JP2003120824A - Seal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a seal capable of being effectively used in a rolling bearing, a hub unit for an automobile, a linear guide device, a rolling device such as a ball screw, and having high slide contact characteristic to a seal contact face of a lip part. SOLUTION: The lip part 13 (the whole elastic body 3) composed of a rubber molding, of the seal 1 is made out of a rubber composition including hydrogenated acrylonitrile butadiene rubber having a carboxyl group as raw rubber.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolling bearing, an automatic
Car hub unit, automotive water pump, linear
Suitable for rolling devices such as guide devices and ball screws
About the rule. In particular, harsh water and dust
For rolling equipment used for grease lubrication in the environment
And a suitable seal. [0002] Conventionally, rolling elements have been provided on rolling bearings.
Grease and dust generated during use
Dust that leaks to the outside or floats outside is installed on rolling elements
Between the outer and inner rings to prevent
A seal may be installed between them. Such a system
FIG. 1 shows an example of a rolling bearing with a ball. [0003] The rolling bearing in this figure has seals on both sides.
The seal 1 has a hook on the outer periphery.
Ring-shaped cored bar 2 with synthetic rubber outside
And an elastic body 3 formed by vulcanization. this
Due to its function, the seal is located outside the hook of the core bar and outside.
Annular main part 11 made of an elastic body of
It is made of an elastic body on the outside and is formed in a stop groove 41 on the inner surface of the outer ring 4.
The crimping portion 12 to be locked and the elastic body on the inner peripheral side of the cored bar are used.
Sliding contact (sliding contact) with the receiving groove 51 on the outer peripheral surface of the inner ring 5
And a lip portion 13. The seal 1 has a lip 13
The crimping portion 1 is kept in contact with the receiving groove 51 on the outer peripheral surface of the inner ring.
2 is pressed against the stop groove 41 on the inner peripheral surface of the outer ring while being elastically deformed.
Between the outer ring 4 and the inner ring 5 of the rolling bearing.
It is arranged in. Also, as shown in FIG.
A seal 10 is also attached to the outer periphery of the unit 6.
The seal 10 is also made of a molded body of the core metal 20 and the rubber material.
And the elastic body 30. This hub unit
Numeral 6 shows a hub 61 and a flange 62 for receiving the shaft.
It is formed in. And this seal 10
Two lip portions 31 and 32 slidingly contacting the hub 61;
It has one lip portion 33 that slides on the flange 62. [0005] A common material for such a seal is a metal core.
Steel plates such as SPCC and SECC
Nitrile rubber, acrylic rubber,
Synthetic rubber such as silicon rubber or fluorine rubber is used
You. Water used in water-cooled engines of automobiles
ー Water enters the bearings supporting the rotating shaft into the pump
Seals to prevent grease leakage inside the bearing
Is attached. In this water pump, for example
For example, as shown in FIG. 4, an impeller 71 is fixed to one end.
The central part of the rotation axis S is spaced apart in the axial direction.
Several bearings J (in FIG. 4, a plurality of bearings are cut off).
The outer peripheral surface of the integrally formed outer ring is displayed instead of the surface.
ing. ) To the casing 72 so as to be rotatable.
It is attached. Cooling water W is supplied to the casing 72.
The cooling water container 73 to be put in is fixed. A seal is provided between the bearing J and the impeller 71.
By closing with 100, the cooling water evaporates with cooling water or heat
The generated steam is less likely to enter the bearing. [0007] However, the rolling
Bad environment in which the usage environment of the bearing is a large amount of moisture and dust
Environment, or the normal use environment is
The automotive hub unit is
The elasticity of the lip of the seal may decrease,
Of the lip seal contact surface
(The surface of the mating member that contacts the lip of the seal)
The sliding contact force (the force of sliding contact) decreases and the lip
When a small gap is created between the
Moisture and dust will enter the bearing. The result
As a result, the grease may deteriorate and the life of the bearing may be shortened.
You. Further, the present applicant has previously disclosed a water heater for an automobile.
-Hydrogenated nitrile rubber (HNB)
R) was proposed to use a seal consisting of
No. 11-193795). According to this proposal,
Even if the operating environment temperature is 110 ° C or higher, the lip
Good sliding contact with the metal contact surface (sealing performance)
A cheaper seal is provided, but this seal has
There is room for good. [0009] The present invention relates to a rolling bearing and a hub unit for an automobile.
Kit, automotive water pump, linear guide device,
A high temperature lid suitable for rolling devices such as ball screws
The sliding contact with the seal contact surface of the
An object of the present invention is to provide a more excellent seal. [0010] To solve the above problems,
According to the present invention, the rubber molded body forming the lip portion is a raw rubber.
