JP2001146925A - Torque limiter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a torque limiter capable of regulating a critical torque. SOLUTION: The torque limiter 20 is provided with, for example, an input member 2 as an inner shaft member, a coil spring 4, an output member 22 as an outer shaft member, an adjustor ring 24, and a cap 8. A protrusion 22d for locking a locking piece 4a disposed on an output side end part of the coil spring 4 is disposed on an end surface of the input side of the output member 22. The adjustor ring 24 is provide with a restricting part 24a for restricting, in the inner diameter direction, the coil spring protruded in the radial direction on an inner circumferential surface. In this torque limiter 20, the position of the adjustor ring 24 is regulated in the circumferential direction against the output member 22, and thereby, a diameter enlarging quantity of the coil spring is restricted so as to regulate the critical torque.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a torque limiter that cuts off transmission of a rotational torque when a rotational torque of a predetermined value or more is applied.

[0002]

2. Description of the Related Art A torque limiter is provided on a rotational torque transmission path from a rotary drive (motor) to a rotary operating device (roller), and when a predetermined or more rotational torque is applied, the rotary operating device idles. In this way, the transmission of rotational torque is controlled.

As shown in FIG. 9, a torque limiter 1
For example, it is a component used in a paper feeding device such as a copying machine or a printer, and is attached to a paper return roller 13 for preventing double feeding of paper.

As shown in FIGS. 10A and 10B, the paper return roller 13 is a roller for inserting paper between the paper supply roller 14 and a paper return direction (opposite to the paper supply direction). ) Via a torque limiter. On the other hand, the paper feed roller 14 is attached to a rotating shaft 16 that rotates in the paper feed direction.

As shown in FIG. 10A, the paper return roller 13 rotates in the direction opposite to the paper feed direction, and two or more papers 17 are fed between the paper return roller 13 and the paper feed roller 14. In this case, the paper 17a on the side that comes into contact with the paper return roller 13 is returned to prevent the paper 17 from being double fed. Further, as shown in FIG. 10B, when only one sheet of paper 17 is fed between the paper return roller 13 and the paper feed roller 14 (or when double feeding of paper is eliminated), The paper return roller 13 receives a rotational torque in the paper feeding direction due to friction with the paper 17, and the rotation of the rotary shaft 1 by the action of the torque limiter 1.
5 in the sheet feeding direction. Also, the paper return roller 1
3 is in direct contact with the paper feed roller 14 in the same manner as when only one sheet of paper is fed. The paper return roller 13 receives rotational torque due to friction with the paper feed roller 14, and the torque limiter 1 The idle rotation in the sheet feeding direction with respect to the rotary shaft by the action of.

Hereinafter, an example of the torque limiter will be described with reference to FIG.

The torque limiter 1 mainly includes an input member 2 as an inner shaft member, a coil spring 4, an output member 6 as an outer shaft member, and a cap 8.

The input member 2 has a cylindrical body having an insertion hole 2a for inserting the rotary shaft 15 in the axial direction, and a notch 2b for connecting with the rotary shaft 15 is formed in the input side end in the axial direction. Have been.

The coil spring 4 is a metal spring wound in a coil shape with an inside diameter that allows a coil wire to be fitted to the input member 2, and is bent at a right angle in the radial direction at an end on the output side. And has a locking piece 4a protruding therefrom.

The output member 6 is a cylindrical member capable of accommodating the input member 2 and has a connecting portion 6a on its output side end surface for connecting to an output side rotated member (for example, a paper return roller 13). . The hollow portion of the output member 6 has openings 6 in order from the input side.
b, the mounting portion 6c, and the insertion hole 6d are formed. Opening 6
b, the mounting portion 6c, and the insertion hole 6d are coaxial circular holes formed continuously in the axial direction. The opening 6b is formed on the input side with an inner diameter in which the coil spring 4 can be loosely inserted. The mounting portion 6c is formed with an inner diameter capable of slidably holding the input member 2 behind the opening 6b. The insertion hole 6d has an inner diameter through which the rotating shaft 15 is slidably inserted.

A projection 6e for locking the locking piece 4a of the coil spring 4 to prevent rotation is provided on the input side end face of the mounting portion 6c.
Is formed. The projections 6e are provided one on each side of the locking piece 4a in the circumferential direction, and restrict the locking piece 4a in the circumferential direction so that the locking piece 4a does not rotate.

