JP6980244B2 - Torque limiter and separation mechanism - Google Patents

Description

The present invention relates to a torque limiter and a separation mechanism.

In a torque limiter consisting of a rotating member and a torque generating means that applies a predetermined torque to the rotation of the rotating member, the torque limiter in which a surface treatment portion having a required friction coefficient is formed on the outer surface of the rotating member is known. (Patent Document 1).

It is a rotation transmission device that transmits torque between an inner rotating body and an outer rotating body that are coaxially rotatably provided with respect to each other by hysteresis torque. The inner rotating body is made of a semi-hard magnetic material and rotates outward. The body includes a bearing portion that is in sliding contact with the outer peripheral portion of the inner rotating body and a cylindrical inner peripheral portion that faces the outer peripheral portion of the inner rotating body at a distance. A rotation transmission device to which a cylindrical permanent magnet having at least its inner peripheral surface magnetized with multiple poles is fixed is also known (Patent Document 2).

Japanese Unexamined Patent Publication No. 2009-190888 Japanese Unexamined Patent Publication No. 2005-147296

The present invention provides a torque limiter integrally provided with an elastic body capable of suppressing an increase in the amount of change in outer diameter, and a separation mechanism capable of suppressing a deterioration in separation performance for a long period of time by using the torque limiter. With the goal.

In order to solve the above problems, the torque limiter according to claim 1 is used.
A first rotating body having a cylindrical outer peripheral portion made of a permanent magnet,
A second rotating body having a cylindrical inner peripheral portion made of a hysteresis material facing the cylindrical outer peripheral portion and provided coaxially with the first rotating body and rotatably relative to each other.
The ratio E1 (22 ° C) / tan δ (22 ° C) of the dynamic elastic modulus E1 (22 ° C) and the loss tangent tan δ (22 ° C) fixed to the outer peripheral portion of the second rotating body is 30 MPa or more and 44.3 MPa. The following is an elastic body having a dynamic elastic modulus E1 (22 ° C.) of 1.0 MPa or more and 1.95 MPa or less.
With,
Torque limiter characterized by that.

The invention according to claim 2 is the torque limiter according to claim 1.
The hysteresis material has circumferential anisotropy.
It is characterized by that.

In order to solve the above problems, the separation mechanism according to claim 3 is used.
A paper feed roller that applies feeding force to the sheet material to be sent out,
The torque limiter according to claim 1 or 2, which separates the sheet material other than the uppermost sheet material among the plurality of sheet materials sent out by pressure contacting the paper feed roller, is provided.
It is characterized by that.

The invention according to claim 4 is the separation mechanism according to claim 3.
The paper feed roller provided with the elastic body.
It is characterized by that.

According to the first aspect of the present invention, it is possible to suppress an increase in the amount of change in the outer diameter of the torque limiter integrally provided with an elastic body and to suppress double feeding of paper in the separation mechanism.
According to the second aspect of the present invention, the torque limiter can be miniaturized by increasing the hysteresis torque of the torque limiter and reducing the variation of the initial torque.
According to the third aspect of the present invention, the life can be extended while the separation mechanism can be miniaturized.
According to the invention of claim 4, the wear of the paper feed roller can be suppressed.

It is a vertical cross-sectional schematic diagram of a torque limiter. (A) is a schematic diagram showing a magnetic field processing method of a flat plate-shaped hysteresis material, (b) is a schematic diagram showing a direction of magnetic field processing, and (c) is a diagram showing a circumferential anisotropy hysteresis material. (A) is a schematic cross-sectional view of a paper feed device including a separation mechanism using a torque limiter, (b) is a schematic cross-sectional view showing the operation of the separation mechanism when separating a plurality of sheets of paper, and (c) is a simple cross-sectional view. It is sectional drawing which shows the operation of the separation mechanism at the time of transporting a sheet of paper. It is a figure which shows the result of having measured the maximum torque of the torque limiter of an Example and a comparative example. It is a figure which shows the mechanical property, viscoelastic property of the rubber composition which concerns on Examples 1 to 4 and Comparative Example 1, and the paper passing evaluation result of the separation mechanism using the said rubber composition. It is a figure which shows the relationship between E1 (22 ° C.) / tan δ (22 ° C.) in Examples 1 to 4 and Comparative Example 1 and the amount of change in the outer diameter of a retard roller. It is a figure which shows the relationship between the viscoelastic property and the amount of change in the outer diameter in Comparative Examples 1-3.

