JP2003028190A - Torque limiter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To function as a torque limiter in both rotating directions, and to enable a torque value to be adjusted. SOLUTION: This torque limiter is formed of an outer member 1, an inner ring 3 housed in the outer member 1 and supported by an end wall member 2 freely to rotate, a torque generating elastic member 4 installed in the outer diameter surface of the inner ring 3 with a required tensile force, and a cover member 5 for sealing between the inner ring 3 and the outer member 3 at an end opposite to the end wall. A first adjusting spring 21 and a second adjusting spring 22 are formed, and a free end of the first adjusting spring 21 is engaged with the cover member 5, and a free end of the second adjusting spring 22 is engaged with the outer member 1, and the cover member 5 and the outer member 1 are rotated opposite to each other to shrink or enlarge the diameter of each adjusting spring 21 and 22 to adjust the torque.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bidirectional torque limiter used in copying machines and printers.

[0002]

2. Description of the Related Art A torque limiter is used for a torque transmitting portion in a rotating portion of a copying machine or a printer, and a required torque value and a rotation direction of generated torque are different depending on a model and a function in which the torque limiter is used. . In some cases, a bidirectional torque limiter is required for the paper separating section to provide a paper jam clearing function.

FIG. 14 shows a torque limiter with adjustable torque. In this torque limiter, one end of an inner ring 52 inserted coaxially inside a cylindrical outer member 51 is fitted and supported by an inner surface of an end wall 53 of the outer member 51 so as to be relatively rotatable. Between the outer member 51 and the inner ring 52, the coil spring 54 is fitted to the outer diameter surface of the inner ring 52, and the lid member 55 is fitted to the open ends of the outer member 51 and the inner ring 52. The tip of the inner ring 52 penetrates the lid member 55 and is exposed to the outside. The coil spring 54 has a small-diameter torque generating portion 54a tightly bound to the inner ring 52 and a larger-diameter torque adjusting portion 54b. The hook 56 protruding from the end on the torque generating portion 54a side has the above-mentioned end. The hook 57 that is engaged with the wall 53 and that protrudes from the end portion on the torque adjusting portion 54b side is engaged with the lid member 55.

The torque limiter having the above structure is a one-way torque limiter that transmits torque only in one direction determined by the winding direction of the coil spring 54 and cannot transmit torque in the opposite direction due to winding around the inner ring 52. The torque value is determined by the binding force of the torque generating portion 54a of the coil spring 54 to the inner ring 52. The torque value is adjusted by rotating the lid member 55 from the outside and changing the binding force of the torque generating portion 54a through the torque adjusting portion 54b.

The torque limiter shown in FIGS. 15 and 16 is a patent application of the applicant (Japanese Patent Application No. 2001-447).
97), a cylindrical spring 59 having a slit 58 is used in place of the coil spring 54, and the cylindrical spring 59 is fitted to the outer diameter surface of the inner ring 52 with a predetermined binding force to form a recess at one end thereof. 60 is engaged with the convex portion 61 of the end wall 53 of the external member 51. Since the binding force of the cylindrical spring 59 has no direction, torque can be transmitted in both directions.

[0006]

As described above, the torque limiter using the coil spring 54 can adjust the torque value, but cannot transmit the torque in both directions. For this reason, it is necessary to manufacture two types of torque limiters, one for right rotation and the other for left rotation, and use them according to the rotation direction. If two types of torque limiters are required, it is necessary to use two types of torque limiters together. there were.

The torque limiter using the cylindrical spring 59 can transmit torque in both directions, but the torque value cannot be adjusted. Therefore, when a large torque needs to be generated, the spring 59 is tightly bound to the inner ring 52. It is necessary to strengthen it and assemble it. Therefore, the spring 59 and the inner ring 52
There was a problem that the assembly work of was difficult. In addition, there have been inconveniences such as the need to manage many springs of different sizes and parts of the inner ring for adjusting the fit.

Therefore, it is an object of the present invention to provide a torque limiter which is bidirectional and whose torque value can be adjusted.

