JP2000065109A - Doughnut plate-like friction plate and manufacture therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve productivity and a material yield, and to enhance qualitative stability by manufacturing a pipe-shaped mold by extrusively molding a friction material raw material, and obtaining a doughnut-shaped mold by successively cutting this pipe-shaped mold at a right angle in the lengthwise direction at a prescribed thickness dimension pitch. SOLUTION: In a first step n1, a pellet-like friction material raw material is manufactured. In a second step n2, this pellet-like friction material raw material is supplied to a kneading extruder to manufacture a pipe-shaped mold by extrusion molding. In a third step n3, the obtained pipe-shaped mold is successively cut at a right angle in the lengthwise direction at a prescribed thickness diemsion pitch to obtain a doughnut plate-like friction plate. In a fourth step n4, a doughnut plate-like mold obtained by slice work is heat-treated, an unhardened thermoplastic resin component contained in the doughnut plate-like mold is hardened, and a rubber component is vulcanized at the same time to thereby obtain the doughnut plate-like friction plate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a friction plate used for clutches and brakes in various fields and a method of manufacturing the same, and more particularly, to a friction plate used for an electromagnetic clutch of a compressor for a car air conditioner. The present invention relates to a donut plate-shaped friction plate which can be particularly preferably applied to a friction plate having a small difference in inner and outer diameters, and a method of manufacturing the same.

[0002]

2. Description of the Related Art An outline of a conventional method of manufacturing a friction plate of this kind is as shown in FIG. That is, heat-resistant organic fibers represented by aramid fibers, glass fibers, natural inorganic fibers,
Add thermosetting resin typified by phenol resin as binder component to fiber components such as metal fiber and powder filler components such as barium sulfate, calcium carbonate, cashew dust, cork powder, graphite, molybdenum disulfide, etc. The raw material is used as a raw material, and the raw material is stirred and mixed. The raw material is press-formed at room temperature (preliminary forming) into a donut plate, and then subjected to heat-press forming (final forming), and then subjected to a heat treatment step to be machined. Produces a donut-shaped friction plate having a predetermined size.

More specifically, since the raw material of the friction plate contains a large amount of fibrous substances as described above,
A material obtained by stirring and mixing these raw materials (hereinafter, abbreviated as a friction material raw material) is a material which is very bulky due to entanglement of fibers, has no free flow property, and is extremely difficult to handle.
Since it is difficult to put this as it is into a heated molding die and uniformly fill it, pre-forming before heat-pressing, that is, pre-press-forming into a donut plate shape at normal temperature A process is introduced and this is called a preforming process.

[0004] In this preforming step, a friction material equivalent to one friction plate is weighed, put into a preforming die at room temperature, and uniformly filled into a donut plate by a running-in operation in the die. At the same time, a high pressure is applied by a preforming press to compress the bulky friction material into a compact, easy-to-handle donut plate-shaped preform.

[0005] In the main molding step, the preformed products are put into a heated main molding die one by one, and the thermosetting resin as a binder material is cured while being pressed by a main molding press. Of friction plate material.

In the heat treatment step, the friction plate material is heated in an oven to increase the degree of hardening, thereby improving the characteristics as a friction plate. In the machining step, the functional surface used as a friction surface is a resin surface due to resin richness as it is molded, and cannot be used in terms of friction performance. For this reason, the surface is removed and finished to a predetermined thickness, and the inner and outer diameters are processed as necessary.

[0007]

As described above, in the production of the friction plate, a stirring and mixing process of raw materials, a preforming process,
Many steps such as a main forming step, a heat treatment step, and a machining step are required. Although it is a problem that a large number of steps are required, individual steps also have the following problems.

First, in the preforming step, there is a problem in that a friction material material equivalent to one friction plate is measured. As described above, the friction material is very bulky due to the entanglement of the fibers and has no free-flow property, so that it is difficult to measure it economically with high accuracy. Inevitable. If the weight of the preform varies, it affects the main molding in the next step, and the quality of the friction plate varies.