Next, with reference to the drawings, embodiments and specific examples will be given below to explain the present invention in more detail, but the present invention is not limited to these embodiments and specific examples.
In addition, in the explanation using the following drawings, it should be noted that the drawings are schematic and the ratio of each dimension is different from the actual one, which is necessary for the explanation for easy understanding. Illustrations other than the members are omitted as appropriate.

(1) Configuration of Torque Limiter FIG. 1 is a schematic cross-sectional view of the torque limiter 1 according to the present embodiment, FIG. 2A is a schematic diagram showing a magnetic field processing method for a flat plate-shaped hysteresis material, and FIG. 2B is a magnetic field processing diagram. The schematic diagram which shows the direction, (c) is the figure which shows the hysteresis material of the circumferential anisotropy.
The torque limiter 1 includes a first rotating body 10 and a second rotating body 20. One end side of the first rotating body 10 is rotatably supported by one end side of the second rotating body 20, and the other end side of the first rotating body 10 is rotatably supported by the second rotating body 20 via a lid 40. Has been done.

(1.1) First Rotating Body The first rotating body 10 is configured by fixing a hollow shaft 11 and a permanent magnet 12 as an example of a cylindrical outer peripheral portion to the outer peripheral surface of the shaft 11.
As an example, the shaft 11 is made of a synthetic resin material, and specific examples thereof include polyacetal (POM), polypropylene (PP), polycarbonate (PC), and polyamide (PA).

The permanent magnet 12 is preferably multi-pole magnetized, specifically, the ferrite magnet or the rare earth magnet is multi-pole magnetized (14 poles in this embodiment). From the viewpoint of miniaturization and high torque of the torque limiter, it is preferable to use a rare earth magnet, and examples of the rare earth magnet include Nd-Fe-B magnets, Sm-Fe-N magnets, and Sm-Co magnets.
By magnetizing the permanent magnets with multiple poles, it is possible to suppress the torque ripple of the hysteresis torque generated between the first rotating body 10 and the second rotating body 20.

(1.2) Second rotating body The second rotating body 20 is an example of a hollow housing 21 and a cylindrical inner peripheral portion fixed to a portion of the inner peripheral surface of the housing 21 facing the permanent magnet 12. It is composed of a hysteresis material 22 and a rubber layer 30 as an example of an elastic body fixed to the outer peripheral surface of the housing 21.

(1.2.1) Hysteresis Material Hysteresis Material 22 applies a specific magnetic field treatment to a semi-hard magnetic material selected from the group consisting of Fe-Cr-Co, Fe-Mn, Al-Ni, and Al-Ni-Co. Formed by doing.
Specifically, the hot-rolled and cold-rolled semi-hard magnetic material is cut into a flat plate shape (rectangular shape), and as shown in FIG. 2A, the obtained flat plate-shaped semi-hard magnetic material is obtained. With the bodies 220 stacked and arranged in the magnetic field processing machine 300, the magnetic field processing is performed with the magnetic field orientation direction set to a fixed direction (see arrow B in the figure) as shown in FIG. 2 (b). Then, the flat plate-shaped semi-rigid magnetic material 220 is bent into a cylindrical shape, polished, and then aged.
By such a processing method, a cylindrical hysteresis material 22 that is anisotropic in the circumferential direction (circumferential anisotropy) as shown in FIG. 2C can be obtained.

