JPH11124219A - Positioning tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide both a function as a roller and a positioning function and to facilitate fastening against a rotary shaft by the small number of parts. SOLUTION: A positioning tool 1 comprises a body 4 and a roller part 2 and a whole is integrally formed of a synthetic resin material. In the body part 4, a pair of slits 7 and 8 are formed in a spot positioned facing each other with the axis L of a rotary shaft 3 nipped therebetween. The body 4 is divided into two arcuate parts 9 and 10 formed in a semicircular shape by the two silts 7 and 8. Screw mounting parts 11 and 12 are arranged on two side parts of each of the slits 7 and 8 of the body part 4. By fastening the screw member 16 by the mounting parts 11 and 12, the body part 4 is elastically deformed and fastened against the rotary shaft 3. The outer peripheral surface 15 of the roller part 2 forms a smooth surface paralleling the axis L in any spot.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positioning tool used for accurately mounting components such as gears, sprockets and bearings in the axial direction, and more particularly to a positioning tool having a function as a roller. It is.

[0002]

2. Description of the Related Art Conventionally, for example, a large number of rollers are arranged,
There is known a mechanism in which conveyed objects, such as paper, placed thereon are sequentially sent out by rotation of the rollers. In this mechanism, each roller is attached to a predetermined position of the rotating shaft so as to be integrally rotatable. At this time, a general roller is provided with a shaft insertion hole for fitting the roller to a rotating shaft, but is not provided with a mechanism for positioning in the axial direction.

[0003] Therefore, a technique has been widely adopted in which two dedicated positioning tools are fastened to the rotating shaft, and the roller is sandwiched between the two positioning tools. As shown in FIG. 4, the positioning tool includes a C-shaped main body 36 into which a slit 35 is inserted and made elastically deformable, and a screw member 37 connecting both ends of the main body 36. is there. In this type, both ends of the main body 36 are elastically deformed by tightening the screw member 37 and fastened to the rotating shaft 33. In addition, the positioning tool includes a pair of arc members having a semicircular shape and fitted to the rotating shaft, and a pair of screw members connecting end portions of the arc members (shown in the drawing). Abbreviation). Also in this type, similar to the positioning tool described above,
Both arc members are elastically deformed by tightening the screw members and fastened to the rotating shaft.

[0004]

However, in any of the prior arts described above, two positioning tools must be prepared in addition to the rollers 34. In addition, the two positioning tools must be fitted to the rotating shaft 33 and the screw member 37 must be tightened, which causes a problem that the mounting operation is troublesome.

It is noted that the positioning tool has a substantially annular shape and may be used as a roller as it is. However, there are places on the outer peripheral surface 38 of the positioning tool that are not smooth. This portion includes a concave portion 39 for accommodating the head 37a of the screw member 37, a slit 35, and the like. Then, there is a possibility that the conveyed object such as paper may be damaged due to these portions. Therefore, depending on the type of the transferred object, the positioning tool may not be used as a roller as it is.

Accordingly, an object of the present invention is to provide a positioning tool which has both a function as a roller and a positioning function, and can be easily mounted on a rotating shaft with a small number of components.

[0007]

According to a first aspect of the present invention, at least one slit for communicating an outer surface of the main body with a shaft insertion hole with the shaft insertion hole is formed in a main body having the shaft insertion hole. In a positioning tool provided with screw mounting portions on both sides of a slit in the main body portion, the main body portion is elastically deformed by tightening a screw member at the screw mounting portion and fastened to a rotating shaft. In addition, a roller portion having a smooth outer peripheral surface is integrally formed.

[0008] Here, the "screw mounting portion" is a portion to which a screw member is attached. The “screw member” is a member in which a protrusion (thread) having a uniform cross section is formed in a coil shape on the surface of a cylinder or a cone, and includes a bolt, a small screw, a combination of a bolt and a nut, and the like. . The screw mounting part is
In addition to a through hole with both ends opened, it has a hole with only one end opened. Further, on the inner peripheral surface of these through holes and holes, female threads are formed as necessary in consideration of the type of screw member and the like. For example, when a combination of a bolt and a nut is used, an internal thread is unnecessary, but when a nut is not used, an internal thread is required. Also,
"Smooth" refers to a state in which the cross-sectional shape of the outer peripheral portion of the roller portion is uniform. This includes the state where such grooves and ridges are formed.

According to the first aspect of the invention, when the positioning tool is mounted on the rotary shaft, the main body and the roller are fitted to the ends of the rotary shaft in the shaft insertion holes. At this time, the screw member is removed or loosened from the screw mounting portion. Then, the main body and the roller are moved to a predetermined position on the rotating shaft. At this time, since the roller portion is formed integrally with the main body portion, both move integrally. When the main body and the roller reach a predetermined position, the movement is stopped, and the screw member is tightened at the screw mounting portion. Then, the main body is elastically deformed so as to reduce the width of the slit, and the main body is fastened so as to be relatively immovable in both the rotating direction and the axial direction of the rotating shaft. The roller unit is not directly fastened to the rotating shaft, but is indirectly fastened to the rotating shaft via the main body.
In other words, the main body is fastened to the rotating shaft, thereby exerting a function of positioning the roller in the axial direction.

The positioning tool fastened to the rotating shaft rotates integrally with the rotating shaft. When a conveyed object such as paper is conveyed by a roller, a smooth outer peripheral surface of the roller contacts the conveyed object.

The positioning tool has a function of positioning a component mounted on the rotating shaft in the axial direction. That is, the positioning tool mounted on the rotating shaft restricts the axial movement of the component by contact with the component.

According to a second aspect of the present invention, in addition to the configuration of the first aspect, the main body and the roller are formed of a polymer material or a non-ferrous metal material. Here, the polymer material includes a synthetic resin material and rubber.