[0009]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a tubular outer member, an inner ring housed in the outer member and rotatably supported by an end wall thereof, and an inner ring thereof. A resilient member for torque generation, which is mounted on the outer diameter surface of the member with a required binding force, and a lid member that closes between the inner ring and the outer member at the end opposite to the end wall. In a torque limiter configured to prevent a co-rotation of the elastic member and the inner ring by engaging a part of the inner wall with the end wall, and generate a torque of a predetermined magnitude by friction between the elastic member and the inner ring. , The end wall is formed by an end wall member forcibly fitted to an external member, and the elastic member is provided with a cylindrical spring body having a slit in the axial direction, and one side edge of the slit to the other side edge. The first adjustment of the mainspring shape wound beyond And a spring-shaped second adjusting spring wound from the other side edge over one side edge, and the free end of the first adjusting spring is attached to the lid member. The constitution was adopted in which the free ends of the preparation springs of No. 2 were engaged with the external members respectively.

According to the above construction, since the cylindrical spring body having the slit is fitted to the outer diameter surface of the inner ring with a required binding force, the same torque can be applied to the inner ring rotating in either the left or right direction. And functions as a bidirectional torque limiter. Further, when the lid member and the outer member are relatively rotated in the reverse direction with the end wall member fixed, the first and second adjusting springs bend in the diameter reducing or expanding direction. As a result, the binding force of the spring body changes, so that the torque value can be adjusted. Further, since both adjusting springs are evenly bent, the same torque can be generated even if the inner ring rotates in either the left or right direction.

A third spiral spring type adjusting spring wound around the spring body in the same direction as the first adjusting spring is provided at an intermediate position between the first and second adjusting springs. A configuration in which the free end of the adjusting spring is engaged with the lid member can be adopted. According to this configuration, the combined spring force of the first and second adjusting springs and the spring force of the third adjusting spring alone are made different from each other, whereby the torque value can be changed according to the rotation direction.

As another solution, a cylindrical outer member, an inner ring housed in the outer member and rotatably supported by an end wall of the outer ring, and mounted on the outer surface of the inner ring with a required binding force. And a lid member that closes between the inner ring and the outer member at the end opposite to the end wall, and engages a part of the elastic member with the end wall. In this torque limiter, the end wall is forcibly fitted to the outer member in a torque limiter that prevents co-rotation of the elastic member and the inner ring and generates a torque of a predetermined magnitude due to friction between the elastic member and the inner ring. A spring body having a slit in the axial direction, and a spring-shaped adjusting spring wound from one side edge of the slit to the other side edge. Have first
Of the adjusting spring of the first elastic body and a second elastic body having a spring-shaped adjusting spring wound from the other side edge over one side edge. It is possible to employ a configuration in which the free end portion is engaged with the lid member and the free end portion of the second elastic body adjusting spring is engaged with the external member. This structure is easy to manufacture because the elastic member is separated into two members.

In any of the above constructions, a tubular base spring having a slit in the axial direction is interposed between the outer diameter surface of the inner ring and the spring body by fitting the inner ring with a predetermined binding force. A configuration can be adopted. According to this configuration,
It is possible to obtain a torque value as large as the binding force of the base spring.

By adopting a structure in which one or both of the spring body of the elastic member and the spiral spring adjusting spring are provided with a lightening portion, the weight of the elastic member can be reduced.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings. The first embodiment shown in FIGS. 1 to 3 includes a cylindrical outer member 1, an end wall member 2 press-fitted into one end of the outer member 1, and an end wall member housed inside the outer member 1. 2, an inner ring 3 rotatably supported in a concentric state, an elastic member 4 for torque generation mounted on the outer diameter surface of the inner ring 3 with a required binding force, and a block between the outer member 1 and the inner ring 3. And a lid member 5 that operates.

As shown in FIG. 2A, the outer member 1 is provided with grooves 6 and 7 at both ends of its inner diameter surface, and the end wall member 2 is forcibly fitted to the groove 6 side. . Further, the lid member 5 is forcibly fitted to the groove 7 side. In addition, on the end wall member 2 side of the external member 1, an outer periphery of the end portion is provided with a concave and convex portion 8 for hooking a tool at the time of torque adjustment, and an engagement hole 9 for engaging an adjustment spring described later.