[0009] Further, like an electromagnetic clutch friction plate mounted on a compressor for a car air conditioner, it has a donut plate shape.
In addition, when the difference between the inner and outer diameters is small (15 mm or less), the opening of the preforming mold is inevitably small, so that it is difficult to efficiently supply the bulky friction material to the preforming mold. Even if it is possible, it is almost impossible to perform uniform filling by a running-in operation in a mold. In such a case, an oversized friction plate material in which the difference between the inner and outer diameters is unnecessarily large is made, and the inner and outer diameters are finished to predetermined dimensions by punching, machining, or other methods. It requires wasteful use of friction material raw materials, wasteful finishing, and wasteful processing waste.

Next, since the steps of preforming and main forming are basically batch forming one by one, productivity is improved, that is,
In order to increase the number of moldings per hour, a large number of compression molding presses and dies for pre-molding and main molding are required, and economic production is difficult.

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above problems, and has as its object to provide a donut plate-shaped friction plate which has remarkably improved productivity and material yield and has excellent quality stability, and a method of manufacturing the same. is there.

[0012]

Means for Solving the Problems In order to achieve the above object, of the present invention, the invention according to claim 1 comprises a fiber component, a powdery filler component, a thermosetting resin component, and an unvulcanized rubber. Stir and mix, melt-knead this mixture using a kneading device,
A first step of forming a pellet-shaped or granular friction material material having a predetermined size, and supplying the pellet-shaped or granulated friction material material to a kneading and extruding apparatus, and continuously forming the pipe-shaped material by extrusion. A second step of manufacturing a molded article, a third step of sequentially cutting the molded article at a predetermined pitch in the longitudinal direction at right angles to the longitudinal direction to form a donut plate, and a molded article cut into the donut plate shape A heat treatment is performed to cure the uncured thermosetting resin component contained in the donut plate-like molded product and simultaneously vulcanize the rubber component.
And step.

According to the above construction, a pipe-shaped molded body is manufactured by extruding a raw material of friction material, and the pipe-shaped molded body is sequentially cut at a predetermined pitch in the thickness direction at a right angle in the longitudinal direction to form a donut plate. The body is obtained. Therefore, it is not necessary to preform and form each piece one by one with a compression molding press as in the prior art, but to form continuously with a kneading extruder, eliminating the need to measure the friction material material one by one. In addition, the difficulties and variations in the measurement due to the measurement can be solved at once, and it is possible to always obtain a donut-shaped friction plate having stable quality.

Further, according to the present invention, since the inner and outer diameters can be easily formed into predetermined dimensions, finishing of the inner and outer diameters becomes unnecessary.

In addition, the pipe-shaped molded article according to the present invention can easily perform ideal slicing with little cutting margin loss, and can be cut into any thickness with sufficient cutting surface conditions as a functional surface of the friction plate. Can also be used without performing. Accordingly, the amount of machining waste can be reduced to almost zero, and it is possible to contribute to preventing waste of the friction material.

Further, according to the present invention, as compared with the conventional method, the number of manufacturing steps can be greatly reduced, the complexity of the process management and the cost required for the process can be reduced, and a more inexpensive friction plate can be obtained.

Furthermore, the friction plate according to the present invention is useful for improving the performance as a friction material in addition to the effect as a binder by the kneading action of the unvulcanized rubber during extrusion molding. Therefore, a friction plate having better friction and wear characteristics can be obtained.

Further, according to the present invention, the fiber component, the powdery filler component, the thermosetting resin component, and the unvulcanized rubber are stirred and mixed, and the mixture is melt-kneaded using a kneading apparatus.
A first step of forming a pellet-shaped or granular friction material material having a predetermined size, and a storage tank for storing the pellet-shaped or granulated friction material material, wherein the stored pellet-shaped or granulated friction material material is stored. A storage tank provided with a first stirring means for stirring a friction material material in a shape, a supply unit for sequentially dropping and supplying a predetermined amount of a pellet-shaped or granular friction material material to a hopper of a kneading and extruding apparatus, and a storage tank A sensor for detecting the supply amount of the friction material raw material from the storage tank and a second stirring means for stirring the friction material raw material, and the supply unit while stirring the friction material raw material supplied from the storage tank by the second stirring means. And a communication pipe having one end communicating with the storage tank and the other end communicating with the storage section of the supply machine, and extending in the pipe axis direction in the pipe. And responds to the output of the sensor And a connecting pipe in which a continuous spiral body driven by the feeding device is provided, and the pellet-like or granular friction material material stored in the storage tank is clogged through the supply device. A second step of continuously producing a pipe-shaped molded product by extrusion molding without supplying a predetermined amount to a hopper of a kneading and extruding apparatus, and forming the pipe-shaped molded product at a predetermined thickness pitch at a right angle to a longitudinal direction. A third step of sequentially cutting into a donut plate shape, and heat treating the molded product cut into the donut plate shape to cure the uncured thermosetting resin component contained in the donut plate shape. And a fourth step of vulcanizing the rubber component.