Since the hysteresis material 22 has anisotropy in the circumferential direction, the hysteresis torque of the torque limiter 1 is increased, and the torque limiter 1 can be further miniaturized.
Further, the hysteresis material 22 having circumferential anisotropy can obtain regular anisotropy by a method of magnetically treating a flat plate-shaped semi-rigid magnetic material 220, and when a plurality of them are manufactured in large quantities at one time, per lot. The variation in the initial torque of the torque limiter 1 can be suppressed to be smaller.

(1.2.2) Rubber layer The rubber layer 30 has a ratio E1 (22 ° C.) / tanδ (22 ° C.) of a dynamic elastic modulus E1 (22 ° C.) and a loss tangent tanδ (22 ° C.) of 20 MPa or more. It comprises a rubber composition having a dynamic elastic modulus E1 (22 ° C.) of 1.0 MPa or more and 10 MPa or less. Further, it is preferable that the ratio E1 (22 ° C.) / tan δ (22 ° C.) of the dynamic elastic modulus E1 (22 ° C.) and the loss tangent tan δ (22 ° C.) is 30 MPa or more.
The dynamic elastic modulus E1 (22 ° C.) is a value of the dynamic elastic modulus E1 when the measured temperature is 22 ° C. at room temperature, which is obtained by measuring the temperature dispersion of the dynamic viscoelasticity.
The loss tangent tan δ (22 ° C.) is the value of the loss tangent tan δ when the measured temperature is 22 ° C. at room temperature, which is obtained by the temperature dispersion measurement of dynamic viscoelasticity.

When the rubber composition of the rubber layer 30 has a ratio E1 (22 ° C.) / tanδ (22 ° C.) of the dynamic elastic modulus E1 (22 ° C.) and the loss tangent tan δ (22 ° C.) of 20 MPa or more, the torque limiter 1 When used in the separation mechanism, it is possible to suppress an increase in the amount of change in the outer diameter due to wear of the rubber layer 30 of the torque limiter 1.

The dynamic elastic modulus E1 (22 ° C.) is 1.0 MPa or more and 10 MPa or less. When the dynamic elastic modulus E1 (22 ° C.) is smaller than 1.0 MPa, the wear resistance of the rubber layer 30 is lowered and the amount of change in the outer diameter is large. When the dynamic elastic modulus E1 (22 ° C.) is larger than 10 MPa, the initial friction coefficient is low when used in the separation mechanism, and the torque limiter 1 when one sheet of paper P is conveyed to the nip portion N There is a risk that the forward rotation will deteriorate and uneven wear of the rubber layer 30 and abnormal noise will occur (see FIG. 3 (c)). Further, the friction coefficient between the rubber layer 30 and the paper P is lower than the friction coefficient between the papers, and there is a possibility that double feeding may occur when two or more sheets of paper P are conveyed to the nip portion N. (See FIG. 3 (b)).

The loss tangent tan δ (22 ° C.) is preferably 0.01 or more and 0.1 or less. When the loss tangent tan δ (22 ° C.) is smaller than 0.01, the amount of filler in the rubber composition is small, and the composition has a high crosslink density, so that the mechanical strength is reduced and the rubber layer 30 may be broken. be.
When the loss tangent tan δ (22 ° C.) is larger than 0.1, the friction (loss) between the polymer main chains, between the polymer main chains and the filler, and between the fillers generated when the rubber layer 30 is deformed becomes large. Abrasion resistance may decrease.

The rubber layer 30 is not particularly limited as long as it is a rubber material, but specifically, it is preferable that the rubber layer 30 contains ethylene propylene copolymer rubber (EPDM) as a main component.
Examples of rubber materials other than EPDM include natural rubber, isoprene rubber, butadiene rubber, butyl rubber, styrene butadiene rubber, polynorbornene rubber, butadiene-nitrile rubber, chloroprene rubber, halogenated butyl rubber, acrylic rubber, and epichlorohydrin rubber. At least one may be included.
When EPDM is used as the rubber material, EPDM may be either non-oil-extended grade or oil-extended grade, or may be a mixture of non-oil-extended grade and oil-extended grade.