Acrylonitrile buta having carboxyl group
Diene rubber (hereinafter referred to as “carboxylated HNBR”)
You. A) a seal made of vulcanized rubber
I will provide a. In the present invention, carbohydrate is used as a raw material rubber.
By using xylated HNBR, it can be used as raw rubber.
Vulcanized rubber obtained than using HNBR
(Lip part of the seal)
And excellent flex fatigue resistance. For example, raw rubber
Vulcanized rubber using carboxylated HNBR as
Means that the tensile strength at which the elongation at break is 200% is 20M
Vulcanized rubber using ordinary NBR
The strength is 15 to 19 MPa. Accordingly
Thus, according to the seal of the present invention, the seal contact surface of the lip portion
Sliding force against the seal is higher than the seal described in the above publication.
You. Carboxylated HNBR used in the present invention
Carboxylic acid group and carboxylic acid anhydride
And the peak height of both groups obtained by infrared absorption spectrometry
([Peak height of carboxylic anhydride group] /
｛[Peak height of carboxylic anhydride group] + [carboxyl
Group peak height]｝) is 0.5 or more and the acid equivalent is 1
× 10 ^-Four It is preferably at least ephr. The acid equivalent is a value measured by the following method.
You. First, the rubber is dissolved in acetone and n-hexane
After reprecipitation purification, the purified rubber was redissolved in pyridine
To obtain a rubber solution. Next, in this rubber solution
Thymolphthalein is added as an indicator and the solution is concentrated.
Apply 0.02N potassium hydroxide ethanol solution
Add dropwise until the color of the indicator changes. Next, this Ethanor
Calculate the acid equivalent to 100 g of rubber from the drop amount of
Put out. When the ratio is less than 0.5, scorch (addition)
Initial vulcanization occurs during processing before the vulcanization process,
Processing becomes impossible) and
The abrasion is reduced, and the compression set tends to increase. Ma
The acid equivalent is 1 × 10 ^-Four If less than ephr, pull
Strength and abrasion resistance decrease. Seat for rolling device of the present invention
In JIS, the hardness of the lip is determined according to “JIS K630
Spring hardness A scale described in 1), 50 to 90
Is preferably within the range. As a result, the seal
The sealing performance by the top portion is improved. If the hardness of the lip is less than 50,
When the lip rotates, the lip deforms more than necessary,
The heat generation and the torque rise are likely to occur in the pump portion. As a result,
Frictional resistance during operation of the
Rolling movement may be difficult. More than 90
And the rubber elasticity decreases, causing the seal contact surface of the lip to
Sliding contact force is insufficient, and sufficient sealing performance cannot be obtained.
You. Particularly preferred hardness of the lip is spring hardness A
It ranges from 70 to 80 on a scale. The rubber composition used in the present invention is a raw rubber.
And a vulcanizing agent as essential components.
Agents, vulcanization accelerators, antioxidants, reinforcing agents, plasticizers,
Compounding agents such as a pulling agent may be appropriately compounded as necessary.
Can be. The rubber composition may also contain
Reinforcing filler, processing aid, wear improver, lubricating oil, lubricant
Etc. can be added. In addition, with respect to the rubber composition
To adjust the amount of reinforcing filler, wear modifier, etc.
Therefore, a rubber molded body having a predetermined hardness can be obtained. The raw rubber of the rubber composition used in the present invention is
Specific examples of the other components will be described below. Vulcanizing agent
(Crosslinking agent) as powdered sulfur, sulfur flower, precipitated sulfur,
Various sulfur such as highly dispersible sulfur, morpholine disulfide
, Alkylphenol disulfide, N, N-dithio
-Bis (hexahydro-2H-azepinone-2) -thiu
Sulfur compounds that can release sulfur such as ram polysulfide
Substance, dicumyl peroxide di (t-butyl peroxy)
C) diisopropylbenzene, 2,5-dimethylhexa
And peroxides such as benzoyl peroxide.
It is. Of these, dispersibility, ease of handling, and
In terms of heat resistance, highly dispersible sulfur and morpholine disulfide
It is preferred to use As a vulcanization accelerator, a sulfur-based vulcanizing agent is used.
If present, guanidine-based, aldehyde-ammonia
Series, thiazole series, sulfenamide series, thiourea series,
Thiuram, dithiocarbamate, xanthate, etc.
Must be used. A small amount of highly dispersible sulfur
Thiuram tetramethylthiuram disulfur
N-cyclobenzyl-
2-benzothiazyl or sulfenamide and thiazo
In combination with 2-mercaptobenzothiazole
Preferably. Examples of the vulcanization accelerating aid include metals such as zinc oxide.
Oxides, metal carbonates, metal hydroxides, stearic acid, etc.
Fatty acids and their derivatives, amines, and the like.