The cap 8 is a ring-shaped member, and has an outer diameter 8a that can be fitted into the opening 6b of the output member 6,
And an inner diameter 8b that can be slid on the outer peripheral surface.

The torque limiter 1 mounts the input member 2 on the mounting portion 6c of the output member 6, and connects the coil spring 4 to the input member 2.
And the locking piece 4a is inserted into the projection 6e of the output member 6.
And the cap 8 is connected to the opening 6 of the output member 6.
The coil spring 4 is fitted in the end portion of FIG. The torque limiter 1 is inserted into the rotating shaft 15 from the input member 2 side, and the paper return roller 13 is attached to the output member 6 side. The rotating shaft 15 is a shaft member having one end connected to the output shaft of the motor 12, and an engagement piece 15 a protruding perpendicular to the shaft at a predetermined position on the outer peripheral surface of the input member 2.
And inserted into the notch 2b of the input section. The paper return roller 13 has an engagement portion 13b on one side surface that can be engaged with the output portion 6a of the torque limiter 1, and inserts the rotation shaft into an insertion hole 13a that passes through the inside of the paper in the axial direction. 1 output member 6. Thus, the rotation torque of the motor 12 is input from the rotation shaft 15 to the torque limiter 1 and is output from the torque limiter 1 to the paper return roller 13.

The paper feed roller 14, which forms a pair with the paper return roller 13, is directly connected to a rotating shaft 16 that rotates in the paper feed direction.

Hereinafter, the operation of the torque limiter 1 will be described.

First, when transmitting rotational torque from the input member 2 to the output member 6 in a direction in which the coil spring 4 is tightened, the coil spring 4 is reduced in diameter by frictional force with the input member 2. By tightening the input member 2 more strongly, the rotational torque of the rotary shaft 15 is transmitted to the output member 6 and the paper feed roller 14 side.

Second, when the rotational torque is transmitted from the input member 2 to the output member 6 in a direction in which the coil spring 4 becomes more loose, the coil spring 4 is deformed by frictional force and expands in diameter. When a rotation torque equal to or greater than a certain rotation torque on the member 6 is applied, the coil spring 4 and the input member 2 relatively slide, and the output member 6 idles. For this reason, the torque limiter cannot transmit a certain amount of rotational torque in this direction.

With the above function of the torque limiter, the rotational torque transmitted to the paper return roller 13 can be limited. Therefore, as shown in FIG. 10A, when the paper is multi-fed, the paper return roller 13 rotates by receiving the rotation torque from the rotating shaft 15 and acts to return the paper 17a hitting the paper return roller 13 side. Then, the overlapping state of the multi-fed paper is eliminated. Further, as shown in FIG. 10B, when only one sheet of paper is fed in the sheet feeding device or when the sheet directly contacts the sheet feeding roller 14, the sheet returning roller 13 is used.
Idles and rotates in the sheet feeding direction by obtaining a rotational torque from the sheet feeding roller 14.

In a similar configuration, Japanese Patent Application Laid-Open No. 9-1
Japanese Patent Laid-Open No. 12568 discloses a bidirectional torque limiter, but the principle is the same as described above.

[0020]

As described above, the reason why the paper does not run idle when the paper is multi-fed is that the rotational torque that can be transmitted by the torque limiter 1 is determined by the coupling between the multi-fed paper and the paper. This is because it acts more than force.

That is, in order for the torque limiter to act to prevent double feeding of paper as described above, for example,
The paper return roller of the paper feeder must rotate in the paper return direction without idling when paper is multi-fed, and when the paper is normally fed one sheet, or when the paper return roller is fed. When the paper rollers are in direct contact, they need to idle and rotate in the paper feed direction.

For this reason, the torque limiter 1 used for the paper return roller is designed in consideration of a critical amount of rotational torque (hereinafter, referred to as "critical torque") that can be transmitted so as to satisfy the above-mentioned use conditions. . The "critical torque"
Is synonymous with the amount of rotational torque at which the torque limiter 1 starts idling (idling start torque).

The torque limiter 1 has a wire diameter of the coil spring 4, an inner diameter of the coil spring 4, a shaft diameter of the input member 2,
A critical torque that satisfies the above-mentioned use conditions is set using the coefficient of friction between the input member 2 and the coil spring 4 as a design condition.

