CN1327179A - Bearing device for roller support - Google Patents

Bearing device for roller support Download PDF

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Publication number
CN1327179A
CN1327179A CN01121331A CN01121331A CN1327179A CN 1327179 A CN1327179 A CN 1327179A CN 01121331 A CN01121331 A CN 01121331A CN 01121331 A CN01121331 A CN 01121331A CN 1327179 A CN1327179 A CN 1327179A
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CN
China
Prior art keywords
bearing
lip seal
roller support
lip
pressed
Prior art date
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Granted
Application number
CN01121331A
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Chinese (zh)
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CN1196980C (en
Inventor
藤本隆
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NTN Corp
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NTN Corp
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Publication of CN1327179A publication Critical patent/CN1327179A/en
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Publication of CN1196980C publication Critical patent/CN1196980C/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
    • F16C33/72—Sealings
    • F16C33/74—Sealings of sliding-contact bearings
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C17/00—Sliding-contact bearings for exclusively rotary movement
    • F16C17/02—Sliding-contact bearings for exclusively rotary movement for radial load only

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Sealing With Elastic Sealing Lips (AREA)
  • Sealing Of Bearings (AREA)
  • Dry Development In Electrophotography (AREA)
  • Rolls And Other Rotary Bodies (AREA)

Abstract

The present invention provides a roller supporting bearing device to prevent the problem such as fluctuation of the turning torque of a roller and wearing of bearing, and to dispense with highly accurate part management. In this roller supporting bearing device having a bearing and a lip packing for protecting the interior of the bearing, the lip packing is formed by an integral molding article of an elastic body, and the integral molding article is formed by a lip part brought into sliding contact with the peripheral surface of a support shaft supported on the bearing and a fixed part fixed to the bearing. The fixing part is fitted to the bearing by press-in.