The end wall member 2 is provided with a rib 10 fitted in the groove 6 of the external member 1 on the outer diameter surface thereof, and a shaft hole 11 is provided at the center thereof. Around the shaft hole 11, a fitting portion 12 is provided on the inner surface side and a pair of protrusions 13, 13 is provided on the outer surface side, and a recess 14 (see FIG. 1) is provided on the peripheral wall of the fitting portion 12. As described above, the end wall member 2 is forcibly fitted into the groove 6 of the outer member 1 via the rib 10. As will be described later, the friction caused by the fitting is such that when external force is applied during torque adjustment, the external member 1 and the end wall member 2
Rotate relative to each other, but they are set to a size such that they do not rotate relative to each other during normal torque transmission.

The center portion of the inner ring 3 serves as a sliding contact surface 15 having a larger diameter, and a small diameter portion at one end thereof is rotatably fitted to the fitting portion 12 and a small diameter portion at the other end. Penetrates the lid member 5 and projects to the outside. Engaging recesses 16 and 16 are provided in the protruding portions, and the engaging recesses 16 and 16 are provided.
The pin 18 of the shaft 17, which is inserted through the inner diameter surface of the inner ring 3, is engaged with.

The elastic member 4 is formed by using an elastic metal plate, and as shown in FIG. 3 (a), a rectangular spring main body 19 and band-shaped first and second adjusting springs in a developed state. Two
1 and 22, a first adjusting spring 21 having a width slightly less than half the length is provided on one side of the spring main body 19 at one end, and the other side has a similar width. The second adjusting spring 22 is provided so as to be offset to the other end. Spring body 19
Is a cylindrical body having a slit 23 in the axial direction, which is wound and bent so that both sides on which the adjusting springs 21 and 22 are provided are close to each other.

As shown in FIG. 3 (b), the first adjusting spring 21 extends from one side edge of the slit 23 to the other side edge, and winds about one turn and a quarter turn. It is formed in a shape, and the bending engagement portion 24 that is bent outward is formed at the free end thereof. On the contrary, the second adjusting spring 22 is wound from the other side edge of the slit 23 to the one side edge, and is similarly wound about one round and a quarter turn to form a spiral spring. Bending engagement portion 2 bent outward at the free end
5 is formed. Each bending engagement portion 24 and 25 is
As shown in FIGS. 1 and 2 (b), they are on one diameter.
Further, the engagement protrusion 26 is formed at one end of the spring body 19 (the end on the second adjustment spring 22 side).

The elastic member 4 is fitted into the sliding contact portion 15 of the inner ring 3 by slightly expanding the diameter of the spring body 19 thereof, and is supported on the outer diameter surface thereof by a required binding force to form a spring convex portion. 26 is engaged in the recess 14 of the end wall member 2.

The lid member 5 comprises an annular lid portion 27 and a cylindrical portion 28 integrally provided on the inner end surface of the lid portion 27. The outer diameter surface of the lid portion 27 is provided with the groove 6 of the outer member 1. Ribs 29 to be fitted are provided. In addition, a slit 31 opened at its tip is provided at one location of the tubular portion 28, and a tool engagement hole 32 is provided at the outer end surface.

The lid member 5 is forcibly fitted with the rib 29 in the groove 7 of the outer member 1 as described above. As will be described later, the friction caused by the forced fitting is such that the lid member 5 and the outer member 1 rotate relative to each other when a force is applied from the outside during torque adjustment, but the relative rotation does not occur during normal torque transmission. Is set to.

The engaging portion 24 of the elastic member 4 is inserted and engaged with the slit 31 of the lid member 5, and the other opposing engaging portion 25 is engaged with the engaging hole 9 of the external member 1 described above. (See FIG. 2B). As described above, the shaft 17 is inserted into the shaft hole 33 of the lid 27.

The torque limiter of the first embodiment is as described above, and its operation will be described below. In both cases, the rotational torque applied to the shaft 17 in both the left and right directions is from the inner ring 3 to the spring body 19 of the elastic member 4, the adjustment spring 21,
22 is transmitted to the external member 1 and the end wall member 2 and is transmitted to another member engaged with the projections 13 of the end wall member 2, and the load applied to the member exceeds a certain torque value. In this case, a slip occurs between the sliding contact surface 15 of the inner ring 3 and the spring body 19 to interrupt the torque transmission. This acts as a bidirectional torque limiter.