However, in practice, the critical torque is associated with the amount of deformation of the coil spring 4 when receiving the rotational torque, and there is a difference in the amount of deformation of each coil spring 4. It is difficult to predict. In addition, in the manufacturing stage of the torque limiter, there is actually a slight variation for each product due to a dimensional error of each member and the like. Also,
A torque limiter used for a precision machine or the like requires a strict design for a critical torque. In such a case, if the critical torque of the torque limiter can be adjusted before and after manufacturing, an allowable error in the manufacturing stage can be increased.

Therefore, an object of the present invention is to provide a torque limiter capable of adjusting a critical torque.

[0026]

The amount of rotation torque transmitted by the torque limiter is due to the magnitude of the frictional force between the input member and the coil spring. As described above, the torque limiter idles between the input member and the input member when the torque limiter is deformed so as to expand in the vicinity of the locking end by receiving a rotational torque in a direction in which the fitting of the coil spring is loosened. This is because sliding occurs at

Therefore, the magnitude of the critical torque of the torque limiter is determined by the maximum friction force generated between the input member and the input member in a static state when the coil spring is deformed by receiving a rotational torque in a direction in which the coil spring is loosened. It is considered to be due to the size of

From the above considerations, the present inventors obtained a new idea that the critical torque of the torque limiter can be adjusted by regulating the amount of deformation of the coil spring.
The following torque limiter was invented.

That is, the torque limiter according to the present invention is configured such that an inner shaft member coaxially arranged, an outer shaft member housed in the outer periphery of the inner shaft member with a gap, and an outer peripheral surface of the inner shaft member are fitted. And a coil spring having one end locked to the outer shaft member, and capable of transmitting a rotational torque between the inner shaft member and the outer shaft member in a direction in which the coil spring is more tightly fitted, and In a torque limiter for transmitting a predetermined critical amount of rotational torque in a direction in which the fitting of the coil spring is loosened, a first portion for restricting a winding portion near a locking end of a coil spring in an inner diameter direction.
It is possible to adjust the critical amount of the rotational torque transmitted in the direction in which the fitting of the coil spring is loosened between the inner shaft member and the outer shaft member by providing a regulating portion.

Further, the torque limiter according to the present invention has an inner shaft member disposed coaxially with each other, an outer shaft member accommodated in the outer periphery of the inner shaft member with a gap, and an outer peripheral surface of the inner shaft member. And a coil limiter having both ends locked to the outer shaft member, and between the inner shaft member and the outer shaft member, a torque limiter that transmits a predetermined critical amount of rotation torque in either the left or right rotation direction. A first restricting portion for restricting a winding portion near one locking end of one end of the coil spring in the radial direction, and a second restricting portion for restricting a winding portion near the locking end of the other end of the coil spring in the radial direction.
A critical portion of the rotational torque transmitted between the inner shaft member and the outer shaft member can be adjusted in either of the left and right rotation directions.

Further, the torque limiter according to the present invention has an inner shaft member disposed coaxially with the outer shaft member, an outer shaft member housed in the outer periphery of the inner shaft member with a gap, and an inner circumferential surface of the outer shaft member. And a coil spring whose one end is locked to the inner shaft member, wherein a rotational torque can be transmitted between the inner shaft member and the outer shaft member in a direction in which the fitting of the coil spring is further tightened, and A torque limiter for transmitting a predetermined critical amount of rotational torque in a direction in which the spring fits more loosely includes a first restricting portion that restricts a winding portion in the vicinity of a locking end of a coil spring in an outer radial direction. It is possible to adjust the critical amount of the rotational torque transmitted in the direction in which the fitting of the coil spring is loosened between the shaft member and the outer shaft member.

Further, the torque limiter according to the present invention has an inner shaft member disposed coaxially with each other, an outer shaft member housed in the outer periphery of the inner shaft member with a gap, and fitted to an inner circumferential surface of the outer shaft member. And a coil spring having both ends locked to the inner shaft member, and transmitting a predetermined critical amount of rotational torque between the inner shaft member and the outer shaft member in either the left or right rotation direction. In the first and second aspects, a first restricting portion for restricting a winding portion near one locking end of one end of the coil spring in the outer diameter direction and a first restricting portion for restricting a winding portion near the locking end of the other end of the coil spring in the outer diameter direction. 2
A critical portion of the rotational torque transmitted between the inner shaft member and the outer shaft member can be adjusted in either of the left and right rotation directions.