When zinc oxide is used, scorched carboxylated HNBR
Zinc (early vulcanization) is likely to occur.
Preference is given to using mixtures of acid acids. Zinc peroxide
At the temperature at the time of kneading the rubber composition
Because it is present in the product and produces zinc oxide during vulcanization molding,
Premature vulcanization does not occur during kneading and storage. As antioxidants for preventing oxidative deterioration,
Amine-ketone condensation products, aromatic secondary amines,
Nophenol derivatives, bis or polyphenol derivatives,
Vidroquinone derivative, sulfur-based anti-aging agent, phosphorus-based anti-aging
And the like. Of these, amine-ketone condensation products
2,2,4-Trimethyl-1,2-dibidoki
Condensation of norline polymer or diphenylamine with acetone
N, N'-di- which is an aromatic secondary amine compound
β-naphthyl-p-phenylenediamine, 4,4'-bi
Su- (α, α-dimethylbenzyl) diphenylamine,
Or N-phenyl-N ′-(3-methacryloyloxy
-2-hydroxypropyl) -p-phenylenediamine
Are preferred. Further, heat decomposition is prevented to improve heat resistance.
Therefore, a secondary antioxidant is used together with the above antioxidant.
Is more preferable. As secondary anti-aging agents, sulfuric acid
Yellowish 2-mercaptobenzimidazole, 2-merca
Ptomethylbenzimidazole and their zinc salts
can give. In addition, the turtles
Melting point of 55 to 7
Wax at about 0 ° C to 100 parts by weight of raw rubber
About 0.5 to 2.0 parts by weight. 0.5 weight
If it is less than the amount, cracks due to the action of ozone are prevented.
No effect is obtained, and if it exceeds 2 parts by weight, it is unnecessary
Processability due to the exudation of wax on the rubber surface
Problem. When it is necessary to further improve the formability
, A plasticizer is appropriately added as a processing aid. Formability
If there is no problem, there is no need to add a processing aid.
When added, the amount added is based on 100 parts by weight of the raw rubber.
3 to 20 parts by weight. If added more than necessary, rubber
As the composition softens, bleed without complete mixing
Out may occur. Specific examples of the plasticizer include dioctyl lid
Phthalic acid diester such as acrylate, adipate plasticizer,
Sebacate plasticizer, phosphate plasticizer, polyate
Ter plasticizer, polyester plasticizer, polyether ether
Examples include a stell plasticizer and a liquid rubber. Recent environment
Considering hormonal issues, adipate plasticizer
Kate plasticizer, phosphate plasticizer, polyether
Plasticizer, polyester plasticizer, polyether ester
It is more preferable to use plasticizer, liquid rubber, etc.
No. As the coupling agent, silane-based,
Minium-based, titanate-based coupling agents, for example,
γ-mercaptopropyltrimethoxysilane, γ-gly
Sidoxypropyltrimethoxysilane, γ-methacrylo
Xypropyltrimethoxysilane and the like. Reinforcement
Carbon black and white fillers
No. Specifically, as carbon black, I
SAF (Intermediate Super Abrasion Furnace black)
, MAF (Medium Abrasion Furnace black), SRF
(Simi-Reinforcing Furnace black), GPF (General
Purpose Furnace black), FT (Fine Thermal Furnac
e black), MT (Medium Thermal Furnace black), HA
F (High Abrasion Furnace black), FEF (Fast Extr
uding Furnace black). this
Of these, HAF and FEF are preferred because of their high reinforcing properties.
No. Examples of the white filler include various silicas and bases.
Magnesium carbonate, activated calcium carbonate, special carbonic acid
Calcium, super differential magnesium silicate, clay, tal
Diatomaceous earth, wollastonite and the like. Carb
Use reinforcing fillers that mix black and white fillers
It may be. Use rubber composition with reinforcing filler
In this case, the wear resistance of the lip portion is increased. As a result,
The sealing performance is improved by the lip of the tool. Reinforcing filling
In the case of carbon black, the additive amount of the raw material rubber 10
20 to 90 parts by weight with respect to 0 parts by weight. 20 parts by weight
If it is less than 30, sufficient reinforcing properties are not exhibited, and 90
If the amount exceeds the parts, the hardness of the rubber composition increases and
The elongation decreases, and the inherent rubber elasticity decreases. In the case of a white reinforcing agent, addition of a reinforcing filler
The amount is 20 to 150 parts by weight based on 100 parts by weight of the raw rubber.
And The amount of the reinforcing filler added is less than 20 parts by weight
Does not exhibit sufficient reinforcing properties and exceeds 150 parts by weight
And, the hardness of the rubber composition increases and the elongation rate decreases.