In the case of adjusting the above torque value, the end wall member 2 is fixed, and the concave and convex portions 8 of the outer member 1 and the engaging holes 32 of the lid member 5 are respectively fitted with tools so as to be in the opposite directions. Rotate to. Then, the diameters of the first and second adjusting springs 21 and 22 are simultaneously reduced or expanded in accordance with the rotation direction, and when the diameters are reduced, the friction of the spring body 19 with respect to the sliding contact surface 15 increases and the torque value. Goes up. On the contrary,
If the diameter is increased, the torque value will decrease.

At the time of adjusting the torque value, the first and second adjusting springs 21 and 22 are moved in the radial direction or the radial direction by the relative reverse rotation of the outer member 1 and the lid member 5. Even in this case, the springs 19 are bent equally, so that the torque is uniformly adjusted over the entire length of the spring body 19.

Next, the second embodiment shown in FIGS. 4 and 5 is basically the same as the first embodiment described above.
The only difference is that an auxiliary spring 34 is added to the structure. That is, the auxiliary spring 34 is formed by winding a metal plate similar to that of the elastic member 4 described above and forming it into a cylindrical shape having a slit 35 in the axial direction.
6 is provided.

The auxiliary spring 34 is attached to the sliding contact surface 15 of the inner ring 3.
The fitting convex portion 36 is engaged with the concave portion 14 of the end wall member 2 while being fitted to the outer diameter surface of the end portion with a predetermined binding force. On the outer diameter surface of the auxiliary spring 34, the spring body 1 of the elastic member 4 described above is attached.
9 is fitted. As a result, as compared with the case of the above-described first embodiment, the entire binding force is increased by the binding force of the auxiliary spring 34 in both the left and right rotation directions, and a large torque value can be obtained. The torque value can be adjusted by the amount of change in the spring force of the second adjusting springs 21 and 22. Since other configurations are the same as those of the first embodiment described above, the same parts are denoted by the same reference numerals and the description thereof will be omitted.

Next, the third embodiment shown in FIGS. 6 to 8 is different from the first embodiment described above mainly in the structure of the elastic member 4. That is, the elastic member 4 in this case has the third adjustment spring 37 in addition to the spring body 19 and the first and second adjustment springs 21 and 22 described above. The third adjusting spring 37 is provided outside the second adjusting spring 22, and has a shape in which the second adjusting spring 22 is located in the middle and is sandwiched between the first and third adjusting springs. The third adjusting spring 37 is wound in the same direction as the first adjusting spring 21, and a bending engaging portion 38 bent outward is provided at its free end (see FIG. 7A).

In this case, the lid member 5 is provided with two parallel arms 39, 39 on the inner surface side of the annular lid portion 27, and a slit 41 is provided between the arms 39, 39. The bending engaging portions 24 and 38 of the first and third adjusting springs of the elastic member 4 are inserted into and engaged with the slit 41. The engaging projection 25 of the second adjusting spring 22 is engaged with the engaging hole 9 of the external member 1 as described above.

The adjusting springs 21 and 2 of the elastic member 4 described above.
If 2, 37 are formed to have the same width, the spring force of the first and third adjusting springs 21, 37 wound in the same direction is twice the spring force of the second adjusting spring. The torque value is also doubled. Therefore, a bidirectional torque limiter having different torque values depending on the rotation direction can be obtained. Further, in order to adjust the torque value, the lid member 5 and the external member 1
When and are reversely rotated in the above-described manner, the first and third adjusting springs 21 and 37 rotate in the same direction, and the second adjusting spring 22 rotates in the opposite direction, so that the diameter is reduced or expanded, respectively. Change the torque value.