In the above torque limiter, the critical torque may be adjusted by adjusting the position where the restricting portion is provided to be adjustable in the circumferential direction of the coil spring from the locking end, or by adjusting the position where the restricting portion is provided to the radius. One that can be adjusted in the direction and one in which the position where the regulating portion is provided can be adjusted in the circumferential direction and the radial direction of the coil spring from the locking end are considered.

[0034]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Various embodiments of a torque limiter according to the present invention will be described below with reference to the drawings. As shown in FIGS. 1 and 2, the torque limiter 20 according to the first embodiment of the present invention includes an input member 2 as an inner shaft member, a coil spring 4, and an output member 2 as an outer shaft member.
2. It has an adjuster ring 24 and a cap 8. The torque limiter 20 is disposed between the rotation shaft 15 driven to rotate by the motor 12 and the paper return roller 13.

The input member 2, the coil spring 4, the cap 8, the paper return roller 13, the rotating shaft 15, and the motor 12 among the above members are the same as the torque limiter 1 described above.
Since the member has the same configuration as that described in regard to the above, the same reference numerals are given and the duplicate description thereof will be omitted. The cap 8 has the same configuration as that described above, except that the cap 8 is attached to the input side opening of the adjuster ring 24.

The output member 22 is configured to rotate the shaft 1 in the axial direction.
Reference numeral 5 denotes a substantially cylindrical member having an insertable insertion hole 22a formed therein. The output side of the output member 22 is the paper return roller 1
3 is provided. An input side of the output member 22 is provided with a housing portion 22 capable of slidably housing the input member 2.
c. Also, on the input-side end face of the output member 22,
A projection 22d is provided for locking the locking piece 4a provided at the output end of the coil spring 4. The protrusions 22d are provided on both sides in the circumferential direction of the locking piece 4a, and restrain the locking piece 4a from rotating.

The adjuster ring 24 is a cylindrical member capable of accommodating the input member 2 and the coil spring 4 respectively. The adjuster ring 24 is fitted with the output member 6 so that it can be fitted into the output side opening. The cap 8 can be fitted so as to be fittable. As shown in FIG. 3, the adjuster ring 24 includes a restricting portion 24a protruding in a radial direction on an inner peripheral surface. Regulator 24a
Is set substantially equal to the difference between the inner diameter of the adjuster ring 24 and the outer diameter of the coil spring 4. The adjuster ring 24 can change its position in the circumferential direction relatively to the output member 22 in a state of being fitted to the output member 22.

The torque limiter 20 is assembled as follows. The coil spring 4 is fitted to the input member 2. With the locking piece 4a provided at the output end of the coil spring 4 sandwiched between the projections of the output member 22, the input member 2
Of the output member 22 is accommodated in the accommodating portion 22b of the output member 22. The adjuster ring 24 is inserted and fitted from the side of the input member 2 incorporated in the output member 22. The cap 8 is attached to the input side opening of the adjuster ring 24.
Here, the coil spring 4 is mounted on the input member 4 in a state where it is slightly compressed in the axial direction as compared with the natural state. The cap 8 regulates the coil spring 4 so as not to expand in the axial direction. This is to prevent the force for tightening the input member 2 from fluctuating due to the coil spring 4 deforming in the axial direction when receiving the rotational torque. Hereinafter, adjustment of the critical torque of the torque limiter 20 will be described.

As shown in FIG. 2, the torque limiter 2
Reference numeral 0 indicates that the regulating portion 24a provided in a protruding shape on the inner peripheral surface of the adjuster ring 24 comes into contact with the outer diameter side of the wound portion of the coil spring 4, and the coil spring 4 expands at the portion where the regulating portion 24a contacts. Regulate the diameter.

In the state where the regulating portion 24a is not provided, when the rotation torque is applied, the coil spring 4 expands and deforms by approximately one turn with the locking piece 4a restrained by the output member 22 as a base point. The restricting portion 24 a of the adjuster ring 24 restricts the amount of deformation of the contact portion of the coil spring 4.

As shown in FIG. 4, the angle q between the restricting portion 24a of the adjusting ring and the locking piece 4a of the coil spring 4 is formed.
FIG. 3 is a diagram showing a relationship between a critical torque (see FIG. 2) and a critical torque.

