WO2020195224A1

WO2020195224A1 - Torque limiter provided with coupling member

Info

Publication number: WO2020195224A1
Application number: PCT/JP2020/004737
Authority: WO
Inventors: 太郎磯部
Original assignee: 株式会社オリジン
Priority date: 2019-03-22
Filing date: 2020-02-07
Publication date: 2020-10-01
Also published as: JP6802310B2; JP2020153484A; CN113597519A

Abstract

Provided is a novel torque limiter with which a metal inner member (2) can be connected to any external device without changing the shape of the inner member (2). A coupling member (42) made of a synthetic resin is detachably linked to the inner member (2), and the inner member (2) is connected to an external device via the coupling member (42).

Description

Torque limiter with fittings

The present invention includes a relatively rotatable inner member and outer member, and a coil spring mounted between them, and the rotational torque for relatively rotating the inner member and the outer member is larger than a predetermined value. It relates to a torque limiter in which the outer member and the inner member rotate relative to each other by overcoming the frictional force of the coil spring.

In printers and copiers, a paper feed device is used to feed paper one by one from a group of paper stacked in the vertical direction. In such a paper feeding device, the paper is taken out from the paper group in a multi-layered state in which a plurality of papers are adsorbed vertically by a minute mutual adsorption force such as static electricity, and the paper is in the multi-layered state in a printer or a copying machine. In order to avoid the possibility that the paper is fed to the main body, the paper feed device is usually equipped with a torque limiter. The torque limiter is not limited to the paper feeding device, but is also used as a component that protects the motor by disconnecting the load when an overload is applied to the motor or the like of the drive source.

For example, in Patent Document 1 below, a metal inner member, a coil spring mounted in contact with the outer peripheral surface of the inner member and formed by winding a wire rod, and the inner side to which the coil spring is mounted. A tubular outer member into which the member is inserted is provided, the inner member and the outer member have a common central axis, and the coil spring is engaged with the outer member so as not to rotate relative to the outer member. When a rotational torque around the central axis that relatively rotates the inner member and the outer member is applied, friction between the inner member and the outer member when the rotational torque is larger than a predetermined value. A torque limiter is disclosed in which the outer member and the inner member rotate relative to each other by overcoming a force.

Japanese Patent No. 6355596

The torque limiter is a functional component that is incorporated and used in various devices, and since the inner member is connected to various external devices depending on the device to be incorporated, the external member in the inner member depends on the connected external device. It is necessary to change the shape of the connection part with the device as appropriate. When the inner member is made of metal, it takes more time to manufacture than when it is made of synthetic resin, so that it costs a lot to change the shape of the connecting portion each time. Further, if there are a large number of torque limiters having the same function but different only in the connection portion, it becomes difficult to manage and store the torque limiter as a product.

Further, when the inner member is manufactured from a plate-shaped metal by press molding, the inner ring member has a recessed shape as a whole, so that the connecting portion formed at the axial end is inevitably notched. Therefore, the means for connecting the external device and the inner member is limited.

The present invention has been made in view of the above facts, and its main technical problem is that the inner member can be connected to any external device without changing the shape of the metal inner member. It is to provide a torque limiter.

As a result of diligent studies, the present inventor has made the joint member made of synthetic resin detachably connected to the inner member, and the inner member is connected to an external device via the joint member. We found that we could achieve the task.

That is, according to the present invention, as a torque limiter that achieves the main technical problem, a metal inner member and a coil spring that is mounted in contact with the outer peripheral surface of the inner member and is formed by winding a wire rod And a tubular outer member into which the inner member to which the coil spring is mounted is inserted.
The inner member and the outer member have a common central axis, and the coil spring is engaged with the outer member so as not to rotate relative to each other.
When a rotational torque around the central axis that relatively rotates the inner member and the outer member is applied, when the rotational torque is larger than a predetermined value, between the inner member and the outer member. In a torque limiter in which the outer member and the inner member rotate relative to each other by overcoming the frictional force.
Provided is a torque limiter characterized in that a joint member made of synthetic resin is detachably connected to the inner member, and the inner member is connected to an external device via the joint member.