According to the above configuration, the amount of the friction material supplied from the storage tank is controlled by the sensor provided in the supply device, and the stored amount of the friction material material is always constant in the storage section of the supply device. Has been maintained. Further, the friction material is continuously stirred by the first and second stirring means. Therefore, the friction material materials do not adhere to each other. As a result, a predetermined amount of the friction material is supplied to the hopper of the kneading and extruding apparatus without clogging, and a friction plate having a uniform density can be obtained.

According to a third aspect of the present invention, in the method for manufacturing a donut plate-shaped friction plate according to the first or second aspect, the mixing amount of the unvulcanized rubber is reduced during the first step. It is characterized in that it is 10 to 30% by weight based on the whole material.

If the amount of the unvulcanized rubber is too large, the friction coefficient of the friction plate becomes too large, which may impair the normal function of a product incorporating the friction plate, such as a clutch or a brake. If the amount of the unvulcanized rubber is too small, the moldability deteriorates.

According to a fourth aspect of the present invention, there is provided a donut plate-shaped friction plate manufactured by the method according to any one of the first to third aspects, wherein one of the two surfaces constituting a friction surface is formed. An adhesive is applied to the surface, and the adhesive is dried to a touch-dry state.

By applying an adhesive to one surface of the friction plate in advance as in the above configuration, the operation of applying the adhesive can be omitted at the assembly site of a device to which the friction plate is mounted. .

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a process chart for manufacturing a friction plate according to the present embodiment. The friction plate according to the present invention is a donut plate-like friction plate used for clutches and brakes in various fields, and is basically manufactured by the following steps. That is, a step of producing a pellet-shaped or granular friction material (hereinafter, referred to as a first step n1), and a step of molding the friction material produced in the first step n1 into a pipe-shaped compact by extrusion. (Hereinafter referred to as a second step)
Step n2), a step of slicing the pipe-shaped body to obtain a donut plate-shaped body having a predetermined thickness (hereinafter, referred to as a third step n3), and heat-treating the donut plate-shaped body. A step of curing the uncured thermosetting resin component and simultaneously vulcanizing the rubber component (hereinafter, referred to as a fourth step n4) produces a donut plate-shaped friction plate. Below, for each manufacturing process,
This will be described in detail together with the apparatus used.

(First Step n1) In a first step n1, a pellet-shaped friction material material is produced. Specifically, first, the fiber component, the powdery filler component, the thermosetting resin component, and the unvulcanized rubber are stirred and mixed. Next, the stirred and mixed mixture is melt-kneaded using a kneading apparatus to obtain a pellet-shaped friction material material having a predetermined size.

It is also possible to obtain a friction material raw material having a smaller particle size than the pellet shape. Also,
The kneading device may be any commonly used kneading device, such as a single-shaft kneading device, a twin-shaft kneading device, or a roll kneading device.

The fiber component functions to reinforce, and examples of the fiber component include heat-resistant organic fibers represented by aramid fibers, glass fibers, natural inorganic fibers, and metal fibers. Further, the powdery filler component is for fulfilling a function for improving friction and wear characteristics, and as the powdery filler component, barium sulfate, calcium carbonate, cashew dust, cork powder,
Examples include graphite and molybdenum disulfide. The thermosetting resin component serves as a binder,
Examples of the thermosetting resin component include a phenol resin. The unvulcanized rubber has a function of adjusting the hardness of the auxiliary binder and the friction material as a whole, and examples of the unvulcanized rubber include nitrile rubber.