It should be noted that this relationship diagram shows that in the torque limiter 1, the input member 2 is made of SUS and the coil spring 4
Is a piano wire, the shaft diameter of the input member 2 is 11 mm, and the inner diameter of the coil spring 4 in the natural state is 1
The actual measurement was made with a wire diameter of 0.65 mm and a wire diameter of the coil spring 4 of 0.792 mm.

As shown in Table 1 below, the regulating portion 24a
Are set to 15 °, 30 °, 60 °, 90 °, 1
The critical torque was measured when the angle was changed in the order of 20 ° and 150 °. The idling start torque is such that the angle q is 15
In the case of °, it shows the largest value of 3.48 (N · cm), gradually decreases as the angle q increases, and the angle q
Is 90 °, the minimum value is 3.04 (N · cm), and then gradually increases again as the angle q increases to 120 ° and 150 °. The critical torque increases again as the angle q exceeds 150 ° and further increases, and gradually approaches a state equivalent to the case where no regulating member is provided.

By the above measurement, the adjusting ring 24
It can be understood that the critical torque fluctuates by changing the position of the regulating portion 24a in the circumferential direction.

That is, the torque limiter 20 rotates the adjuster ring 24 relative to the output member 22 so that the position of the restricting portion 24a of the adjuster ring 24 moves relative to the locking piece 4a of the coil spring 4. Adjust in the circumferential direction,
By regulating the amount of diameter expansion of the coil spring 4, the critical torque can be adjusted. For example, when it is desired to increase the critical torque within an adjustable range, the regulating unit 24a
May be brought closer to the locking piece 4a of the coil spring 4.
If it is desired to reduce the critical torque within an adjustable range, the position of the restricting portion 24a of the adjuster ring 24 may be set to be around 90 ° from the locking piece 4a of the coil spring 4.

Since this adjustment is based on a specific example of the torque limiter 20 that has obtained the above-described measured values, the angle q when the critical torque is minimized depends on the design conditions of the torque limiter 20 and the like. different.

In the torque limiter 20 according to the first embodiment, in the normal use state, almost no circumferential force is exerted on the adjuster ring 24, so that the relative circumferential direction of the adjuster ring 24 and the output member 22 is relatively small. It is not necessary to fix the positional relationship, but after adjusting the critical torque as described above, the adjuster ring 24 may be fixed to the output member 22 in order to surely maintain the state. Further, in order to easily adjust the critical torque, the angle at which the adjuster ring 24 can rotate in the circumferential direction with respect to the output member 22 may be intermittently set at a plurality of positions in advance.

Next, a description will be given of a torque limiter 21 according to a second embodiment of the present invention.

As shown in FIG. 5, the torque limiter 2
Reference numeral 1 denotes a screw which penetrates the adjuster ring 24 of the torque limiter 20 of the first embodiment radially through the adjuster ring 24 at a winding position corresponding to the vicinity of the locking piece 4a of the coil spring 4 instead of the restricting piece 24a. A member 24b is provided.

The adjustment of the critical torque of the torque limiter 21 is performed by adjusting the amount of protrusion of the screw member 24b provided on the adjuster ring 24 in the radial direction. That is,
Also in this case, the amount of deformation of the coil spring 4 can be adjusted, whereby the critical torque can be adjusted.

The position in the circumferential direction where the screw member 24b is provided is set at a position where the coil spring 4 expands most when the adjuster ring 24 is not provided with a restricting portion so that the adjustable width becomes larger. It is desirable to provide.

Further, the torque limiter 21 of the second embodiment
Then, since the diameter expansion amount of the coil spring 4 is adjusted in the radial direction by the screw member 4b, the adjuster ring 24 may be formed as a member integral with the output member 22. Further, the position where the screw member 24 b is provided may be adjusted in the circumferential direction along the winding direction of the coil spring 4 by the adjuster ring 24.

The torque limiter of the first embodiment and the second
Each of the torque limiters 21 according to the embodiments includes the output member 2
When the rotating shaft 15 of the motor 12 is connected to the rotating shaft 2 to input the rotating torque and output the rotating torque from the input member 2, it also functions as the torque limiter 21.
Also in this case, similarly to the above, the critical torque can be adjusted by the regulating portion 24a or the screw member 24b provided on the adjuster ring 24.

Next, a description will be given of a torque limiter 30 according to a third embodiment of the present invention.