Preferably, the inner member and the joint member are connected by a notch having an open axial end and a protrusion protruding in the axial direction. In this case, a positioning small protrusion that further protrudes in the axial direction is locally attached to the protruding end surface of the protrusion, and the positioning is performed prior to the protrusion being inserted into the notch. The small protrusion should be inserted into the notch. The joint member is provided with an annular flange coaxially with the common central axis, and protrusions protruding inward in the radial direction are axially spaced on the inner peripheral surface of the outer member. When the joint member and the outer member are combined, it is preferable that the flange is sandwiched by the two protrusions. Preferably, the inner member and the outer member are provided with fitting means having a circular cross section that fits each other on the common central axis. It is preferable that the inner member has a tubular shape whose diameter decreases from one end in the axial direction toward the other end. The inner member is preferably manufactured from a plate-shaped metal by press molding.

In the torque limiter of the present invention, a joint member made of synthetic resin is detachably connected to the inner member, and the inner member is connected to an external device via the joint member. Therefore, if a plurality of joint members are prepared in advance according to the external device to be connected, the main configuration of the torque limiter can be maintained and only the joint member can be replaced with an appropriate one to connect to each external device. This makes it possible to reduce the manufacturing cost and facilitate the management and storage of the torque limiter as a product. In particular, since the joint member of the present invention is made of synthetic resin, it can be easily manufactured by injection molding or the like and can be manufactured at low cost.

Further, since the inner member is manufactured from a plate-shaped metal by press molding, the joint member is made of synthetic resin and can be formed in an arbitrary shape even when the shape of the inner member is limited. Therefore, it is possible to connect the inner member to the external device via the joint member.

The figure which shows the structure of the preferable embodiment of the torque limiter which concerns on this invention. An exploded perspective view of the torque limiter shown in FIG. The figure which shows the outer member of the torque limiter shown in FIG. 1 by itself. The figure which shows the inner member of the torque limiter shown in FIG. 1 by itself. The figure which shows the joint member of the torque limiter shown in FIG. 1 by itself. The figure which shows the other form of a joint member. The figure which shows the process of connecting a joint member shown in FIG. 5 to an inner member. The figure which shows the operation of the torque limiter shown in FIG.

Hereinafter, the torque limiter of the present invention will be described based on the drawings.

The torque limiter shown in FIG. 1 is a tubular outer member into which the inner member 2, the coil spring 4 mounted in contact with the outer peripheral surface of the inner member 2, and the inner member 2 mounted with the coil spring 4 are inserted. It has 6 and. For easy understanding, in the cross-sectional views of FIGS. 1 and 7, light ink is attached to the cross section of the inner member 2, and hatching is attached to the cross section of the outer member 6 and the joint member described later.

Explaining with reference to FIG. 3 together with FIGS. 1 and 2, the inner member 2 is made of metal and has a cylindrical shape as a whole. The inner member 2 includes a large diameter portion 8 located on one side in the axial direction and relatively short in the axial direction, a small diameter portion 10 located on the other side in the axial direction and relatively long in the axial direction, and a large diameter portion 8 and a small diameter portion 10. It is provided with a tapered portion 12 located in the middle of the above. An annular flange 16 is fixed to one end of the large diameter portion 8 in the axial direction via a trumpet-shaped portion 14 that extends outward in the axial direction toward the outside in the axial direction. That is, the inner member 2 of the present embodiment has a tubular shape whose diameter decreases from one end in the axial direction toward the other end. A pair of notches 18 having one end in the axial direction open are formed at one end in the axial direction of the inner member 2. Each of the pair of notches 18 is located opposite in the diametrical direction at the inner peripheral edge portion of the inner member 2, and at such a circumferential position, one side portion in the axial direction of the large diameter portion 8 and the entire trumpet-shaped portion 14 It is formed by removing the inner peripheral edge portion of the flange 16. Such an inner member 2 is manufactured by press molding from a plate-shaped metal in order to reduce the manufacturing cost.

As shown in FIGS. 1 and 2, the coil spring 4 is formed by winding a metal wire, and the inner diameter of the coil spring 4 in the natural state is smaller than the outer diameter of the small diameter portion 10 of the inner member 2, and the coil. The spring 4 is mounted in close contact with the outer peripheral surface of the small diameter portion 10 of the inner member 2. A hook portion 19 that stands up radially outward is formed at one end of the coil spring 4 in the axial direction.