The content of each component of the friction material raw material is, for example,
43% by weight of fiber component, 25% by weight of powdery filler component, 12% by weight of thermosetting resin component, 20% of unvulcanized rubber
% By weight. Here, it is desirable that the mixing amount of the unvulcanized rubber is set in a range of at least 10 to 30% by weight based on the entire friction material raw material. In particular, it is optimal to be 20% by weight.

The reason why the mixing amount of the unvulcanized rubber is regulated as described above is as follows. That is, if it is less than 10% by weight, extrusion cannot be performed in the subsequent second step n2. This is because the friction material raw material inherently has a low binder component and a large amount of a fiber component and a filler component. On the other hand, by mixing the unvulcanized rubber with the raw material of the friction material in advance, the unvulcanized rubber acts as a binder component, so that a pipe-shaped molded body can be obtained by extrusion molding. Become. Therefore, if the mixing amount of the unvulcanized rubber is too small, extrusion molding is impossible, or a molded body having no sufficient bonding force is obtained even if the mixing is not possible.

On the other hand, if the content exceeds 30% by weight, (1) the friction coefficient of the friction plate becomes too large, which may impair the normal function of a product incorporating the friction plate, such as a clutch or a brake. is there. That is, if the mixing amount of the unvulcanized rubber is too large, the friction plate adheres to the surface to be rubbed (the mating surface of the friction plate) due to the properties of rubber, thereby impairing the function of the clutch and brake itself. This is because there is a fear. (2) Further, when the unvulcanized rubber is mixed, the mixing amount of the fiber component and the filler component with respect to the entirety is reduced by the amount of the mixed rubber, so that the friction performance is lowered.

For reference, if the mixing amount of the thermosetting resin is increased in place of the unvulcanized rubber, extrusion molding can be performed, but the hardness of the pipe-shaped molded body obtained by extrusion molding is reduced. It becomes too large to perform slicing.

Therefore, the criteria for determining the mixing amount of the unvulcanized rubber are determined from three points, that is, the function as a binder, the softness when cutting the molded body, and the fact that the molded body has a predetermined friction coefficient. It is necessary to use an optimal amount. still,
The standard of the softness required for the molded body is 60 to 80 as indicated by a spring hardness meter (model SHORED).
It is about.

According to the experimental results of the present inventors, the optimum result was obtained at 20% by weight in the above range.

(Second Step n2) In the second step n2, the above-described pellet-shaped friction material is supplied to a kneading and extruding apparatus, and the pipe-shaped molded body 10 shown in FIG. 2 is continuously manufactured by extrusion. .

FIG. 3 is a simplified cross-sectional view of an apparatus used in the manufacturing process of the compact, FIG. 4 is an enlarged cross-sectional view of the tip of the kneading and extruding apparatus, and FIG. 5 is an arrow A in FIG. It is -A sectional drawing. The device 20 includes a screw 64
, A storage tank 22 for storing pellet-shaped friction material, a feeder 23 for sequentially dropping and supplying a predetermined amount of pellet-shaped friction material to a hopper 21a of the kneading-extruder 21, And a communication pipe 24 for transporting a predetermined amount of the pellet-shaped friction material stored in the storage tank 22 to the feeder 23. The communication tube 24 is a flexible tube, one end of which communicates with the storage tank 22, and the other end of which communicates with the storage part 23 b of the feeder 23. This communication pipe 2
Inside 4, a continuous helical linear body 25 extending in the tube axis direction is provided. The continuous spiral wire 25 is configured to be driven to rotate by a motor (not shown). Due to the rotation of the continuous spiral wire 25, the pellet-shaped friction material in the storage tank 22 advances in the communication pipe 24,
It is transported to the storage part 23b of the feeder 23. In the storage tank 22, a first stirring means 30 is provided. The stirring operation of the first stirring means 30 prevents the pellet material or granular friction material material in the storage tank 22 from sticking together and aggregating.