And the inherent rubber elasticity decreases. With reinforcing filler
Using a mixture of carbon black and a white reinforcing agent
If 100% by weight of raw rubber is used,
10 to 90 parts by weight of rack, 10 to 110 weight of white reinforcing agent
Within the range of parts by weight, the total content becomes 20 to 200 parts by weight.
To do. The total content of the reinforcing filler is not more than 20 parts by weight.
If it is full, sufficient reinforcing properties are not exhibited, and 200 parts by weight
If it exceeds, the hardness of the rubber composition increases and the elongation percentage increases.
, And the inherent rubber elasticity decreases. As the wear improver, polyolefin particles
And spherical carbon fine particles. Polyolefin particles
Specifically, polyethylene, polypropylene
Particles, preferably carboxyl-modified polyethylene
(Maleic anhydride-modified polyethylene), carboxyl-modified
Polypropylene (maleic anhydride-modified polypropylene)
Particles). Polyethylene and polypropylene are
When voxil-modified, carboxyl groups in the structure
And easily adsorb to various rubbers and oxides. Also, raw materials
Carboxyl groups present in rubber also exert a similar effect
Because of these synergistic effects, tensile strength and wear resistance
It is thought that mechanical strength such as resistance and bending fatigue resistance will be further improved
Can be The amount of polyolefin particles added depends on the rubber composition.
The raw rubber 1 is selected from the balance between the wear resistance of the material and other physical properties.
It is preferable to use 10 to 60 parts by weight for 00 parts by weight.
No. When the amount is less than 10 parts by weight, the effect of improving abrasion resistance is improved.
Fruit is low. Conversely, if it exceeds 60 parts by weight, the hardness of the rubber composition
Increases, elongation decreases, and rubber elasticity decreases.
You. As lubricating oils, ether oils, silicone oils
Corn oil, poly-α-olefin oil, fluorine
And fluorinated surfactants. Among them
Silicone oils are more preferred, and
Modified silicone oils are particularly preferred. This sensuality
The group reacts with the main chain of the rubber, and the oil
Prevent oozing at once, and gradually and permanently
It is thought to come out. Lubricating oil is liquid
Easily exudes on the surface of the rubber composition
There is fruit. The amount of lubricating oil added is 100 parts by weight of raw rubber.
2 to 30 parts by weight with respect to As a result, the rubber composition
The lubricity of objects is improved. Less than 2 parts by weight of lubricating oil
, Sufficient lubricity is not exhibited and exceeds 30 parts by weight.
In addition, poor dispersion of additives may occur during rubber processing.
Not good. Hereinafter, embodiments of the present invention will be described.
explain. Nos. 1 to 11 of the compositions shown in Table 1 below and Table 2
Rubber compositions Nos. 12 to 19 having the compositions shown in Table 1 were prepared. [Table 1] [Table 2] The materials in Tables 1 and 2 are as follows.
You. ☆ Rubber A: Middle and high nitrile NBR (manufactured by JSR Corporation)
"N230S") ☆ Rubber B: Carboxylated HNBR (Zeon Corporation)
Rubber Co., Ltd. ☆ Raw material C: Carbogisylated NBR (Nippon Zeon Co., Ltd.)
"Nipol DN631" manufactured by the company) ☆ Rubber D: hydrogenated NBR (manufactured by Zeon Corporation)
"Zetpol 2020") ☆ Rubber E: Fluorine rubber (manufactured by Daikin Industries, Ltd.)
"Daiel G-801") ☆ Rubber F: Hydrogenated carbogysylated NBR (Bayer
"Telvan XT" manufactured by Le Co., Ltd. ☆ Carbon black A: HAF (Mitsubishi Chemical Corporation)
"Diablack H") ☆ Carbon Black B: MT (Cancarb's "Th
ermax N990 ") ☆ Carbon Black C: SRF (Tokai Carbon Co., Ltd.)
"SEIST S") ☆ Clay: Fired clay (Tsuchiya Kaolin "SATINT"
ONE No. 5 ") ☆ Silica: hydrous silica (Nippon Silica Industry Co., Ltd.
Vulcanizer: Highly dispersible sulfur (Tsurumi Chemical Co., Ltd. “Su”
lfalx PMC ”) ☆ Vulcanization accelerator A: Tetramethylthiuram disulfide
(“Axel TMT” manufactured by Kawaguchi Chemical Co., Ltd.) ☆ Vulcanization accelerator B: Tetraethylthiuram disulfide
(“Noxeller TET” manufactured by Ouchi Shinko Chemical Co., Ltd.) ☆ Vulcanization accelerator C: N-cyclohexyl-2-benzothia
Jill Sulfenamide (Kawaro Chemical Industries, Ltd.