Explaining with reference to FIG. 4 together with FIGS. 1 and 2, the outer member 6 is made of synthetic resin and has a cylindrical shape as a whole. Inside the outer member 6, one end in the axial direction has a large-diameter space portion 20 having substantially the same diameter as the outer diameter of the flange 16 of the inner member 2, and the other end in the axial direction has a small diameter portion of the inner member 2. A small-diameter space portion 22 having substantially the same diameter as the outer diameter of 10 is arranged on the inner peripheral surface at intervals in the circumferential direction between the large-diameter space portion 20 and the small-diameter space portion 22, which will be described later. An intermediate space portion 24 whose inner diameter changes in the axial direction due to the presence of a plurality of ridges is formed. On the inner peripheral surface of the outer member 6 forming the large-diameter space portion 20, a protrusion protruding inward in the radial direction, as understood by referring to the right view of FIG. 1 together with the cross-sectional view taken along the line AA of FIG. Three 26s are formed at equal intervals in the circumferential direction. A plurality of ridges 28 extending linearly in the axial direction are provided on the inner peripheral surface of the outer member 6 forming the intermediate space portion 24 at intervals in the circumferential direction. However, the ridge 28 is not provided at the angular position where the protrusion 26 is formed. This is due to molding reasons for forming the protrusions 26. The cross-sectional shape of the ridge 28 is a fan shape as a whole, and the inner diameter is larger in order from one end in the axial direction to the other end (that is, from right to left in the AA cross-sectional view of FIG. 4). A first portion 30 having the second largest diameter space portion 20, a second portion 32 having an inner diameter next to the first portion 30, and a third portion 34 having an inner diameter next to the second portion 32 are formed. The inner diameter of the third portion 34 is larger than that of the small diameter space portion 22. A locking groove 38 into which the hook portion 19 of the coil spring 4 is inserted is formed on the inner peripheral surface at the center of the region indicated by the number 36 on the outer peripheral surface of the outer member 6 by removing a part of the ridge 28. Will be done. Therefore, as shown in the cross-sectional view taken along the line AA, the ridge 28 remains at the other end of the locking groove 38 in the axial direction. On the outer peripheral surface of the outer member 6 in the predetermined region 36, a reinforcing ridge 40 having a substantially arcuate cross section formed by increasing the wall thickness outward in the radial direction is formed. The reinforcing ridge 40 extends linearly from one end in the axial direction toward the other end slightly beyond the locking groove 38 when viewed in the axial direction. The other side connecting portion 41 connected to the external device is fixed to the other end surface of the outer member 6 in the axial direction.

The inner member 2 to which the coil spring 4 is mounted is inserted into the outer member 6. Then, the small diameter portion 10 of the inner member 2 is supported by the small diameter space portion 22 of the outer member 6, and the large diameter portion 8 is supported by the inner peripheral surface of the outer member 6 in the third portion 34 of the intermediate space portion 24 of the outer member 6, respectively. The inner member 2 is thus relatively rotatably supported by the outer member 6 around a common central axis o. At this time, the hook portion 19 of the coil spring 4 is inserted into the locking groove 38 of the outer member 6, whereby the coil spring 4 is engaged with the outer member 6 so as not to rotate relative to each other. The portion of the coil spring 4 other than the hook portion 19 (that is, the portion around which the wire rod is wound) is the inner member 2 and the outer member 6 (more specifically, the ridge) in the third portion 34 of the intermediate space portion 24 of the outer member 6. It is located between 28).

The torque limiter configured in this way is the same as that of the conventional one, but in the torque limiter of the present invention, a joint member 42 made of synthetic resin is detachably connected to the inner member 2, and the inner member 2 is detachably connected. Is important to be connected to an external device via the joint member 42.

Explaining with reference to FIG. 5 together with FIGS. 1 and 2, the joint member 42 includes a connecting portion 44 connected to the inner member 2, a one-sided connecting portion 46 connected to an external device (not shown), and one side of the connecting portion 44. A circular partition plate 48 for partitioning the connection portion 46 is provided. The partition plate 48 is perpendicular to the axial direction, and the partition plate 48 is formed with a central hole 50 penetrating in the axial direction. The connecting portion 44 is provided on one side surface of the partition plate 48 in the axial direction, and has a cylindrical wall 52 that surrounds the central hole 50 and projects axially from the partition plate 48, and a partition plate along the outer peripheral surface of the cylindrical wall 52. It has a protrusion 54 that projects axially from 48 (see also the perspective view of the connecting portion). In the illustrated embodiment, a pair of protrusions 54 having a substantially rectangular cross section are fixed to the outer peripheral surface of the cylindrical wall 52 so as to face each other in the radial direction. A small positioning protrusion 56 that further protrudes in the axial direction is locally attached to the protruding end surface of the protrusion 54, more specifically, the outer end portion in the radial direction thereof. An annular flange 58 is also fixed to the outer peripheral edge of the partition plate 48. The flange 58 is provided coaxially with the common central axis, and extends outward in the radial direction beyond the outer peripheral edge of the partition plate 48. The annular flange 58 surrounds the base end of the cylindrical wall 52 and the protrusion 54. The one-sided connecting portion 46 is provided on one side surface of the partition plate 48 in the axial direction. In the illustrated embodiment, the one-sided connecting portion 46 is composed of two arcuate pieces 60 projecting axially along the outer circumference of the central hole 50, and the two arcuate pieces 60 face each other in the radial direction at intervals. It is provided. A connection receiving portion of an external device (not shown) is connected to the two arcuate pieces 60, which are the one-sided connecting portions 46. Since the one-sided connection portion 46 needs to have a shape corresponding to the connection receiving portion of the external device to which it is connected, for example, instead of forming the one-side connection portion 46 with two arc-shaped pieces 60, for example. , A cylindrical portion having a D hole formed in the center as shown by No. 60a in FIG. 6A (a joint member having this is shown by 42a), or shown by No. 60b in FIG. 6B. Such a D-shaped protrusion (a joint member equipped with this is shown by 42b), or a cylindrical portion having a key groove as shown by number 60c in FIG. 6 (c) (a joint provided with this). The member may be indicated by 42c). Such a joint member 42 is formed by compression molding an appropriate synthetic resin material.