The feeder 23 supplies a predetermined amount of the pellet-like friction material to the hopper 21a of the kneading and extruding device 21 and supplies the pellet-like friction material from the storage tank 22 temporarily. And a storage unit 23b that stores the data in the storage unit 23b. The storage section 23b is provided with a level sensor 31, and the level sensor 31 is configured to detect the storage amount of the friction material material. For example, when the storage amount of the friction material material in the storage part 23b becomes equal to or less than a predetermined amount, the fact is detected by the level sensor 31. In response to the detection result from the level sensor 31, a motor (not shown) is driven for a certain period of time, and the continuous spiral linear body 25 is driven.
Is driven to rotate. Thereby, the friction material is stored in the storage tank 2
A fixed amount is supplied from 2 to the storage unit 23b. By providing the level sensor 31 in this manner, the stored amount of the friction material in the storage section 23b can be constantly maintained at a constant amount. As a result, it is possible to prevent a situation in which the amount of the friction material stored in the storage section 23b is too large and the friction material is stuck to each other.

A second stirring means 32 for stirring the friction material is provided in the storage section 23b. This second
The friction material is supplied to the supply section 23a while being stirred by the stirring means 32. Therefore, in combination with the constant storage amount by the level sensor 31, a predetermined amount of the friction material can be supplied to the hopper 21a of the kneading and extruding device 21 via the supply section 23a. Thus, in the extrusion molding system according to the present embodiment,
The friction material raw material stored in the storage tank 22 is supplied to the feeder 23.
The friction material can be supplied to the kneading / extruding apparatus with high precision by the action of the level sensor 31, the first stirring means 30, 32, etc. As a result, since a fixed amount is supplied without clogging, the density of the extruded molded body is extremely high. Therefore, the donut plate-shaped friction plate obtained by the subsequent slicing process can obtain a good quality product with no variation in density. This also improves wear resistance.

(Third Step n3) In a third step n3, the pipe-shaped molded body 10 is sequentially cut at a predetermined pitch in the thickness direction at right angles in the longitudinal direction, and the donut-shaped friction plate 50 is cut.
(See FIGS. 7 and 8).

FIG. 6 is a perspective view of a slice processing apparatus used in the manufacturing process of the third step n3. The slicing apparatus 40 has a rotating shaft 41, a rubber mounting pipe 42 fixed at one end to the rotating shaft 41, and a rotating blade 43 for cutting the pipe-shaped molded body 10. The rotary shaft 41 is hollow, and air is pumped from a compressor (not shown) into the pipe. A large number of air blowing holes 43 are formed in a portion of the rotating shaft 41 where the mounting tube 42 is mounted.
The inner diameter of the mounting pipe 42 is slightly larger than the outer diameter of the rotating shaft 41, and therefore, the mounting pipe 42 is loosely mounted on the rotating shaft 41. At the time of slicing, the pipe-shaped molded body 10 is gently sheathed on the mounting pipe 42. Then, in this state, air for pressure-feeding the inside of the rotary shaft 41 is blown out from the blow-out hole 43, and
Bulges in the radial direction, and the outer peripheral surface of the mounting pipe 42 and the inner peripheral surface of the molded body come into contact with each other, whereby the molded body is chucked to the rotating shaft 41 via the mounting pipe 42. In this manner, by chucking the compact on the rotating shaft 41, it is not necessary to directly chuck the compact, and therefore, it is possible to perform the slicing process over the entire length of the compact, thereby eliminating waste of friction material. be able to.

Next, the rotary shaft 41 and the rotary blade 43
Is driven to rotate. Further, the rotary blade 43 advances and retreats to the pipe-shaped molded body 10 and moves a predetermined pitch in the axial direction of the pipe-shaped molded body 10, whereby the pipe-shaped molded body 10 is sequentially sliced along the axial direction.

In this slicing, since the pipe-shaped molded body 10 is soft, little or no processing waste is generated.

Further, in the friction plate 50 obtained by cutting the pipe-shaped molded body, as shown in FIGS. 7 and 8, the outer peripheral surface 50a and the inner peripheral surface 50b are resin surfaces rich in resin. The cut surface 50c of the pipe-shaped molded body is a friction function surface. Therefore, unlike the related art, it is not necessary to grind the resin surfaces protruding on both side surfaces of the friction plate, and the step of grinding the resin surfaces in the manufacturing process can be omitted. Furthermore, in the present invention, in order to obtain a friction plate, it is necessary to cut the pipe-shaped molded body, but by this, together with the cutting, the surface accuracy of the cut surface is sufficiently increased, so that secondary machining is unnecessary. There is also an effect that becomes.