(2) Configuration of Separation Mechanism FIG. 3A is a schematic cross-sectional view of a paper feed device including a separation mechanism using a torque limiter, and FIG. 3B shows the operation of the separation mechanism when separating a plurality of sheets of paper. A schematic cross-sectional view, (c) is a schematic cross-sectional view showing the operation of the separation mechanism when transporting a single sheet of paper.
The paper feed device 100 includes a paper cassette 110 loaded with paper P as a sheet material, a nager roller 120 that comes into contact with the tip end side of the upper surface of the paper P and feeds out the paper P from the paper cassette 110, and paper fed from the nager roller 120. It includes a separation mechanism 50 that separates (separates) P one by one and conveys them.

A separation mechanism 50 is arranged on the downstream side of the nager roller 120 in the paper transport direction. The separation mechanism 50 is from a torque limiter 1 provided with a feed roller 2 as an example of a paper feed roller and a rubber layer 30 as a retard roller arranged by pressure contact with the feed roller 2 on the lower side of the feed roller 2. A nip portion N is formed between the feed roller 2 and the torque limiter 1 to hold the paper P fed from the paper cassette 110.

In the feed roller 2, the rubber layer 2b is fixed to the outer peripheral surface of the hollow core material 2a through which the rotating shaft for transmitting the driving force is inserted.
The rubber layer 2b is preferably made of the same rubber composition as the rubber layer 30 of the torque limiter 1. Specifically, the rubber layer 2b has a dynamic elastic modulus E1 (22 ° C.) and a loss tangent tanδ (22 ° C.) ratio E1 (22 ° C.) / tanδ (22 ° C.) of 20 MPa or more, and has a dynamic elastic modulus. It comprises a rubber composition having an E1 (22 ° C.) of 1.0 MPa or more and 10 MPa or less.

The feed roller 2 is a drive roller that is rotationally driven around this axis by a drive source (not shown) with a direction orthogonal to the paper transport direction as an axial direction. The feed roller 2 is fed from the paper cassette 110 and has a nip portion. The paper P is conveyed downstream by abutting on the upper surface (surface) of the paper P conveyed to N and being driven to rotate (see arrow R in the figure).

The torque limiter 1 is a retard roller whose axial direction is orthogonal to the paper transport direction and rotates in the reverse direction while being pressed against the feed roller 2 around this axis by a drive source (not shown), and a plurality of sheets of paper P are overlapped with each other. When the paper P is conveyed to the nip portion N, a transfer resistance is applied to the paper P from the lower surface side (back surface side) to suppress double feeding of the paper P conveyed by the feed roller 2 (see FIG. 3 (b)). ).
When one sheet of paper P is conveyed to the nip portion N, the paper P comes into contact with the surface of the feed roller 2, and when a rotational force is applied to the torque limiter 1 by friction with the paper P, torque is applied. The limiter 1 is driven to rotate and the paper P is conveyed downstream (see FIG. 3C).
The torque limiter 1 may be a driven roller that rotates around an axis without being applied with a driving force of reverse rotation.

As described above, in the separation mechanism 50, the torque limiter 1 functions as a brake, so that when a plurality of sheets P are overlapped and conveyed to the nip portion N, the sheets P are transferred from the lower surface side (back surface side) to the sheets P. A transfer resistance is provided to suppress double feeding of the paper P conveyed by the feed roller 2.

In the separation mechanism 50, the torque limiter 1 that transmits torque by hysteresis torque based on the hysteresis loss has higher durability than the spring type torque limiter, and the durability of the rubber layer 30 fixed to the outer peripheral surface of the housing 21 is high. If the property is low, the separation performance may be deteriorated and the life of the separation mechanism 50 may be shortened even though the transmission torque is maintained.