The above-mentioned joint member 42 is connected to the inner member 2 inside the outer member 6. The process of connecting the joint member 42 to the inner member 2 will be described with reference to FIG. 7. First, as shown in FIG. 7A, the joint member 42 is arranged so that the connecting portion 44 faces the one end portion in the axial direction of the inner member 2 (that is, the end portion on which the flange 16 is formed). .. Next, the joint member 42 is brought close to one end in the axial direction of the inner member 2, and the positioning small protrusion 56 of the connecting portion 44 is inserted into the notch 18 as shown in FIG. 7 (b). At this time, the flange 58 of the joint member 42 comes into contact with the outer surface of the protrusion 26 formed on the inner peripheral surface of the outer member 6. After that, as shown in FIG. 7C, when the joint member 42 is forced to the left in the same figure, the flange 58 elastically overcomes the protrusion 26, and the entire protrusion 54 is inserted into the notch 18. The cylindrical wall 52 is also inserted inside the large diameter portion 8 of the inner member 2 (see also the cross-sectional view taken along the line AA of FIG. 1), thus connecting the joint member 42 to the inner member 2. In the present embodiment, as described above, the protrusion 54 and the notch 18 are ensured by inserting the positioning small protrusion 56 into the notch 18 prior to inserting the protrusion 54 into the notch 18. The joint member 42 can be easily connected to the inner member 2. Further, by inserting the cylindrical wall 52 of the joint member 42 into the inside of the large diameter portion 8 of the inner member 2, the cylindrical wall 52 fits on the common central axis o with the large diameter portion 8 of the inner member 2. .. In other words, the inner member 2 and the outer member 6 are fitted by a fitting means having a circular cross section that fits each other on a common central axis o. As a result, the joint member 42 is stably connected to the inner member 2 without rattling. Then, when the flange 58 elastically overcomes the protrusion 26, the flange 58 is formed between the protrusion 26 and the ridge 28 (that is, two axially spaced ends on the inner peripheral surface of the outer member 6). It is sandwiched (by the protrusions) and holds the axial position of the joint member 42 with respect to the outer member 6. As a result, the joint member 42 is prevented from unexpectedly falling off from the inner member 2 and the outer member 6.

The operation of the torque limiter according to the present invention combined in this way will be described with reference to FIG. When a rotational torque (torque in a direction that relaxes the tightening force of the coil spring 4) around the central axis o that relatively rotates the inner member 2 and the outer member 6 is applied, the rotational torque is larger than a predetermined value. In this case, the outer member 6 and the inner member 2 rotate relative to each other by overcoming the frictional force between the inner member 2 and the outer member 6 (FIG. 8A). In the illustrated embodiment, only one hook portion 19 is formed on the coil spring 4, and the inner member 2 is viewed from the right side of the AA cross-sectional view of FIG. 8 with respect to the outer member 6 ( (The same applies to the BB sectional view) It rotates only in the counterclockwise direction. From this, the direction in which the tightening force of the coil spring 4 is relaxed means the counterclockwise direction when viewed from the right side of the AA cross-sectional view of FIG. 8 (the same applies to the BB cross-sectional view). .. On the other hand, if the rotational torque for relatively rotating the inner member 2 and the outer member 6 is equal to or less than a predetermined value, the outer member 6 and the inner member 2 are caused by the frictional force between the inner member 2 and the coil spring 4. The outer member 6 does not rotate relatively, and the outer member 6 rotates in the above direction integrally with the coil spring 4 and the inner member 2 (FIG. 8 (b)).