Next, the fourth embodiment shown in FIGS. 9 and 10 has a structure in which an auxiliary spring 34 is added to the structure of the third embodiment. This auxiliary spring 34 is the same as in the case of the above-described second embodiment (see FIGS. 4 and 5), and is fitted to the outer diameter surface of the sliding contact surface 15 with a predetermined binding force, and its engagement The same applies to engaging the fitting convex portion 36 with the concave portion 14 of the end wall member 2 and fitting the spring main body 19 of the elastic member 4 to the outer diameter surface of the auxiliary spring 34 thereof. As a result, as compared with the case of the above-described third embodiment, the overall binding force increases by the binding force of the auxiliary spring 34 in either the left or right rotation direction, and thus a large torque value can be obtained, and the first to the first The torque value can be adjusted by the amount of change in the spring force of the adjusting springs 21, 22, 37 of No. 3.

In the fifth embodiment shown in FIGS. 11 and 12, the elastic member 4 is divided into two parts in the axial direction and is constituted by a first elastic member 4a and a second elastic member 4b. Only the difference from the case of the first embodiment described above, and other configurations are the same. That is, the first elastic member 4 in this case
a and the second elastic member 4b have slits 23 in the axial direction.
tubular spring bodies 19a, 19b having a, 23b,
A first spiral spring wound from the side edges on the opposite sides of the slits 23a, 23b to the other side edges.
Adjustment spring 21 and second adjustment spring 22. Bending engagement portions 24 and 25 are provided at the tips of the adjustment springs 21 and 22, respectively. In addition, the spring body 19b of the above-mentioned spring body 19a
The engaging convex portion 26a is provided on the side edge on the side, and the engaging concave portion 26b is provided on the side of the spring main body 19b facing the engaging convex portion 26a.
The engaging convex portion 26a and the engaging concave portion 26b are axially engaged with each other and integrated in the rotational direction. The engagement protrusion 26 is provided on the opposite side of the spring body 19b, and the engagement protrusion 26 is engaged with the recess 14 of the end wall member 2 as in the case described above. The bent engaging portions 24 and 25 are engaged with the slit 31 of the lid member 5 and the engaging hole 9 of the external member 1, respectively.

In the torque limiter of the fifth embodiment having the above structure, the elastic body 4 is the first and second elastic bodies 4a and 4b.
However, since they are engaged with each other by the engaging projections 26a and the engaging recesses 26b, the action as the torque limiter is the same as that of the first embodiment.
However, by separating the elastic body 4 into two members in this way, there is an advantage that the elastic bodies 4a and 4b can be easily manufactured.

Next, a sixth embodiment shown in FIG. 12 is obtained by adding an auxiliary spring 34 to the structure of the fifth embodiment. Since the relationship is similar to the relationship between the second embodiment with respect to the first embodiment and the fourth embodiment with respect to the third embodiment, the description thereof will be omitted.

FIG. 13 shows that in the elastic body 4 in each of the embodiments, weight reduction can be achieved by providing the spring-shaped adjusting springs 21 and 22 with the lightening portions 42 and 42 by the elongated holes. .

[0038]

According to the present invention, there are the following effects. (1) Since the torque limiter of the present invention can adjust the torque, the elastic member and the inner ring can be loosely fitted at the time of assembly, and the torque can be set to a necessary torque value after the assembly. It has the advantage of being easy to assemble. (2) If the torque limiter cannot adjust the torque,
In order to meet various torque requirements, it is necessary to manage many springs with different dimensions and parts of the inner ring for adjusting fitting, but in the case of the torque limiter of the present invention that can adjust torque, parts management is required. There is an advantage of being less. (3) Since the torque limiter of the present invention can generate the same torque by rotating in both directions, it is not necessary to manage the parts due to the difference in rotation direction and the parts for each generated torque value in manufacturing the torque limiter. In the use of the torque limiter, it is not necessary to manage the torque limiter due to the difference in the rotation direction, and it is possible to use the torque limiter in a portion where the bidirectional rotation torque limiter is required.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a first embodiment.

FIG. 2 (a) is a sectional view of the same as-assembled state. (B) Sectional drawing in the bb line of (a) figure

FIG. 3A is a partially omitted development view of the elastic body of the above. (B) Partially omitted perspective view of the above elastic body

FIG. 4 is an exploded perspective view of the second embodiment.

FIG. 5 (a) is a sectional view of the same as the assembled state. (B) Sectional drawing in the bb line of (a) figure

FIG. 6 is an exploded perspective view of a third embodiment.