In the separation mechanism 50 using the torque limiter 1 according to the present embodiment as a retard roller, the torque limiter 1 that collaborates with the feed roller 2 while collaborating to separate a plurality of sheets of paper P has a dynamic elastic modulus E1 (a dynamic elastic modulus E1. When the ratio E1 (22 ° C.) / tanδ (22 ° C.) of 22 ° C.) and the loss tangent tanδ (22 ° C.) is 20 MPa or more, and the dynamic elastic modulus E1 (22 ° C.) is 1.0 MPa or more and 10 MPa or less. It includes a rubber layer 30 made of a certain rubber composition.
Therefore, it is possible to suppress an increase in the amount of change in the outer diameter due to wear of the rubber layer 30 of the torque limiter 1 and extend the replacement life of the torque limiter 1.

"Creating a torque limiter"
The first rotating body 10 was fixed by inserting a permanent magnet 12 having an outer diameter of 14.37 mm, an inner diameter of 11.47 mm, a number of magnetic poles of 14 poles, and a magnetizing pitch of 3.22 mm into the hollow shaft 11.
The second rotating body 20 was fixed by inserting a circumferential anisotropic hysteresis material having an outer diameter of 15.60 mm and an inner diameter of 14.80 mm into the housing 21. Further, a torque limiter of a comparative example using a radially anisotropic hysteresis material having an outer diameter of 15.60 mm and an inner diameter of 14.80 mm was also created.
In the torque limiter in this embodiment and the comparative example, the materials and dimensions of each component are the same except for the orientation direction of the magnetic field of the hysteresis material.

"Maximum torque evaluation of torque limiter"
FIG. 4 is a diagram showing the results of measuring the maximum torque by creating 15 torque limiters for each of the examples and the comparative examples.
The maximum torque of the torque limiter of the comparative example was 314 gfcm at the maximum, the minimum value was 278 gf cm, and the variation was 36 gfcm. On the other hand, the maximum torque of the torque limiter of the example was 326 gfcm at the maximum, the minimum value was 312 gfcm, and the variation was 14 gfcm.

From this result, the torque limiter of the example using the circumferential anisotropic hysteresis material has a larger initial torque and smaller variation than the torque limiter of the comparative example using the radial anisotropic hysteresis material. Was shown. Therefore, in the torque limiter of the embodiment using the circumferential anisotropic hysteresis material, the hysteresis torque increases, the torque limiter can be further miniaturized, and the rubber layer 30 is arranged on the outer surface of the torque limiter. It is suitable for configuring a retard roller with a built-in.

"Creation of rubber composition"
The rubber composition of the rubber layer 30 of the torque limiter 1 according to the present embodiment includes a predetermined amount of polymer component, a cross-linking agent, and if necessary, a predetermined amount of softener, filler, other vulcanization accelerator, and vulcanization. An unvulcanized rubber composition is obtained by kneading a compound consisting of an accelerating aid and an additive such as an antiaging agent using a kneader, and this is placed in a predetermined mold at 160 ° C. and 30 ° C. After vulcanization molding under the condition of 1 minute, the secondary vulcanization was further carried out under the condition of 160 ° C. for 60 minutes.

Then, the formed rubber tube is polished with a cylindrical polishing machine to a desired outer diameter, cut to a desired length, and then inserted as a rubber layer 30 into the outer peripheral surface of the housing 21 as shown in FIG. , The torque limiter of the example and the comparative example provided with the rubber layer 30 was prepared.

"Measurement of viscoelastic properties"
Using a kneader, a predetermined amount of polymer components, a cross-linking agent, and, if necessary, a predetermined amount of softeners, fillers, other vulcanization accelerators, vulcanization accelerator aids, and additives such as antiaging agents. The composition was kneaded, vulcanized and molded using a mold under the conditions of 160 ° C. for 30 minutes, and further secondary vulcanized under the conditions of 160 ° C. for 60 minutes. As a result, a sheet-shaped rubber crosslinked product was obtained. A strip-shaped sample having a width of 5 mm, a length of 20 mm, and a thickness of 2 mm was punched from this sheet to obtain a rubber composition for measuring viscoelastic properties.
The viscoelastic property (temperature dispersion) of the punched sample is based on JISK6394 (dynamic property test method for vultured rubber and thermoplastic rubber / small test device), and is a dynamic viscoelasticity measuring device (manufactured by UBM). It was measured under the following measurement conditions using Rheogel E4000FHP).
Measurement temperature: -84 ° C to 120 ° C
Measurement temperature temperature rise rate: 2 ° C / min
Measurement temperature interval: 1 ° C
Measurement frequency: 10Hz
Initial distortion: 1.3 mm
Amplitude: 2 μm
Deformation mode: Tensile chuck distance 10 mm
Waveform: sine wave