Description

Bearing device for roller support
The present invention relates to bearing device for roller support, particularly about the bearing device for roller support of the display of electro-photography apparatus such as duplicating machine, laser printer.
In general, the display of electro-photography apparatus such as duplicating machine, laser printer by stirring the developer of colorant, toner, carrier etc., is transplanted on this developer on the photosensitive drum surface, and this surperficial electrostatic latent image is adhered to developer, carries out video picture.
The structure of such display is described below by Fig. 8 and Fig. 9.Fig. 8 is the skeleton diagram of display, and Fig. 9 is the enlarged drawing of the B portion of Fig. 8.
Display is equipped with a plurality of agitating roller 8a, 8b, and these agitating rollers 8a, 8b stir developer 7 in the video picture groove 6 that constitutes shell, be equipped with kinescope 8c in the position of docking with photosensitive drums 9.
Be arranged on the back shaft 4 on the shaft end of each roller 8a, 8b, 8c, supporting free to rotately,, be provided with rotary driving part 11 from the outstanding shaft end of cell wall by the bearing arrangement on the cell wall that is installed on video picture groove 6 10.
In addition, in order to prevent that developers 7 in the video picture groove 6 from invading the inside of bearing arrangements 10 and to the leakage of video picture groove 6 outsides, bearing arrangement 10 is made of bearing 13 and lip seal 12.Fig. 5～Fig. 7 shows the sectional drawing of bearing arrangement 10 in the past.Fig. 5 is the sectional drawing of bearing arrangement 10, and Fig. 6 is the sectional drawing of lip seal 12, and Fig. 7 is the sectional drawing of bearing 13.
Bearing 13 can adopt ball bearing or agglomerated material is pressed into the bearing in the resin enclosure or resin enclosure and bearing made the structure that is integral, is made of inside diameter 13a that is used for support figure abridged back shaft and chimeric the fixedly chimeric fixed part 13b of lip seal 12.
Lip seal 12 allows the ring stiffener 14 of formations such as SPC material be shaped simultaneously at the outer diameter part that inside diameter is provided with the annular seal 12b that the rubber of the NBR of lip 12a makes.Ring stiffener 14 is the needed parts of roundness that are used to keep lip 12a.
Bearing arrangement 10 is fixed on the ring stiffener 14 of lip seal 12 among the chimeric fixed part 13b of bearing 13 chimericly.The tip of the lip 12a of lip seal 12 and the sliding contact of back shaft side face thus, can prevent developer intrusion bearing inside.
But, above-mentioned bearing arrangement 10 in the past, because long-term use continuously, developer still can leak the bearing portion that invades from sealing.Thereby, the rotary torque instability of roller.In addition, also brought the be much obliged problem of the internal diameter abrasion under the condition of resin shaft.
In addition, lip seal 12 must add combined shapings such as sulphur shaping to annular seal 12b and the ring stiffener 14 that rubber is made, thereby manufacturing process's complexity has brought Master Cost the problem that cost is raised such as to increase.
Moreover for the withdrawal force that guarantees that lip seal 12 is not extracted from bearing 13, bearing 13 need carry out chimeric with the power more than the 10N with lip seal 12 at least.Thereby bearing 13 must be guaranteed the wall thickness t of chimeric fixed part 13b 2More than set-point, more than for example about 1.5mm, the drawback that this has brought the physical dimension of bearing 13 to maximize simultaneously, has also produced the chimeric adjustment difficulty of chimeric fixed part 13b and ring stiffener 14, needs problems such as high-precision component management.
The present invention is exactly in view of the above problems and proposes, and its objective is that the rotary torque that a kind of roller is provided can not change, can eliminate problem such as bearing wear, not need the roller of high-precision component management to support to use bearing.
The invention provides a kind of bearing device for roller support; comprise: bearing and be used to protect the lip seal of this bearing inside; it is characterized in that; lip seal is made up of elastomeric integrally formed parts; these integrally formed parts are by constituting with the lip of the side face sliding contact that is supported in the back shaft on the bearing and the fixed part that is fixed on the bearing, and this fixed part is fitted in the bearing with being pressed into.Here, so-called elastomeric integrally formed parts are meant the elastic body molded component of formation separately except the complex of metal parts etc.In addition, what is called protection bearing inside is meant and does not allow foreign matter invade in the sliding contact surface of bearing and axle.
In addition, above-mentioned bearing is the bearing that the bearing made of synthetic resin or oil-containing sintered alloy are made.
The invention provides the bearing device for roller support that a kind of display is used, comprise shell, be used for rotatably supporting and be used to transfer and stir the roller that is contained in the developer in this shell, it is characterized in that, this bearing device for roller support is such bearing device for roller support: by constituting lip seal with lip that is fitted to the back shaft side face sliding contact in the bearing and the fixed part that is fixed on the bearing, this fixed part is fitted in the bearing with being pressed into.In addition, above-mentioned bearing is the bearing that the bearing made of synthetic resin or oil-containing sintered alloy are made.