Xcel CZ-R ") ☆ Vulcanization accelerator A (also used as lubricant): stearic acid (flower)
"Lunac S-35" manufactured by Oo Corporation) Vulcanization Accelerator B: Zinc oxide (Sakura Chemical Co., Ltd.
No. 1) ☆ Vulcanization accelerator A: Zinc oxide (manufactured by Zeon Corporation)
"ZeonetZP"), added by masterbatch method ☆ Activator: Organic amine ("Actin" manufactured by Yoshitomi Pharmaceutical Co., Ltd.
SL)) ☆ Plasticizer: adipic acid-based polyester (Asahi Denka Co., Ltd.)
"PN-350") ☆ Abrasion modifier: carboxyl-modified polyethylene particles
"Modic-AP H501" manufactured by Ryo Kagaku Co., Ltd.) ☆ Antiaging agent A: 4,4-bis- (α, α-dimethylbenz)
Ndyl) diphenylamine (Ouchi Shinko Chemical Co., Ltd.)
"Nocrack CD") ☆ Antiaging agent B: 2-mercaptobenzimidazole
(“Nocrack MB” manufactured by Ouchi Shinko Chemical Co., Ltd.) ☆ Antiaging agent C: Special wax (Ouchi Shinko Chemical Co., Ltd.
Lubricant: Amino-modified silicone oil (Shin-Etsu Silicon Co., Ltd.)
Co., Ltd. “KF-860”) ☆ Coupling agent: γ-mercaptopropyl trimethod
Silicone (“KBM803” manufactured by Shin-Etsu Silicone Co., Ltd.) Using the rubber compositions of Nos. 1 to 8,
Specimens for the length test and the tensile test were prepared. First, each of the components excluding the vulcanizing agent and the vulcanization accelerator was used.
Charge the ingredients into a Banbury mixer and mix at a mixer temperature of 80.
Kneading was carried out at 1 ° C. (first kneading step). Next, this kneaded
Remove the material from the Banbury mixer and
Into a rubber kneading roll machine. Next, roll temperature
While controlling the temperature to 50 ° C, the vulcanizing agent and
And vulcanization accelerator, and turn back until uniform.
After performing the operation (second kneading step), it was formed into a sheet. Next, a hot press machine heated to 170 ° C.
Then, a vulcanizing mold for a sheet having a thickness of 2 mm is attached to the mold.
The sheet obtained in the second kneading step was placed in a mold.
Then, heat and press for 15 minutes, length 150mm, width
A vulcanized rubber sheet having a thickness of 150 mm and a thickness of 2 mm was obtained. this
For punching a rubber sheet into the shape of a JIS No. 3 test piece
From the test specimens for tensile test and hardness test
Was. In the tensile test, this test piece was tested using a universal testing machine.
To the tensile test, tensile strength and
The elongation at break was measured. In the hardness test, three test pieces
Used repeatedly, based on “JIS K6301”
The hardness was measured using a ring hardness A scale. these
Are shown in Table 3 below. [Table 3] [First Embodiment] The rolling bearing shown in FIG.
Seal 1 was produced by the following method. SPCC core metal 2
And rubber compositions of Nos. 1 to 8, 12 to 19 for forming seals
By placing it in a vulcanizing mold of
A vulcanized molded body made of each rubber composition was used as an elastic body 3 as a core.
It was integrally molded outside the gold 2. The lip of the elastic body 3
The part 13 had the shape shown in FIG. Each of the obtained seals (the elastic body 3 is No. 1 to No. 1)
It is a vulcanized rubber comprising each of the rubber compositions of 8, 12 to 19.
Seal 1) is 6203 (call number) manufactured by NSK Ltd.
No.) Inner ring 5 and outer of single row deep groove ball bearing (rolling bearing in FIG. 1)
Assembled between wheels 4. This bearing is manufactured by Nippon Seiko Co., Ltd.
Apply grease: ether-based grease to the bearing rotation tester.
Leasing, ambient temperature: 120 ° C, rotation speed: 5000r
pm, rotation time: after rotating under the condition of 1000 hours
Next, the presence or absence of grease leakage and lip cut was examined. The results of these tests are shown in Table 4 below. The
In case of lease leakage and lip breakage
“×”, and the case where it did not occur was “○”. In addition, raw materials
Nos. 1 to 6, 12 in which the rubber is carboxylated HNBR
1 provided with an elastic body 3 made of a rubber composition
Are seals (Examples 1-1 to 1-1) within the scope of the present invention.
3). Raw rubber is other than carboxylated HNBR
An elastic body 3 made of a rubber composition of No. 7, 8, 19
The seal 1 provided was a seal outside the scope of the present invention (Comparative Example 1).
-1 to 1-3). [Table 4] As can be seen from the results in Table 4, Example 1
In bearings incorporating seals 1 to 1-13, the rotation
Tests also cause grease leakage and seal breakage
In contrast, the seals of Comparative Examples 1-1 to 1-3 were used.