As shown in FIG. 6, the torque limiter 3
Numeral 0 is provided on both sides of the coil spring 4 with a configuration for adjusting the critical torque of the torque limiter 21 of the second embodiment. That is, the second locking piece 4 is formed by bending the end of the coil spring 4 opposite to the locking piece 4a at right angles in the radial direction.
b, a projection 8c on the output side end face of the cap 8 for restricting the second locking piece 4b in the circumferential direction, and the adjuster ring 24 penetrates the adjuster ring 24 on the cap 8 side of the adjuster ring 24 in the radial direction. And a second screw member 24c for restricting the winding portion near 4b to the inner diameter side. The second locking piece 4b, the projection 8c, and the second screw member 24c correspond to the locking piece 4a, the projection 22d, and the screw member 24b, respectively.
Acts the same as. Although FIG. 6 illustrates the coil spring 4 with the number of turns being 1 for easy understanding, the coil spring 4 has a plurality of turns as shown by a broken line s in FIG.

When the input member 2 rotates clockwise, the winding portion of the coil spring 4 on the locking piece 4a side expands to allow the output member 22 to idle. If it rotates counterclockwise, the locking piece 4b of the coil spring
The winding portion on the side expands in diameter to allow the output member 22 to idle. That is, the torque limiter 30 is
Since both ends (4a, 4b) are locked to members on the output side, a structure is provided that acts as a torque limiter in both left and right rotation directions.

The torque limiter 30 adjusts the amount of protrusion of the screw member 24a from the adjuster ring 24, thereby adjusting the amount of diameter expansion of the coiled portion near the locking piece 4a side of the coil spring 4 and clockwise rotation. By adjusting the amount by which the screw member 24b protrudes from the adjuster ring 24, the diameter of the coil spring 4 in the vicinity of the locking piece 4b side can be increased. And the critical torque in the counterclockwise rotation direction can be adjusted. Thus, the torque limiter 30
Can adjust the critical torque in either rotational direction.

Next, a description will be given of a torque limiter 31 according to a fourth embodiment of the present invention.

As shown in FIG. 7, the torque limiter 3
Reference numeral 1 denotes an inner shaft member 32 and an outer shaft member 33 which are rotatably arranged coaxially with each other. The inner shaft member 32 is fitted on an inner peripheral surface 33 a of the outer shaft member 33, and an outer periphery of the inner shaft member 32. And a coil spring 34 whose one end 34a is locked to the projection 32a provided at the bottom. The inner shaft member 32 has a restricting portion 35 for restricting the winding portion near the locking end 34a of the coil spring 34 in the outer radial direction.
Is provided. The restricting portion 35 is constituted by a ring member 35 a slidably provided in the inner shaft member 32 in the circumferential direction, and adjusts the position of the restricting portion 35 in the circumferential direction along the winding portion of the coil spring 34. be able to. In this case, by adjusting the position of the regulating portion 35 in the circumferential direction, it is possible to adjust the magnitude of the critical amount (critical torque) of the rotational torque that can be transmitted between the inner shaft member 32 and the outer shaft member 33. it can. The torque limiter 31 can use the inner shaft member 32 as a rotation torque input member and the outer shaft member 33 as a rotation torque output member, and conversely, can use the outer shaft member 33 as a rotation torque input member. The inner shaft member 32 may be a member for outputting a rotational torque.

Further, in the torque limiter 31 of the fourth embodiment, as shown in FIG. 8, the protrusion member can be replaced with a member having a different protrusion amount as shown by a broken line in FIG. 36, the amount of protrusion of the protruding member 36 is changed to an appropriate amount, the amount of deformation of the coil spring 34 is regulated, and the critical amount of rotational torque that can be transmitted between the inner shaft member 32 and the outer shaft member 33 is controlled. The amount may be adjusted.

In the torque limiter according to the fourth embodiment, similarly to the torque limiter according to the third embodiment, a regulating member that regulates the amount of deformation at both ends of the coil spring 34 is provided, and the critical torque is applied to both directions. It may be a bidirectional torque limiter that can be adjusted.

The embodiment of the present invention has been described above, but the present invention is not limited to the above embodiment.