FIG. 7 (a) is a sectional view of the same as the assembled state. (B) Sectional drawing in the bb line of (a) figure

FIG. 8A is a partially omitted development view of the above elastic body. (B) Partially omitted perspective view of the above elastic body

FIG. 9 is an exploded perspective view of a fourth embodiment.

FIG. 10 (a) is a sectional view of the same as the assembled state. (B) Sectional drawing in the bb line of (a) figure

FIG. 11 is an exploded perspective view of a fifth embodiment.

FIG. 12 is an exploded perspective view of a sixth embodiment.

FIG. 13 is a perspective view showing a modified example of the elastic body.

FIG. 14 is a sectional view of a conventional example.

FIG. 15 is an exploded perspective view of another conventional example.

FIG. 16 (a) is a sectional view of the same as the assembled state. (B) Sectional drawing in the bb line of (a) figure

[Explanation of symbols]

1 External member 2 End wall member 3 inner ring 4 Elastic member 5 Lid member 6 grooves 7 groove 8 uneven parts 9 engagement holes 10 ribs 11 shaft hole 12 Fitting part 13 Protrusion 14 recess 15 Sliding surface 16 Engagement recess 17 axes 18 pin 19 Spring body 21 First Adjustment Spring 22 Second adjusting spring 23 slits 24 Bending engagement part 25 Bending engagement part 26 Engagement protrusion 27 Lid 28 Tube 29 ribs 31 slits 32 engagement hole 33 shaft hole 34 Auxiliary spring 35 slits 36 Engagement protrusion 37 Third Adjustment Spring 38 Bending engagement part 39 arms 41 slits 42 meat removal section

Claims (5)

[Claims] 1. An outer member, an inner ring housed in the outer member and rotatably supported by an end wall thereof, and an elastic member for torque generation mounted on the outer diameter surface of the inner ring with a required binding force. A cover member that closes the space between the inner ring and the outer member at the end opposite to the end wall, and the elastic member and the inner ring are formed by engaging a part of the elastic member with the end wall. In a torque limiter that prevents co-rotation and generates a torque of a predetermined magnitude by friction between the elastic member and the inner ring, the end wall is formed by an end wall member that is forcibly fitted to an external member, The elastic member is a tubular spring body having a slit in the axial direction, a spring-shaped first adjusting spring wound from one side edge of the slit over the other side edge, and conversely the other side. A mainspring wound from one side edge over one side edge A second adjusting spring having a shape, wherein the free end of the first adjusting spring is engaged with the lid member and the free end of the second adjusting spring is engaged with the outer member. A torque limiter. 2. A third mainspring type adjusting spring wound around the spring body in the same direction as the first adjusting spring, wherein the second adjusting spring is attached to the second adjusting spring.
2. The torque limiter according to claim 1, wherein the adjusting spring is provided on both sides of the adjusting spring, and the free end portion of the third adjusting spring is engaged with the lid member. 3. A tubular outer member, an inner ring housed in the outer member and rotatably supported on an end wall of the outer ring, and a torque generating member mounted on the outer diameter surface of the inner ring with a required binding force. An elastic member and a lid member that closes the space between the inner ring and the outer member at the end opposite to the end wall, and the elastic member is formed by engaging a part of the elastic member with the end wall. In a torque limiter that prevents co-rotation with the inner ring and generates a torque of a predetermined magnitude by friction between the elastic member and the inner ring, the end wall is forcibly fitted to the outer member by an end wall member. A first elastic body formed by forming the elastic member into a cylindrical spring body having a slit in the axial direction, and a spiral spring adjusting spring wound from one side edge of the slit to the other side edge. On the contrary, cross over one side edge from the other side edge above. And a second elastic body having a spiral spring adjusting spring, and the free end of the adjusting spring of the first elastic body is attached to the lid member and the adjusting spring of the second elastic body is free. A torque limiter, characterized in that its ends are engaged with the external member, respectively. 4. A tubular auxiliary spring having a slit in the axial direction is fitted between the outer diameter surface of the inner ring and the spring body by a predetermined binding force and is interposed therebetween. The torque limiter according to any one of claims 1 to 3. 5. The torque limiter according to claim 1, wherein one or both of the spring body of the elastic member and the adjusting spring of the spiral spring is provided with a lightening portion. .