For the installed bearings, grease leakage is
And seal breakage. [Second Embodiment] Seal 1 of hub unit 6 shown in FIG.
0 was produced by the following method. SPCC core metal 20 and N
o. The rubber composition of 1 to 8, 12 to 19 is used for forming a seal.
Each is placed in a vulcanizing mold and heated and pressed,
A vulcanized molded body made of the rubber composition was used as an elastic body 30 as a core.
It was molded integrally with the gold 20. The lip of the elastic body 30
31 to 33 have the shapes shown in FIG. Each of the obtained seals (the elastic body 30 is No. 1 to No. 1)
It is a vulcanized rubber comprising each of the rubber compositions of 8, 12 to 19.
3), each of which is shown in FIG.
Is attached to the hub unit 6 of which is 60 mm,
Attached to Nippon Seiko Co., Ltd. hub unit rotation tester
Was. Then, the muddy water is applied to the hub unit 6 and the seal 10.
Turn the hub unit under the following conditions while
I let you. Mud water supply condition: 2 liters of mud per minute for 10 seconds
After that, stop muddy water for 20 seconds.
Repeated encapsulation between hub unit 6 and seal 10
Grease: mineral oil grease, ambient temperature: room temperature, rotation speed
Degree: 1000 rpm, rotation time: 72 hours. After this rotation test, the sealed green of each specimen was
Measure the amount of water contained in the
Depending on the content relative to the lease mass, the lip of the seal 10
Sliding contact of the parts 31 to 33 with the hub unit 6 (sealing
Sex) was evaluated. If the content is 1.0% or less,
For the hub unit 6 of the lip portions 31 to 33 of the seal 10
Good sliding contact property is evaluated as "O" and 2.0 to 5.0%
Slightly bad "△", bad if more than 5.0%
“×” was assigned. Before and after this rotation test, the seal 10
Measure the shape, and from these measurement results,
The amount of wear of the seal 10 was calculated. The seal 10
Insert a thermocouple inside the lip (main lip) 32 of
And rotate the shaft with the shaft eccentricity set to 0.
(When rotated over) the temperature of the lip (main lip) 32
Was measured. The results are shown in Tables 5 to 7 below.
Table 5 shows that the elastic body 30 of the seal 10 is used as a reinforcing filler.
Rubber compositions containing carbon black (No. 1 to No. 1)
3, 7) are summarized. table
6, the elastic body 30 of the seal 10 is used as a reinforcing filler.
From rubber composition with silica added (Nos. 4 to 6, 8)
This is a summary of the results in the following cases. Table 7 shows the seal
The elastic body 30 of No. 10 was a rubber composition (No. 1) shown in Table 2.
2 to 19) are summarized. The raw rubber is carboxylated HNBR.
Consisting of rubber compositions of Nos. 1 to 6, 12 to 18
The seal 10 provided with the body 30 is a seal within the scope of the present invention.
(Examples 2-1 to 2-13). Raw rubber is cal
Nos. 7, 8, and 19 rubbers other than boxylated HNBR
The seal 10 provided with the elastic body 30 made of the composition
It is a seal (comparative examples 2-1 to 2-3) outside the range of light. Also, the ratio of the amount of wear in Tables 4 and 6
Is a value when the wear amount of Example 2-1 is “1”. table
The ratio of the wear amount in Example 5 is the same as the wear amount in Example 2-4.
The value is “1”. [Table 5] [Table 6] [Table 7] As can be seen from the results of Tables 5 to 7,
Bearings incorporating seals 2-1 to 2-13 are comparative examples.
Compared to bearings incorporating 2-1 to 2-3 seals,
For the hub unit of the lip part in the rotation test
Excellent sliding and abrasion resistance, high sealing performance
Was done. Further, the elastic body 30 of the seal 10 is a wear improver.
(Carboxyl-modified polyethylene particles)
2-2 consisting of a rubber composition (No. 2, 5, 13),
In 2-5 and 2-8, the wear resistance was particularly high. Further, the elastic body 30 of the seal 10 is lubricated.
Rubber composition with oil (silicone oil) (No.
Examples 2-3, 2-6, and (3, 6, 14)
2-9, the heat generation is suppressed due to the high lubricity of the elastic body 30
As a result, the temperature of the main lip is 45 ° C., 49 ° C., 44 ° C.
And especially low. [Third Embodiment] The seat of the water pump 7 shown in FIG.
Was manufactured by the following method. This water pon
FIG. 5 shows an enlarged view of the seal 100 of the step 7.