(Fourth Step n4) In the fourth step n4, the donut plate-like molded product 5 obtained by slicing
0 is heat-treated to cure the uncured thermosetting resin component contained in the donut plate-like molded body 50 and at the same time vulcanize the rubber component. As a result, a donut plate-shaped friction plate is obtained.

After the heat treatment step, an adhesive is applied to one of the two surfaces of the friction plate that constitutes the friction surface,
This adhesive may be dried to the touch-dry state. This eliminates the need to apply an adhesive to one surface of the friction plate in order to fix the friction plate to the device at the assembly site of the device to which the friction plate is to be mounted. improves.

(Other Matters) In the above embodiment,
Although the kneading and extruding apparatus having the die head 60 shown in FIGS. 4 and 5 is used, a kneading and extruding apparatus having the die head 60A shown in FIGS. 9 and 10 may be used. That is, in the kneading and extruding device 21 shown in FIGS. 4 and 5, since the die cone 62 is fixed by the spider 63 inside the die body 61, the molten material is diverted in the spider 63, and therefore, like the friction material material, When a large amount of the fiber component is contained, poor fusion or poor orientation of the fiber is likely to occur at the merging portion, and a molded article that is uniform in the circumferential direction may not be obtained. In this regard, the die head 6 shown in FIGS.
In the kneading and extruding device 21 provided with the OA, the screw 64A having a shape corresponding to the inner peripheral surface of the die pushing 65A and the die body 61A without the spider are used, so that the above-described poor fusion or fiber A molded article which is uniform in the circumferential direction without causing poor orientation can be always obtained.

[0046]

EXAMPLES Example 1 As an example, a donut plate-shaped friction plate was manufactured by the manufacturing method described in the embodiment of the present invention. Such a manufacturing method is hereinafter referred to as the present invention manufacturing method A.

Comparative Example As a comparative example, a donut plate-shaped friction plate was manufactured by the conventional manufacturing method shown in FIG. Such a manufacturing method is hereinafter referred to as a comparative manufacturing method X. [Experiment 1] According to each of the above-mentioned production method A of the present invention and comparative production method X, 1000 friction plates were continuously produced at one time, and this was performed 10 times, and the quality of the produced friction plates was evaluated. Table 1 shows the results. still,
The conditions of the friction plate to be manufactured in this experiment are as follows.

Outer diameter d1 of friction plate: 96.8 mm Inner diameter d2 of friction plate: 85.3 mm Difference between inner and outer diameters of friction plate: 11.5 mm Thickness t of friction plate: 1.6 mm

[Table 1]

As is evident from Table 1, it is recognized that the production method A of the present invention has less occurrence of defective products than the comparative production method X. This corresponds to the production method A of the present invention.
Then, there is no need to measure the friction material one by one,
This is because the occurrence of defective products due to the difficulty of weighing and the resulting variance in weighing is eliminated.

The number of sheets produced per hour was 3125 in the case of the production method A of the present invention and 400 in the case of the comparative production method X. The production number of the production method A of the present invention is determined as follows. That is, since the length of the molded body extruded per hour is 5 m and the thickness of the friction plate is 1.6 mm, the number of sheets produced per hour is 3125. According to the experimental results, it is recognized that the productivity of the manufacturing method A of the present invention is much higher than that of the comparative manufacturing method X.

Further, the friction material used in the production of the 10,000 total friction plates shown in Table 1 was prepared according to the production method A of the present invention.
Was 48 kg in Comparative Production Method X and 125 kg in Comparative Production Method X. Thereby, it is recognized that the material yield has been dramatically improved.

[Experiment 2] The stability of the quality of each friction plate manufactured in Experiment 1 was examined. The results are shown in FIGS. 11 (a) and 11 (b). Specifically, ten pieces are randomly selected from each of the first to tenth pieces of the 1000 pieces of friction plates produced by each manufacturing method, and each of the friction plates is divided into 12 equal parts in the circumferential direction. And
The density of each divided part was obtained, and the maximum value, the minimum value, and the average value were plotted in a graph. FIG. 11A shows the method A of the present invention, and FIG. Things.