Moreover, being used for the bearing device for roller support of above-mentioned display, bearing being arranged on the shell, the fixed part of above-mentioned lip seal is fitted in the shell with being pressed into.
Because the lip seal of bearing device for roller support, by constituting with lip that is fitted to the back shaft side face sliding contact in the bearing and the fixed part that is fixed on the bearing, this fixed part is fitted in the bearing with being pressed into, in addition, lip seal is made of elastomeric integrally formed parts, compare with lip seal in the past, can make the independent structure member of the ring stiffener of no SPC material etc.In addition, be pressed into, keep being easy to carrying out by elastomeric integrally formed parts being fitted in the bearing with being pressed into, can making.Moreover, because at the periphery of lip fixing ring stiffener not, thereby the degree of freedom when having improved with the sliding contact of back shaft side face has reduced sliding contact power, has suppressed the change of rotary torque.
The simple declaration of accompanying drawing
Fig. 1 is the sectional drawing of bearing arrangement.
Fig. 2 is the A portion amplification profile diagram of Fig. 1.
Fig. 3 is the sectional drawing of lip seal.
Fig. 4 is the sectional drawing of bearing.
Fig. 5 is the sectional drawing of bearing arrangement in the past.
Fig. 6 is the sectional drawing of lip seal in the past.
Fig. 7 is the sectional drawing of bearing in the past.
Fig. 8 is the skeleton diagram of display.
Fig. 9 is the B portion enlarged drawing of Fig. 8.
An example of the employed bearing device for roller support of display is described below by Fig. 1～Fig. 4.Fig. 1 is the sectional drawing of bearing arrangement, and Fig. 2 is the A portion amplification profile diagram of Fig. 1, and Fig. 3 is the sectional drawing of lip seal, and Fig. 4 is the sectional drawing of bearing.
Bearing arrangement 1 is made of bearing 2 and lip seal 3.Bearing 2 is formed for the chimeric fixed part 2b of chimeric fixedly lip seal 3 in the end of the bearing body part 2a of the back shaft 4 that is used for agitating roller shown in the support figure dotted line etc.Lip seal 3 can prevent the inside of developer intrusion bearing body part 2a, protection bearing body.
Bearing body part 2a can use any of swivel bearing or sliding bearing.Under the situation of bearing that uses synthetic resin to make or the sliding bearing is made up of the oil-containing sintered alloy, the instability of the caused rotary torque of intrusion of Powdered developer, the problems such as abrasion value increase of bearing bore diameter are easy to generation.Therefore, positive good utilisation bearing arrangement of the present invention.In addition, the occasion of the sliding bearing of making at synthetic resin particularly is easy to outer shell integrated with display.For example, the cell wall that holds the shell of Powdered developer is provided with through hole, constitutes bearing body part 2a according to this.In this case, the directly tip portion of set through hole formation on shell of chimeric fixed part 2b.
It is proper that formed chimeric fixed part 2b makes the shape that can be pressed into lip seal 3 chimericly in the end of bearing 2.As an example, the diameter d of chimeric fixed part 2b 1Set body diameter d for less than lip seal 3 2Form.(d 2-d 1) size in the regime of elastic deformation of the lip seal 3 that elastomeric integrally formed parts are formed, more suitable in withdrawal force is scope more than the 10N at least.By means of setting withdrawal force more than 10N, can make lip seal 3 with back shaft 4 rotations, prevent extracting of this lip seal 3.In addition, also can on chimeric fixed part 2b, be provided with lip seal 3 be pressed into the chimeric concaveconvex shape of telescoping part.For example, as shown in Figure 4, can be provided with and be pressed into groove 2c and 2d.Be pressed into groove 2c for the round shape of the axle centres of back shaft 4, and have given groove length in the shaft centre line direction.In addition, be pressed into groove 2d for the round shape of axle centres, and be provided with given groove length in radial direction.The lip seal of being made up of elastomeric integrally formed parts 3 is pressed into these and is pressed among groove 2c and the 2d, thus, even metal ring stiffener that need not be in the past also can make withdrawal force more than 10N.Particularly, be pressed into the inner and outer diameter of groove 2c, the length of axis direction, can more easily adjust withdrawal force according to the convex-concave shape adjustment of lip seal 3.Its reason is that the width w of lip seal 3 is by the restrictions such as size of lip, if only utilize (d 2-d 1) size control withdrawal force, can make lip seal 3 produce distortion etc., reduced the right alignment of lip, thereby be inappropriate.
Lip seal 3 is made by the elastomeric integrally formed parts with caoutchouc elasticity.As shown in Figure 3, wholely do circlewise lip seal 3 by constituting with the lip 3a of the side face sliding contact of back shaft 4 and the fixed part 3b that is fixed in the bearing.On this fixed part 3b, form protuberance 3c and 3d with the chimeric usefulness of above-mentioned chimeric fixed part 2b.Protuberance 3c and 3d have can be fitted to the above-mentioned protuberance width greater than each groove width that is pressed among groove 2c and the 2d with being pressed into.