From the measurement results of each of the prepared samples, the values of the dynamic elastic modulus E1 (22 ° C.) and the values of the loss tangent tan δ (22 ° C.) were read.

"Paper test"
A torque limiter provided with the rubber layer 30 of Examples and Comparative Examples was attached to DocuPrint 4050 (manufactured by Fuji Xerox Co., Ltd.), and the paper "Busines 4200" (manufactured by Xerox Co., Ltd.) was applied to 50,000 sheets in a temperature of 10 ° C. and a humidity of 15% RH. I passed the paper over. The measurement is performed at the time of 5,000 sheets, 10,000 sheets, 20,000 sheets, 30,000 sheets, 40,000 sheets, and 50,000 sheets after the start of the paper passing test, and the outer diameter change amount [mm] is measured in a temperature of 10 ° C. and a humidity of 15% in an RH environment. did.
Here, the "outer diameter change amount" is the rubber layer of the initial torque limiter 1 (retard roller) from the outer diameter of the rubber layer 30 of the torque limiter 1 (retard roller) after passing a predetermined number of sheets of paper. It is a value obtained by subtracting the outer diameter of 30. The smaller the absolute value of the outer diameter change amount, the more difficult it is for the rubber layer 30 to be scraped, indicating that the wear resistance is excellent.

"Evaluation of viscoelastic properties and paper passing performance"
FIG. 5 is a diagram showing the mechanical properties and viscoelastic properties of the rubber compositions according to Examples 1 to 4 and Comparative Example 1, and the paper passing evaluation of the separation mechanism 50 using the rubber composition, and FIG. 6 is a diagram showing Example 1 -4 and the ratio of the dynamic elastic modulus E1 (22 ° C.) to the loss tangent tan δ (22 ° C.) in Comparative Example 1 E1 (22 ° C.) / tan δ (22 ° C.) and the rubber layer 30 of the torque limiter 1 (retard roller). FIG. 7 is a diagram showing the relationship with the amount of change in the outer diameter, and FIG. 7 is a diagram showing the relationship between the viscoelastic property and the amount of change in the outer diameter in Comparative Examples 1 to 3.

From the results shown in FIGS. 5 and 6, in the measurement of viscoelastic properties, the ratio E1 (22 ° C) / tan δ (22 ° C) of the dynamic elastic modulus E1 (22 ° C) and the loss tangent tan δ (22 ° C) is 20 [ It was found that when it was more than MPa], the amount of change in the outer diameter of the rubber layer 30 as the retard roller was suppressed, and the life of the separation mechanism 50 was long.

The dynamic elastic modulus E1 (22 ° C.) is related to the amount of deformation of the rubber layer 30 of the feed roller 2 of the separation mechanism 50 and the torque limiter 1, and when the dynamic elastic modulus E1 (22 ° C.) is high, the feed roller 2. The amount of deformation of the rubber layer 30 of the torque limiter 1 can be suppressed, the slip relative to the paper P can be reduced, and the wear resistance can be improved.
On the other hand, by lowering the loss tangent tan δ (22 ° C.), for example, by setting the loss tangent tan δ (22 ° C.) to less than 0.1, the polymer main chain, the polymer main chain and the filler generated when the rubber layer 30 is deformed. During, the friction (loss) between the fillers can be reduced.
As a result, by forming a rubber composition that increases the ratio E1 (22 ° C.) / tanδ (22 ° C.) of the dynamic elastic modulus E1 (22 ° C.) and the loss tangent tanδ (22 ° C.), the abrasion resistance as a retard roller is obtained. It is presumed that the wear resistance could be improved.