From FIGS. 11 (a) and 11 (b),
In the case of the comparative manufacturing method X, the average value appears to be stable when viewed at each manufacturing time, but the maximum value and the minimum value are large, and it cannot be said that the average value is stable. However, in the case of the production method A of the present invention, the maximum value and the minimum value are very small, and it can be said that the method is stable. Here, the density is taken as a substitute property relating to the quality, but if the density is stable, it can be considered that other properties are also stable. Therefore, in the case of the production method A of the present invention, it can be said that the quality is very stable.

Example 2 The moldability, slicing characteristics, and friction characteristics of the extruded pipe-shaped molded body were examined while changing the content of the unvulcanized rubber with respect to the friction material raw material. Shown in

[Table 2]

The method of manufacturing the friction plate is the same as that of the above-described embodiment except that the content of the unvulcanized rubber with respect to the raw material of the friction material is changed. Here, the moldability was determined based on whether or not the extruded pipe-shaped molded product was good as a molded product. The slice characteristics are
The determination was made based on whether or not the pipe-shaped molded body was easily cut. The friction characteristics were determined based on the magnitude of the friction coefficient on the surface of the friction plate. However, the magnitude of the friction coefficient was determined within the range of the allowable friction coefficient (0.45 to 0.55) for the friction plate used for the clutch of the car air conditioner. Incidentally, for reference, if the maximum value (0.55) of the allowable friction coefficient is exceeded, the friction coefficient is too large and the normal function of the product incorporating the friction plate is impaired.

The conditions of the experiment are as follows.

Number of friction plates formed as experimental samples:
1000 pieces Condition of the above-mentioned friction plate Outer diameter d1: 96.8 mm of friction plate Inside diameter d2 of the friction plate: 85.3 mm Difference in inner and outer diameter of the friction plate: 11.5 mm Thickness of the friction plate t: 1.6 mm From the above Table 2, Unvulcanized rubber content is 10-30% by weight
It can be understood that there is no particular problem in the formability, slicing characteristics and friction characteristics of the pipe-shaped molded article within the range of the above. Further, it is recognized that when the content of the unvulcanized rubber is 20% by weight, optimum moldability, slice characteristics and friction characteristics can be obtained.

[0058]

As described above, according to the present invention, the following effects can be obtained.

(1) Rather than preforming and main forming one by one by a compression molding press as in the prior art, the material is continuously formed by a kneading extruder, so that the friction material material is measured one by one. This eliminates the need to perform the measurement, and can solve the problems associated with the measurement (difficulty and variation in the measurement) at a stretch, so that a donut-shaped friction plate having stable quality can be obtained.

(2) Further, in the prior art, an oversized friction plate material is made, and the material is formed into a friction plate having a small difference between the inner and outer diameters, which has to be finished to a predetermined size by machining or other methods. On the other hand, according to the method of the present invention, the inner and outer diameters can be easily formed into predetermined dimensions, so that finishing of the inner and outer diameters becomes unnecessary. Furthermore, the pipe-shaped molded article according to the present invention can easily perform ideal slicing processing with little cutting margin loss, the cut surface is in a state sufficient as the functional surface of the friction plate, and no thickness processing is performed. Can be provided for use. Accordingly, the amount of machining waste can be reduced to almost zero, and it is possible to contribute to preventing waste of the friction material.

(3) Further, according to the present invention, the number of elements in the manufacturing process can be greatly reduced as compared with the conventional method, the troublesome process management and the cost required for the process can be reduced, and a more inexpensive friction plate can be provided.

(4) The friction plate according to the present invention has a more excellent friction characteristic because the unvulcanized rubber is useful for improving the performance as a friction material in addition to the effect as a binder by the kneading action during extrusion molding. ing.

[Brief description of the drawings]

FIG. 1 is a manufacturing process diagram of a donut plate-shaped friction plate according to the present embodiment.

FIG. 2 is a perspective view of a pipe-shaped molded body.

FIG. 3 is a simplified cross-sectional view of an apparatus used in a manufacturing process of a pipe-shaped molded body.

FIG. 4 is a sectional view of the vicinity of a tip end of the kneading and extruding device.

FIG. 5 is a sectional view taken along line AA of FIG. 4;

FIG. 6 is a perspective view of a slice processing apparatus used in a manufacturing process of a third step n3.