As shown in Figure 2, the protuberance 3c of lip seal 3 and 3d are fitted to being pressed among groove 2c and the 2d of bearing 2 with being pressed into respectively, obtain bearing arrangement 1 thus.Lip seal 3 is elastomeric integrally formed parts, thereby, be easy to carry out chimeric with being pressed into, in addition, since formed the withdrawal force when keeping assembling protuberance 3c and 3d, be pressed into groove 2c and 2d, thereby the confining force that is pressed into fitting portion has obtained reinforcement, even lip seal 3 common rotations etc. can not pulled out yet.And then, be pressed under the chimeric situation, act on the pressure of the load on the chimeric fixed part 2b of bearing 2, compare more weak with the ring stiffener of metal ring in the past.As a result, bearing end portion thickness t 1Can be thinner, the degree of about 8mm for example.
The present invention is applicable to bearing device for roller support, and this bearing device for roller support supports to stir agitating roller that is contained in the developer in the display video picture groove and at least one roller of developer being supplied with the developing roll of photosensitive drums free to rotately.These rollers and developer are disposing contiguously, still, adopt bearing arrangement of the present invention, can suppress the intrusion of developer to bearing bore diameter, thereby, can make the rotary torque stabilization of roller.
Embodiment 1
Below, according to the bearing device for roller support of example application explanation display.
The developer of micronized (toner) is contained in the display, and the agitating roller that is used to stir developer is installed on this display.The bearing device for roller support that agitating roller is made by the resin that is configured in its both ends is being supported.Bearing device for roller support, its bearing are the resin molded body of polyformaldehyde resin (POM) material, and its lip seal is the elastomeric seal that the integrally formed parts of nitrile rubber (NBR) constitute.
Bearing device for roller support as shown in Figure 1, lip seal is fitted in the bearing with being pressed into, and this lip seal is installed on the shell of display shown in Figure 8, and this lip seal is configured in the video picture groove between the bearing with the support agitating roller.In addition, before bearing arrangement is installed on the shell, lip seal is fitted in the bearing with being pressed into.The back shaft of agitating roller is not have the electrolytic nickel electroplating processes on the surface of automatic steel (SUM).
Utilizing this display, is the speed setting of agitating roller that 300rpm, load are set at 50N, carries out actual long duration test.(0 hour) before on-test and the characteristic after 50 hours are estimated.The evaluating characteristics project has or not with visual judgement friction factor and developer leakage etc.Evaluation result is shown in the table 1.
Comparative example 1
Comparative example 1 as bearing device for roller support, except adopting bearing arrangement shown in Figure 5, also needs the display with the same formation of embodiment, and the characteristic identical with embodiment 1 estimated.In addition, bearing device for roller support, its bearing is the resin molded body with the polyformaldehyde resin that is pressed into telescoping part (POM) material of no convex-concave shape, its lip seal makes the structure that the outer diameter part of the elastomeric seal that makes ring stiffener that the SPCE material constitutes and nitrile rubber (NBR) is shaped simultaneously, and this ring stiffener is fitted in the bearing with partly being pressed into.Its evaluation result is shown in the table 1.
Comparative example 2
Except the material of bearing is the oil-containing sintered alloy, adopt the display with comparative example 1 identical formation, the characteristic identical with embodiment 1 estimated.Its evaluation result is shown in the table 1.
[table 1]
Project Embodiment 1 Comparative example 1 Comparative example 2
Friction factor 0 hour ???0.14 ???0.15 ???0.19
50 hours ???0.14 ???0.17 ???0.19
What developer leaked after 50 hours has or not Do not have Do not have Do not have
As shown in table 1, the friction co-efficient value minimum of embodiment 1 in addition, after 50 hours, does not change yet.As a result, eliminated the change of turn-knob square.
The invention effect
The present invention is owing to be fitted to the fixed part of the lip packing of elastomeric integrally formed parts composition in the bearing with being pressed into, thereby, can dwindle the load that acts on the bearing. As a result, can make the thickness attenuation of bearing end, realize the miniaturization of bearing arrangement. In addition, because lip packing is integrally formed parts, and then can reduce manufacturing process, reduce the cost of bearing arrangement.
Moreover, because bearing is that synthetic resin is made or the bearing made of oil-impregnated sintered alloy, thereby, be easy to integrally formed. As a result, when lip packing is integrally formed, can reduce the cost of bearing arrangement.
The present invention is owing to be the bearing device for roller support that is used for above-mentioned back shaft in the display, thereby, not only simple in structure, and can prevent that developer from leaking or invading the bearing portion from sealing, can eliminate the change of the rotation torque of back shaft.
Moreover bearing is arranged on the shell of display, and the fixed part of lip packing is fitted on the shell with being pressed into, and then, can realize the miniaturization of display.