In Comparative Example 1, the ratio E1 (22 ° C.) / tanδ (22 ° C.) of the dynamic elastic modulus E1 (22 ° C.) and the loss tangent tanδ (22 ° C.) is as small as 17.6, that is, less than 20, and is outside the feed roller. The amount of change in diameter was -0.1134 mm, and the amount of change in outer diameter of the retard roller was -0.2080, resulting in a large amount of wear.

As shown in FIG. 7, Comparative Example 2 shows a case where the ratio E1 (22 ° C.) / tan δ (22 ° C.) of the dynamic elastic modulus E1 (22 ° C.) and the loss tangent tan δ (22 ° C.) exceeds 20 MPa. Even so, the absolute value of the amount of change in the outer diameter of the retard roller may be larger than in the examples.
In Comparative Example 2, the dynamic elastic modulus E1 (22 ° C.) is as low as 0.81 [MPa]. As a result, it is presumed that the amount of deformation of the rubber layer 30 of the torque limiter 1 is large and the wear resistance is inferior.

Further, in Comparative Example 3, double feeding occurred from the initial stage of paper passing, and it could not be adopted as a retard roller. As shown in FIG. 7, as shown in FIG. 7, since the dynamic elastic modulus E1 (22 ° C.) of Comparative Example 3 is as large as 26.62 [MPa], the nip amount between the paper P and the retard roller is small, and the friction is passed. It is presumed that due to the paper, the friction coefficient between the retard roller and the paper P is lower than the friction coefficient between the papers, causing double feeding.
As a result, if the dynamic elastic modulus E1 (22 ° C.) is 1.0 MPa or more and 10 MPa or less, double feeding does not occur due to paper passing, and a rubber composition capable of suppressing the amount of change in outer diameter can be obtained. Can be done.

Although the embodiments according to the present invention have been described in detail above, the present invention is not limited to the above embodiments, and various modifications are made within the scope of the gist of the present invention described in the claims. Is possible. For example, the rubber composition constituting the rubber layer 30 is not limited to EPDM or the like, and the ratio of the dynamic elastic modulus E1 (22 ° C.) to the loss tangent tan δ (22 ° C.) is E1 (22 ° C.) / tan δ (22 ° C.). It may be a urethane rubber having a dynamic elastic modulus E1 (22 ° C.) of 1.0 MPa or more and 10 MPa or less.

1 ... Torque limiter 10 ... 1st rotating body 11 ... Shaft 12 ... Permanent magnet 20 ... 2nd rotating body 21 ... Housing 22 ... Hysteresis material 30 ... Rubber layer 40 ... lid 50 ... separation mechanism 1 ... retard roller (torque limiter)
2 ... Feed roller 100 ... Paper feed device 110 ... Paper cassette 120 ... Nager roller

Claims (4)

A first rotating body having a cylindrical outer peripheral portion made of a permanent magnet,
A second rotating body having a cylindrical inner peripheral portion made of a hysteresis material facing the cylindrical outer peripheral portion and provided coaxially with the first rotating body and rotatably relative to each other.
The ratio E1 (22 ° C) / tan δ (22 ° C) of the dynamic elastic modulus E1 (22 ° C) and the loss tangent tan δ (22 ° C) fixed to the outer peripheral portion of the second rotating body is 30 MPa or more and 44.3 MPa. The following is an elastic body having a dynamic elastic modulus E1 (22 ° C.) of 1.0 MPa or more and 1.95 MPa or less.
With,
Torque limiter characterized by that. The hysteresis material has circumferential anisotropy.
The torque limiter according to claim 1. A paper feed roller that applies feeding force to the sheet material to be sent out,
The torque limiter according to claim 1 or 2, which separates the sheet material other than the uppermost sheet material among the plurality of sheet materials sent out by pressure contacting the paper feed roller, is provided.
A separation mechanism characterized by that. The paper feed roller provided with the elastic body.
The separation mechanism according to claim 3, wherein the separation mechanism is characterized in that.

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