The joint member 42 is appropriately replaced according to the shape of the connection receiving portion of the external device to which the inner member 2 is connected. In the illustrated embodiment, when the joint member 42 and the outer member 6 are combined, the flange 58 of the joint member 42 has two protrusions (that is, protrusions) formed on the inner peripheral surface of the outer member 6. Since it is sandwiched in the axial direction by 26 and the ridge 28) and the axial position of the joint member 42 with respect to the outer member 6 is held, when the joint member 42 is replaced, the flange 58 is twisted or the like. Try to get over the protrusion 26 again. At this time, since the joint member 42 is made of synthetic resin, it can be elastically deformed, and therefore the joint member 42 can be relatively easily removed from the outer member 6.

In the torque limiter of the present invention, a joint member made of synthetic resin is detachably connected to the inner member, and the inner member is connected to an external device via the joint member. Therefore, if a plurality of joint members are prepared in advance according to the external device to be connected, the main configuration of the torque limiter can be maintained and only the joint member can be replaced with an appropriate one to connect to each external device. This makes it possible to reduce the manufacturing cost and facilitate the management and storage of the torque limiter as a product. In particular, since the joint member of the present invention is made of synthetic resin, it can be easily manufactured by injection molding or the like and can be manufactured at low cost. Further, since the inner member is manufactured from a plate-shaped metal by press molding, the joint member is made of synthetic resin and can be formed in an arbitrary shape even when the shape of the inner member is limited. Therefore, it is possible to connect the inner member to the external device via the joint member.

Although the torque limiter of the present invention has been described in detail with reference to the attached drawings, the present invention is not limited to the above-described embodiment, and various modifications can be considered. For example, in the illustrated embodiment, the coil spring is formed with only one hook portion, and the rotation direction of the inner member with respect to the outer member is limited to one direction. Two hooks are provided, and when the inner member rotates with respect to the outer member, a locking groove is formed so that one of the two coil springs is pushed in the direction of loosening the coil spring. It is also possible to allow the inner member to rotate in both directions with respect to the member (see JP-A-10-78044 previously filed by the applicant of the present application). Further, in the illustrated embodiment, the inner member and the joint member are connected by a notch and a protrusion, but the inner member and the joint member need only be engaged in at least the circumferential direction, and the inner member It is clear that the two can be combined in different forms depending on the shape.

2: Inner member 4: Coil spring 6: Outer member 18: Notch 41: Other side connection part 42: Joint member 44: Connection part 46: One side connection part 54: Protrusion 56: Positioning small protrusion

Claims

A metal inner member, a coil spring mounted in contact with the outer peripheral surface of the inner member and formed by winding a wire rod, and a tubular outer side into which the inner member mounted with the coil spring is inserted. Equipped with members
The inner member and the outer member have a common central axis, and the coil spring is engaged with the outer member so as not to rotate relative to each other.
When a rotational torque around the central axis that relatively rotates the inner member and the outer member is applied, when the rotational torque is larger than a predetermined value, between the inner member and the outer member. In a torque limiter in which the outer member and the inner member rotate relative to each other by overcoming the frictional force.
A torque limiter characterized in that a joint member made of synthetic resin is detachably connected to the inner member, and the inner member is connected to an external device via the joint member.
The torque limiter according to claim 1, wherein the inner member and the joint member are connected by a notch having an open axial end and a protrusion protruding in the axial direction.
A positioning small protrusion that further protrudes in the axial direction is locally attached to the protruding end surface of the protrusion, and the positioning small protrusion is cut in advance of inserting the protrusion into the notch. The torque limiter according to claim 2, which is inserted into the notch.
The joint member is provided with an annular flange coaxially with the common central axis, and protrusions protruding inward in the radial direction are axially spaced on the inner peripheral surface of the outer member. Two are formed
The torque limiter according to any one of claims 1 to 3, wherein when the joint member and the outer member are combined, the flange is sandwiched by the two protrusions.
The torque limiter according to any one of claims 1 to 4, wherein the inner member and the outer member are provided with fitting means having a circular cross section for mating with each other on the common central axis.
The torque limiter according to any one of claims 1 to 5, wherein the inner member has a tubular shape whose diameter decreases from one end in the axial direction toward the other end.
The torque limiter according to any one of claims 1 to 6, wherein the inner member is manufactured from a plate-shaped metal by press molding.