Claims (4)

1. bearing device for roller support; comprise: bearing and be used to protect the lip seal of this bearing inside; it is characterized in that; described lip seal is made up of elastomeric integrally formed parts; these integrally formed parts are by constituting with the lip of the side face sliding contact that is supported in the back shaft on the described bearing and the fixed part that is fixed on the described bearing, and this fixed part is fitted in the described bearing with being pressed into.
2. bearing device for roller support according to claim 1 is characterized in that, described bearing is the bearing that the bearing made of synthetic resin or oil-containing sintered alloy are made.
3. the bearing device for roller support of a display, comprise shell, be used for rotatably supporting and be used to transfer and stir the roller that is contained in the developer in this shell, it is characterized in that this bearing device for roller support is claim 1 or the described bearing device for roller support of claim 2.
4. bearing device for roller support according to claim 3 is characterized in that, described bearing is arranged on the described shell, and the fixed part of described lip seal is fitted in the described shell with being pressed into.
CNB011213310A 2000-06-02 2001-05-31 Bearing device for roller support Expired - Fee Related CN1196980C (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP165536/2000 2000-06-02
JP2000165536A JP4105370B2 (en) 2000-06-02 2000-06-02 Roller support bearing device

Publications (2)

Publication Number Publication Date
CN1327179A true CN1327179A (en) 2001-12-19
CN1196980C CN1196980C (en) 2005-04-13

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CNB011213310A Expired - Fee Related CN1196980C (en) 2000-06-02 2001-05-31 Bearing device for roller support

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CN (1) CN1196980C (en)

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CN102147012A (en) * 2010-02-08 2011-08-10 富士施乐株式会社 Bearing seal unit, and developing device and image forming device using bearing seal unit
CN103329203A (en) * 2011-01-05 2013-09-25 株式会社三弘社 Spindle motor
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US7583923B2 (en) 2004-05-06 2009-09-01 Samsung Electronics Co., Ltd. Bearing structure and fusing device for image forming apparatus employing the bearing structure
JP2007187234A (en) * 2006-01-13 2007-07-26 Nabtesco Corp Oil seal
JP5202928B2 (en) * 2007-11-20 2013-06-05 バンドー化学株式会社 Toner seal compound bearing
JP4893871B1 (en) * 2011-08-08 2012-03-07 富士ゼロックス株式会社 Bearing / sealing seal member, developing device and image forming apparatus using the same
JP5661954B2 (en) * 2011-11-09 2015-01-28 キヤノン株式会社 Developer container and process cartridge
JP6128596B2 (en) * 2013-07-29 2017-05-17 イーグルブルグマンジャパン株式会社 Sealing device
DE102014000197A1 (en) * 2014-01-14 2015-07-16 Schwing Gmbh Mounting a rotating shaft with sealing ring
JP6709722B2 (en) * 2016-11-24 2020-06-17 株式会社ダイヤメット Sintered bearing
JP2019044817A (en) * 2017-08-31 2019-03-22 アルプス電気株式会社 Airtight holding mechanism and position detection device for stand
JP7089738B2 (en) * 2018-04-27 2022-06-23 株式会社横井製作所 Bearing member
JP2021095931A (en) * 2019-12-13 2021-06-24 株式会社リコー Bearing member, carrying device and image formation device
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102147012A (en) * 2010-02-08 2011-08-10 富士施乐株式会社 Bearing seal unit, and developing device and image forming device using bearing seal unit
CN102147012B (en) * 2010-02-08 2016-03-30 富士施乐株式会社 Bearing seal unit and use developing device and the image forming apparatus of this unit
CN103329203A (en) * 2011-01-05 2013-09-25 株式会社三弘社 Spindle motor
CN112135980A (en) * 2018-05-23 2020-12-25 大冶美有限公司 Sintered bearing
US11353063B2 (en) * 2018-05-23 2022-06-07 Diamet Corporation Sintered bearing

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Publication number Publication date
JP2001349326A (en) 2001-12-21
JP4105370B2 (en) 2008-06-25
CN1196980C (en) 2005-04-13

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