[0063]

[Table 1]

[0064]

The torque limiter according to the present invention has an inner shaft member disposed coaxially with the outer shaft member, an outer shaft member accommodated in the outer periphery of the inner shaft member with a gap, and an outer peripheral surface of the inner shaft member. And a coil spring having one end locked to the outer shaft member, and capable of transmitting a rotational torque between the inner shaft member and the outer shaft member in a direction in which the coil spring is more tightly fitted, and A torque limiter for transmitting a predetermined critical amount of rotational torque in a direction in which the fitting of the coil spring is loosened, since the first limiter for restricting the winding portion in the vicinity of the locking end of the coil spring in the radial direction is provided. Rotational torque transmitted in the direction in which the coil spring is more loosely fitted between the inner shaft member and the outer shaft member by regulating the amount of diameter expansion at the winding portion near the locking end of the coil spring by the regulating portion. Can be adjusted.

The torque limiter according to the present invention has an inner shaft member disposed coaxially with the outer shaft member, an outer shaft member accommodated in the outer periphery of the inner shaft member with a gap, and an outer peripheral surface of the inner shaft member. And a coil limiter having both ends locked to the outer shaft member, and transmitting a predetermined critical amount of rotation torque between the inner shaft member and the outer shaft member in either the left or right rotation direction. , A first restricting portion for restricting the winding portion near the locking end of one end of the coil spring in the radial direction, and a second restricting portion for restricting the winding portion near the locking end of the other end of the coil spring in the radial direction. The first restricting portion restricts the amount of diameter expansion at the winding portion near one locking end of one end of the coil spring, and the second restricting portion controls near the locking end of the other end of the coil spring. By regulating the amount of diameter expansion at the winding part of The critical amount of torque transmitted between the shaft member can also be adjusted to the left or right direction of rotation.

The torque limiter according to the present invention includes an inner shaft member disposed coaxially with the outer shaft member, an outer shaft member housed in the outer periphery of the inner shaft member with a gap, and a fitting to the inner circumferential surface of the outer shaft member. And a coil spring whose one end is locked to the inner shaft member, wherein a rotational torque can be transmitted between the inner shaft member and the outer shaft member in a direction in which the fitting of the coil spring is further tightened, and In a torque limiter that transmits a predetermined critical amount of rotational torque in a direction in which the spring fits more loosely, the torque limiter includes a first restricting portion that restricts a winding portion near a locking end of a coil spring in an outer radial direction. The first regulating portion regulates the amount of deformation at the winding portion near the locking end of the coil spring, so that the rotation is transmitted between the inner shaft member and the outer shaft member in a direction in which the fitting of the coil spring is loosened. The critical amount of torque can be adjusted.

The torque limiter according to the present invention includes an inner shaft member provided coaxially with the outer shaft member, an outer shaft member housed in the outer periphery of the inner shaft member with a gap, and an inner circumferential surface of the outer shaft member. And a coil spring whose both ends are locked to the inner shaft member, and transmits a predetermined critical amount of rotational torque between the inner shaft member and the outer shaft member in both left and right rotation directions. In the torque limiter, a first restricting portion that restricts a winding portion near an engagement end at one end of a coil spring in an outer diameter direction, and a first restriction portion that restricts a winding portion near an engagement end at another end of the coil spring in an outer diameter direction. The first regulating portion regulates the amount of deformation of the coil spring near the locking end at one end thereof, and the second regulating portion engages the other end of the coil spring. By regulating the amount of deformation at the winding part near the toe, the inner shaft part And the critical amount of torque transmitted between the outer shaft member, can be adjusted to the left or right direction of rotation.

In the above-described torque limiter, the adjustment of the critical torque may be performed, for example, by adjusting the position of the regulating portion to be movable in the circumferential direction of the coil spring from the locking end, or by adjusting the regulating portion. There are a type in which the provided position is adjustable in the radial direction, and a type in which the position of the regulating portion is adjustable in the circumferential direction and the radial direction of the coil spring from the locking end. These have a simple configuration for adjusting the amount of deformation of the coil spring and a simple adjustment method.

[Brief description of the drawings]

FIG. 1 is an axial sectional view of a torque limiter according to a first embodiment of the present invention.

FIG. 2 is an exploded perspective view of the torque limiter according to the first embodiment of the present invention.

FIG. 3 is a sectional view of the torque limiter according to the first embodiment of the present invention, taken along line AA in FIG. 1;

FIG. 4 is a diagram illustrating a relationship between an angle q at which a restricting portion of the torque limiter according to the first embodiment of the present invention is provided and a critical torque.