You. SPCC core metal 200 and rubber composition of Nos. 1 to 19
The product is placed in a vulcanizing mold for forming
By doing so, the vulcanized molded body composed of each rubber composition,
The elastic body 300 is formed integrally with the outside of the core bar 200.
Was. This elastic body 300 is used for cooling water container 73 side.
Two lip parts 301 and 302 facing and facing the bearing J side
It has one lip 303. Also this water
A slinger 8 is fitted on the rotation shaft S of the pump 7.
The seal 100 is configured such that the caulking portion 150 of the elastic body 300 is
By engaging the stop groove 410 provided on the inner surface of the
Installed. With this installation, the slinger
The lip (main lip) 30 is provided on the outer peripheral surface of the small cylindrical portion 81 of FIG.
1 comes into contact with the outer peripheral surface of the large cylindrical portion 82 of the slinger 8.
The lip (sub lip) 302 comes into contact with the lip 303
The state comes into contact with the rotation axis S. Each of the obtained seals (the elastic body 300 is No. 1
Seals which are vulcanized rubbers comprising the respective rubber compositions of Nos. 1 to 19)
100 is an axis supporting the rotation axis S of the water pump 7
Between the receiver J and the slinger 8 fitted to the rotating shaft S.
I attached. In this state, the bearing J and the rotating shaft S are shown in FIG.
The seal 100 is rotated in water.
A test was conducted. This test apparatus has one end (the impeller) of the rotating shaft S.
Drive pulley 91 for fixing the bearing 71) and a bearing.
A housing 92 into which the outer ring G of J is fitted and cooling water
93a and 93b for forming a space 93
For measuring the electrical resistance between the material 93a and the rotation axis S
Circuit 94 and heater for heating housing 92 from the outer periphery
95. The piping 96 for introducing the cooling water is connected to the member 9.
3b through the space 93 to the nearest position of the bearing J in the space 93.
It is installed in. This pipe 96 is connected via a metering pump.
Connected to cooling water supply. This allows testing equipment
A certain amount of cooling water is introduced into the space 93 of
ing. A thermocouple 97 for measuring the temperature of the outer ring G is provided.
It is installed in the housing 92. The bearing J has a length covering the entire large-diameter portion of the rotating shaft S.
Outer ring G made of a cylindrical body and a large-diameter portion seal 100 side
The inner ring groove N formed on the inner ring groove N and the groove of the outer ring G
Between the plurality of balls T arranged between the shaft and the large diameter portion of the rotation axis S.
Composed of a plurality of rollers X installed between the roller 91 side
Have been. This rotation test was performed using the heating temperature of the heater:
Perform under the conditions of 150 ° C. and rotation speed: 8000 rpm.
For every 00 hours of rotation, the main lip 30 of the seal 100
1. Hardness measurement and water content in grease in bearing
Was measured. The hardness measurement was performed by IRHD (Internationa
l Rubber Hardness Degree) Micro hardness point
By measuring the change in point hardness
Was used as an indicator of the increase in The measured water content (quality
Amount) based on the content of the
Is evaluated for sealing performance, when the content is 5.0% or more.
Was regarded as defective. In this rotation test, the seal is different
Prepare 100 test specimens for each test.
Then, the average value of 100 bodies was measured. The test results are shown in FIGS.
Indicated by The raw rubber is carboxylated HNBR.
No. 1-6 rubber composition or raw rubber is hydrogenated
Carbylated HNBR No. 12-18 rubber set
The seal 100 provided with the elastic body 300 made of
Seal within the scope of the invention (Examples 3-1 to 3-6, 3-7
３−3-13). Raw rubber is carboxylated HNB
R and hydrogenated carboxylated HNBR
Elastic body 3 made of rubber composition No. 7 to 11, 19
00 with a seal 100 outside the scope of the present invention.
(Comparative Examples 3-1 to 3-6). This example and ratio
The number of the comparative example and the type (No.) of the rubber composition used
The correspondence is shown in Table 8 below. [Table 8] FIG. 7 shows the relationship between the rotation time and the amount of increase in hardness.
It is a graph shown. Fig. 8 shows the rotation time and the rate of defective sealing performance.
6 is a graph showing a relationship with the graph. From these results
As described above, the seals of Examples 3-1 to 3-13 were incorporated.
The bearing was a shaft incorporating the seals of Comparative Examples 3-1 to 3-6.
700 hours in water at 150 ° C compared to
The amount of increase in hardness is extremely small even when rotating for 900 hours.
Even after rotation, the degree of deterioration of the sealing performance was extremely low. This
As a result, the embodiment is
The seals of 3-1 to 3-13 are the same as those of Comparative Example 3-4.