FIG. 7 is a perspective view of a friction plate obtained by cutting a pipe-shaped molded body.

FIG. 8 is a cross-sectional view of a friction plate obtained by cutting a pipe-shaped formed body.

FIG. 9 is a cross-sectional view of the vicinity of a tip end of a kneading and extruding device provided with another die head 60A.

10 is a sectional view taken along the line AA in FIG. 9;

FIG. 11 is a graph showing a circumferential density distribution of each of a friction plate obtained by the method of the present invention and a friction plate obtained by the conventional method.

FIG. 12 is a manufacturing process diagram of a conventional donut plate-shaped friction plate.

[Explanation of symbols]

Reference Signs List 10: Pipe-shaped molded body 21: Kneading and extruding device 21a: Hopper 22: Storage tank 23: Feeder 24: Communication pipe 25: Continuous spiral body 30: First stirring means 31: Level sensor 32: Second stirring means 50: Donut shaped plate obtained by slicing

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3J056 AA57 BE09 FA02 FA08 GA11 3J058 BA61 BA63 BA73 GA61 GA62 GA64 GA65 GA92 GA93 4F207 AA36 AA45 AB25 AC01 AC04 AG08 AG19 AH12 AL08 AL16 AL17 AP14 AR15 KA01 KA17 KM33 KW23 KWK13

Claims (4)

[Claims] 1. A fiber component, a powdery filler component, a thermosetting resin component, and an unvulcanized rubber are stirred and mixed, and the mixture is melt-kneaded using a kneading apparatus to form a pellet-shaped or A first step of producing a granular friction material, a second step of supplying the pellet or granular friction material to a kneading and extruding apparatus, and continuously producing a pipe-shaped molded body by extrusion. A third step of sequentially cutting the pipe-shaped formed body at a predetermined thickness dimension pitch at right angles to the longitudinal direction to form a donut plate shape; and heat-treating the cut donut-shaped formed body, A fourth step of curing an uncured thermosetting resin component contained in the shaped body and simultaneously vulcanizing a rubber component, the method comprising the steps of: 2. A fiber component, a powdery filler component, a thermosetting resin component, and an unvulcanized rubber are agitated and mixed, and the mixture is melt-kneaded using a kneading device to form a pellet or pellet having a predetermined size. A first step of preparing a granular friction material, and a storage tank for storing the pellet or granular friction material, wherein the storage tank stores the pellet or friction material. (1) a storage tank provided with stirring means, a supply unit for sequentially dropping and supplying a predetermined amount of pellet-shaped or granular friction material to a hopper of a kneading and extruding apparatus, and a supply amount of the friction material raw material from the storage tank. A storage unit that includes a sensor for detection and a second stirring unit that stirs the friction material material, and supplies the friction material material supplied from the storage tank to the supply unit while stirring the friction material material by the second stirring unit. Feeder, A continuous spiral having one end communicating with the storage tank and the other end communicating with the storage part of the feeder, the spiral extending in the pipe axis direction and driven in response to the output of the sensor; And a connecting pipe in which a state body is disposed. Kneading the pellet-shaped or granular friction material raw material stored in the storage tank by a predetermined amount via the feeder without clogging. A second feeder is supplied to a hopper of an extruder and continuously produces a pipe-shaped molded body by extrusion.
Step, the pipe-shaped molded body, a third step of sequentially cutting at right angles in the longitudinal direction at a predetermined thickness dimension pitch to form a donut plate shape, and heat-treating the molded body cut into the donut plate shape, A fourth step of curing an uncured thermosetting resin component contained in the donut plate-shaped molded product and vulcanizing the rubber component at the same time, comprising: a fourth step of producing a donut plate-shaped friction plate. 3. The method according to claim 1, wherein the mixing amount of the unvulcanized rubber in the first step is 10 to 30% by weight based on the whole raw material of the friction material. A method for producing a donut plate-shaped friction plate. 4. An adhesive is applied to one of both side surfaces of a donut plate-shaped friction plate manufactured by the manufacturing method according to claim 1, and the adhesive is applied. A donut plate-shaped friction plate, which is dried to a touch-dry state.