FIG. 5 is a radial cross-sectional view of a torque limiter according to a second embodiment of the present invention.

FIG. 6 is a radial cross-sectional view of a torque limiter according to a third embodiment of the present invention.

FIG. 7 is a sectional view in the radial direction of a torque limiter according to a fourth embodiment of the present invention.

FIG. 8 is a radial cross-sectional view of a torque limiter according to a fourth embodiment of the present invention.

FIG. 9 is a diagram illustrating a use state of a torque limiter in the sheet feeding device.

FIG. 10A is a diagram illustrating a state in which paper is multi-fed in a paper feeding device. FIG. 3B is a diagram illustrating a state in which only one sheet has been fed in the sheet feeding device.

FIG. 11 is an axial sectional view of the torque limiter.

[Explanation of symbols]

 2 Input member 4 Coil spring 4a, 4b Locking piece 8 Cap 12 Motor 13 Paper return roller 15 Rotary shaft 22 Output member 24 Adjuster ring 24a Restrictor 24b, 24c Screw member

Claims (7)

[Claims] An inner shaft member disposed coaxially with the outer shaft member; an outer shaft member housed in the outer periphery of the inner shaft member with a gap therebetween; and an outer shaft member fitted to an outer peripheral surface of the inner shaft member. A coil spring having one end locked to the inner shaft member and the outer shaft member, capable of transmitting a rotational torque in a direction in which the fitting of the coil spring is tightened, and a fitting of the coil spring. A torque limiter for transmitting a predetermined critical amount of rotational torque in a direction in which the attachment is loosened, further comprising a first restricting portion for restricting a winding portion in the vicinity of a locking end of the coil spring in an inner diameter direction; A torque limiter capable of adjusting a critical amount of rotational torque transmitted in a direction in which the fitting of the coil spring is loosened between the shaft member and the outer shaft member. 2. An inner shaft member disposed coaxially with each other, an outer shaft member housed in the outer periphery of the inner shaft member with a gap therebetween, and an outer shaft member fitted on the outer peripheral surface of the inner shaft member. A torque limiter for transmitting a predetermined critical amount of rotation torque between the inner shaft member and the outer shaft member in either the left or right rotation direction. A first restricting portion for restricting the winding portion near the locking end at one end in the radial direction and a second restricting portion for restricting the winding portion near the locking end at the other end of the coil spring in the radial direction. A torque limiter, wherein a critical amount of the rotational torque transmitted between the inner shaft member and the outer shaft member can be adjusted in either the left or right rotation direction. 3. An inner shaft member disposed coaxially with each other, an outer shaft member housed in the outer periphery of the inner shaft member with a gap, and an inner shaft fitted to an inner peripheral surface of the outer shaft member, A coil spring having one end locked to the member, between the inner shaft member and the outer shaft member, capable of transmitting a rotational torque in a direction in which the fitting of the coil spring is tightened, and A torque limiter for transmitting a predetermined critical amount of rotational torque in a direction in which the fitting is loosened, further comprising: a first restricting portion for restricting a winding portion near a locking end of the coil spring in an outer radial direction; A torque limiter capable of adjusting a critical amount of rotational torque transmitted between a shaft member and an outer shaft member in a direction in which the fitting of the coil spring is loosened. 4. An inner shaft member disposed coaxially with each other, an outer shaft member accommodated in the outer periphery of the inner shaft member with a gap, and an inner shaft fitted to an inner peripheral surface of the outer shaft member, and A coil spring having both ends locked to a member, wherein the torque limiter transmits a predetermined critical amount of rotational torque between the inner shaft member and the outer shaft member in either the left or right rotation direction. A first restricting portion for restricting the winding portion near the locking end of one end of the spring in the outer diameter direction, and a second restricting portion for restricting the winding portion near the locking end of the other end of the coil spring in the outer diameter direction. A critical amount of rotational torque transmitted between the inner shaft member and the outer shaft member can be adjusted in either the left or right rotation direction. 5. The torque limiter according to claim 1, wherein a position at which the regulating portion is provided is adjustable from the locking end in a circumferential direction of the coil spring. 6. The torque limiter according to claim 1, wherein a position at which the regulating portion is provided is adjustable in a radial direction. 7. The torque limiter according to claim 1, wherein a position at which the regulating portion is provided is adjustable in a circumferential direction and a radial direction of the coil spring from the locking end.