Seal made of toril rubber (HNBR)
No. 10 seal containing rubber composition)
It is also found that the sealing performance is maintained for a long time
Was. In this embodiment, for a rolling bearing,
For hub unit and water pump seals
Although the seal of the present invention is described,
Rolling device (for example, linear guide device, ball screw, etc.)
It is also suitable for use. FIG. 9 shows a linear guide device.
You. As shown in FIG. 9A, the linear guide device
The rail 5 includes a rail 510 and a slider 520.
20 are provided with seals 110 at both ends in the sliding direction.
ing. This seal 110 is, as shown in FIG.
From the metal core 210 and the rubber elastic body 310
And has three lip portions 311 to 313. FIG. 10 shows a ball screw. FIG. 10 (a)
As shown in the figure, the ball screw is composed of the screw shaft 610 and the nut 62.
And seals 12 at both ends in the axial direction of the nut 620.
0 is attached. This seal 120 is shown in FIG.
As shown in (b), a metal core 220 and a rubber bullet
Consisting of the sexual body 320 and the screw groove 611 of the screw shaft 610
It has a lip 321 to be in contact. As described above, according to the present invention,
Used as the raw rubber for the rubber composition that forms the lip of the seal
By using carboxylated HNBR,
Bearings, automotive hub units, automotive water pumps
For rolling devices such as pumps, linear guide devices, ball screws, etc.
To the seal contact surface of the lip at high temperature
A seal with high sliding properties can be obtained. That is, this seal is used to seal the lip.
Water and dust
High sealing even in harsh environments where there are many
Grease leakage and moisture and dust penetration
Is prevented. Therefore, the seal of the present invention may be
Used in harsh environments where there is a large amount of
Equipment (rolling bearings, automotive hub units, automotive
Water pump, linear guide device, ball screw, etc.)
Installation extends the life of this rolling device.
Can be

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view showing an example of a rolling bearing with a seal. FIG. 2 is a cross-sectional view showing a shape of a lip portion of the rolling bearing seal manufactured in the first embodiment. FIG. 3 is a sectional view showing an example of a hub unit with a seal. FIG. 4 is a sectional view showing an example of a water pump. FIG. 5 is a sectional view showing a shape of a bearing seal of a water pump manufactured in a third embodiment. FIG. 6 is a sectional view showing a test device used in a third embodiment. FIG. 7 is a graph summarizing test results of the third embodiment and showing the relationship between rotation time and hardness increase. FIG. 8 is a graph summarizing the test results of the third embodiment and showing the relationship between the rotation time and the sealing performance failure rate. 9A is a perspective view illustrating a linear guide device, and FIG. 9B is a cross-sectional view illustrating a seal of the linear guide device. FIG. 10A is a front view illustrating a ball screw, and FIG. 10B is a cross-sectional view illustrating a seal of the ball screw. [Description of Signs] 1 seal 11 main part 12 caulking part 13 lip part 2 core metal 3 elastic body 4 outer ring 40 outer ring 41 stop groove 410 stop groove 5 inner ring 51 receiving groove 6 hub unit 61 hub 62 flange 7 water pump 71 impeller 72 Casing 73 Cooling water container 10 Seal 20 Metal core 30 Elastic body 31 Lip part 32 Lip part (main lip) 33 Lip part 8 Slinger 81 Small cylindrical part of slinger 82 Large cylindrical part of slinger 91 Drive pulley 92 Housing 93 Cooling water Forming space 93a Forming member 93b for space for cooling water Forming member 93 for space for cooling water Electrical resistance measurement circuit 95 Heater 96 Piping for introducing cooling water 97 Thermocouple 100 Seal 110 Seal 120 Seal 150 Seal 150 Caulking part 200 Core metal 210 core metal 220 core metal 300 elastic body 301 lip (main lip) 302 Lip part (sub lip) 303 Lip part 310 Elastic body 311 Lip part 312 Lip part 313 Lip part 320 Elastic body 321 Lip part 510 Guide rail 520 Slider 610 Screw shaft 611 Screw groove 620 Nut J Bearing N Inner ring groove G Outer ring S Rotation Shaft T Ball X Roller W Cooling water

   ────────────────────────────────────────────────── ─── Continuation of front page    (72) Inventor Takahiko Uchiyama             Kanagawa Prefecture Fujisawa City Kugenuma Shinmei 1-chome 5-50             Nippon Seiko Co., Ltd. F-term (reference) 3J006 CA01                 3J016 AA01 BB03                 4H017 AA03 AA27 AA29 AB01 AC14                       AC16 AD06 AE05                 4J002 AC101 AC111 FD019 FD028                       FD146 FD157 GM00

Claims (1)

Claims: 1. A seal characterized in that a rubber molded body forming a lip portion is made of a vulcanized rubber whose raw rubber is hydrogenated acrylonitrile butadiene rubber having a carboxyl group.