at a temperature of ~ 120 ° C and then apply the rubber compound to the base fiber. As a method for adhering the rubber compound, for example, a rubber compound formed in a sheet shape may be adhered, or the rubber compound may be dissolved in a solvent to form a rubber paste, and the base fiber is immersed in the rubber compound, It may then be dried and applied.

The material for forming the clutch facing thus obtained is wound around a preforming die and preformed into an annular shape of a predetermined size, and the preform is subjected to 150 to 200 kg.
The clutch facing according to the present invention is obtained by heating and pressurizing at a temperature of about 150 to 180 ° C. with a pressure of f / cm ² .

Effects of the Invention In the method for manufacturing the clutch facing according to the present invention,
Pore for clutch facing obtained by using base fiber, thermo-effective resin and rubber compound in specific amounts respectively and using thermosetting resin in a specific amount smaller than the conventional amount used for base fiber The rate is adjusted to 2 to 15% by volume, therefore the torque capacity is large and the resistance to judder is excellent, and it is not necessary to prepare a plurality of expensive dies.

Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited thereto.

Example 1 A glass roving was used as the inorganic fiber, and the glass roving was immersed in a container filled with a phenol-formaldehyde resin solution, and the glass roving (66% by weight) was mixed with the phenol resin (14% by weight) and the solvent ( 20
Wt%) was impregnated and deposited. Then, the glass roving impregnated with the phenol resin was dried at a temperature of 90 to 120 ° C., and then the rubber compound (I) having the following composition was put between the grooved rolls so that the roving was sandwiched from the upper and lower sides. It was supplied and the sheet-shaped rubber compound was adhered to the roving to obtain a material for clutch facing. In this clutch facing material, glass roving was included in an amount of 58% by weight, and rubber compound (I) was included in an amount of 42% by weight.

Composition of rubber compound (I) NBR rubber 30% by weight Filler 62% by weight Vulcanizing agent 8% by weight Next, the thus obtained material for clutch facing is wound around a preforming mold, and Pre-formed into a circular ring of size, transfer it to the molding die, and leave at 160 ℃
At a temperature of 180 kgf cm ² for 5 minutes to vulcanize and cure. Further, it was heat-treated at a temperature of 170 ° C. for 5 hours to produce an annular clutch facing having an outer diameter of 200 mm, an inner diameter of 130 mm and a thickness of 3.5 mm.

The porosity of the obtained class facing was measured and found to be 6.5% by volume.

The porosity of the obtained clutch facing was measured using the "porosity test method" of the automotive standard JASO C444 "Brake lining, pad physical property test method".

In addition, when the torque capacity test of the clutch facing obtained as described above was conducted, 20 times out of 20 times passed, and it was found that the torque capacity was sufficiently large.

The torque capacity of the obtained clutch facing was measured as follows.

Attach the clutch facing to the passenger car and stop the car on a flat surface.

The transmission gear is neutral and the engine speed is 4,000.
Raise it to 0 rpm and keep it there.

Disengage the clutch and shift gear into third gear.

While continuing to step on the accelerator pedal, quickly engage the clutch and start the car suddenly.

Apply the brakes to stop the car and keep the engine running at 2,000 rpm for 30 seconds with the clutch disengaged.

Repeat the above steps to make a total of 20 sudden starts.

When the clutch was immediately engaged and the vehicle could start rapidly after 20 times, it was evaluated that there was sufficient torque capacity, that is, the torque capacity was high.

When the clutch started to slip from a certain number of times in 20 repeated evaluations (it took 3 seconds or more before the clutch was engaged after the foot was released from the clutch pedal), the test was rejected at that number of times.

The burst strength of this clutch facing is 1
It was 4,000 (rpm).

Example 2 A clutch facing was manufactured in the same manner as in Example 1 except that glass yarn was used instead of glass roving, and the amount of the phenolic resin deposited was changed as follows.

However, 14% by weight of a phenol resin and 19% by weight of a solvent were impregnated and adhered to 67% by weight of a glass yarn and then dried, and then 49% by weight of a rubber compound was adhered to 51% by weight of this yarn.

The porosity of the obtained clutch facing was measured and found to be 4.3% by volume.

Further, when the torque capacity test of the obtained clutch facing was conducted, 20 times out of 20 times passed, and it was found that the torque capacity was sufficiently large. The burst strength of this clutch facing is 13,600 (rp
m) was.

Example 3 In the same manner as in Example 1, except that glass bulky yarn (bulk roving subjected to bulking) was used in place of glass roving, and the amount of the phenolic resin deposited was changed as follows. To produce a clutch facing.

However, to 65% by weight of glass bulky thread, 14% by weight of phenol resin and 21% by weight of solvent were impregnated and adhered and then dried, and then 55% by weight of rubber compound was adhered to 45% by weight of this bulky thread. .

The porosity of the obtained class facing was measured and found to be 14.5% by volume.

Further, when the torque capacity test of the obtained clutch facing was conducted, 20 times out of 20 times passed, and it was found that the torque capacity was sufficiently large. The burst strength of this clutch facing is 13,700 (rp
m) was.

Comparative Example 1 A clutch facing was manufactured in the same manner as in Example 1 except that the amounts of the phenolic resin and the rubber compound attached to the glass roving were changed as described below.

However, 21% by weight of a phenol resin and 32% by weight of a solvent were impregnated and adhered to 47% by weight of glass roving and then dried, and then 29% by weight of a rubber compound was adhered to 71% by weight of this glass roving.

The porosity of the obtained class facing was measured and found to be 1.2% by volume.

When the torque capacity test of the obtained clutch facing was conducted, it failed at the 11th time and the torque capacity was not so large. The burst strength of this clutch facing was 13,700 (rpm).

Comparative Example 2 A clutch facing was manufactured in the same manner as in Example 1 except that the amounts of the phenolic resin and the rubber compound attached to the glass roving were changed as described below.

However, 20% by weight of a phenol resin and 31% by weight of a solvent were impregnated and adhered to 49% by weight of glass roving and then dried, and then 69% by weight of a rubber compound was adhered to 31% by weight of this glass roving.

The porosity of the obtained crash facing was measured and found to be 0.8% by volume.

When the torque capacity test of the obtained clutch facing was conducted, it failed in the 8th time and the torque capacity was not so large. The burst strength of this clutch facing was 14,200 (rpm).

Comparative Example 3 A clutch facing was manufactured in the same manner as in Example 1 except that the amounts of the phenolic resin and the rubber compound attached to the glass roving were changed as described below.

However, with respect to 76% by weight of glass roving, 10% by weight of a phenol resin and 14% by weight of a solvent were impregnated and dried, and then dried, and then 47% by weight of a rubber compound was adhered to 53% by weight of this glass roving.

The porosity of the obtained class facing was measured and found to be 18% by volume.

When the torque capacity test of the obtained clutch facing was conducted, it failed at the 18th time and the torque capacity was not so large. The burst strength of this clutch facing was 10,600 (rpm).

 The results are summarized in Table 1.

Claims (1)

[Claims] 1. A base fiber mainly composed of inorganic fibers is impregnated with a thermosetting resin, and then the thermosetting resin is dried, and then the base fiber is adhered with the thermosetting resin. After the rubber compound is adhered, the material for forming the clutch facing is preformed and then heated and pressed to produce the clutch facing.
~ 50 wt%, 3-12 wt% thermosetting resin and 40-65 wt% rubber compound, and 10
A method for producing a clutch facing having a porosity of 2 to 15% by volume, which comprises using 10 to 25 parts by weight of a thermosetting resin with respect to 0 part by weight.