According to the second aspect, a general polymer material or a non-ferrous metal material has a characteristic that its specific gravity is smaller than that of a metal material such as iron or stainless steel. Therefore,
When the main body and the roller are formed of a polymer material or a non-ferrous metal material, the weight is reduced as compared with the case where the main body and the roller are formed of a metal material such as iron. Accordingly, the rotational moment during rotation of the positioning tool is reduced, which is advantageous when the positioning tool is rotated at a high speed. Further, a general polymer material or a non-ferrous metal material has a feature of being excellent in rust prevention unlike metal materials such as iron. Therefore,
No rust is generated on the surface of the positioning tool including the roller, regardless of the use environment. When a conveyed object such as paper is conveyed by the roller unit, the outer peripheral surface of the clean roller unit always comes into contact with the conveyed object.

According to a third aspect of the present invention, in addition to the configuration of the first or second aspect, the slit is formed at a position facing each other across the axis of the rotation shaft, and A portion is provided for each slit.

According to the third aspect of the invention, when the screw member is tightened for each screw mounting portion when the positioning tool is mounted on the rotating shaft, the two opposing portions of the main body with the axis interposed therebetween are elastic. It is deformed and fastened to the rotating shaft.

Here, the distance in the axial direction from the roller portion to a portion (screw member) related to fastening in the main body portion is defined as an offset amount. Within a predetermined range, the fastening force tends to increase as the offset amount increases. On the other hand, in the third invention in which two sets of slits and screw mounting portions are provided, the fastening force is sufficiently large. Therefore, under the condition that the same fastening force is obtained as in the case where one set of the slit and the screw mounting portion is provided, the offset amount is small. That is, the body is fastened to the rotating shaft at a location closer to the roller.

In manufacturing the positioning tool, the workpiece may be cut by a milling machine (milling) in order to form a slit. Here, the "workpiece" is an unprocessed material or a part in an intermediate stage before becoming a final product. In processing, the workpiece and the cutter are relatively moved so that the milling cutter of the milling machine passes through the axis. Then, a pair of slits are formed at a time at locations facing each other across the axis in the main body.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS.

As shown in FIG. 1, a positioning tool 1 includes a roller portion 2 having a shaft insertion hole (not shown) at a center portion, and a roller portion 2 fitted on a rotating shaft 3 in the shaft insertion hole.
And a main body 4 that locks the rotation shaft 3 so that it cannot rotate relative to the rotation shaft 3 and cannot move in the axial direction.
The roller section 2 and the main body section 4 are formed by cutting a bar made of a synthetic resin material. In this embodiment, a polyacetal resin, which is a kind of engineering plastic, is used as a synthetic resin material. The resin is a thermoplastic resin obtained by the polymerization of formaldehyde, which is lighter than metal,
Excellent in toughness, wear resistance, molding accuracy, etc. Further, the polyacetal resin has a feature that it does not rust like the other synthetic resins.

As shown in FIG. 2, the main body 4 has a shaft insertion hole 5 at the center thereof, and has a substantially annular shape as a whole. A pair of slits 7 and 8 for communicating the outer peripheral surface 6 and the shaft insertion hole 5 are formed in the main body 4 by cutting using a milling machine (milling). In the present embodiment, these slits 7 and 8 are formed on a predetermined plane P passing through the axis L of the rotating shaft 3 at locations facing each other across the axis L (left and right in FIG. 2). That is, the workpiece and the cutter are relatively moved so that the milling cutter of the milling machine passes through the plane P, and two slits 7 and 8 are formed. Due to the presence of these slits 7 and 8, the main body 4 is divided into two semicircular arcs 9 and 10. However, each of the arc portions 9 and 10 is connected to the roller portion 2 at a root portion thereof.

Screw mounting portions 11 and 12 are provided on both sides of each of the slits 7 and 8 in the main body portion 4. Each of the screw mounting portions 11 and 12 includes a concave portion 13 provided at an end of the arc portion 9 and a hole 14 extending in a direction orthogonal to the slits 7 and 8 and connected to the concave portion 13. Hole 14 on the side of the arc 10
Is a so-called screw hole having an internal thread on the inner periphery.

As shown in FIG. 3, the roller 2 is
The main body 4 is formed integrally with one side (the right side in the figure) of the main body 4. The outer peripheral surface 15 of the roller portion 2 is formed as a smooth surface. More specifically, the outer peripheral surface 15
Are parallel to the axis L at any point. A part of the outer peripheral surface 6 of the main body 4 is missing due to the slits 7, 8 and the concave portion 13, and a step is generated in the main body 4, whereas the outer peripheral surface 15 of the roller 2 is missing part. And there is no step as described above.

Although the positioning tool 1 is constructed as described above, the positioning tool 1 is attached to the rotating shaft 3 by two steps.
This is performed as follows using the book screw member 16. Here, a hexagon socket head bolt is used as the screw member 16, but the present invention is not limited to this. First, the main body portion 4 and the roller portion 2 are fitted to the end of the rotating shaft 3 in the shaft insertion hole 5. At this time, the screw member 16 is removed or loosened from the screw mounting portions 11 and 12. Then, a force in the axial direction is applied to at least one of the main body 4 and the roller 2. Then, the portion where the force is applied (for example, the main body 4)
Not only the part that is not directly added (roller part 2)
Are also moved in the axial direction.

When the main body portion 4 and the roller portion 2 reach the predetermined positions, the application of the axial force is stopped, and the screw members 16 are tightened at both the screw mounting portions 11 and 12, respectively. Then, a tensile force (tightening force) is generated in each screw member 16, and the main body 4 is elastically deformed so that the widths of the slits 7, 8 are reduced with the roots of the arcs 9, 10 as a base point. Due to this elastic deformation, the main body 4 is fastened so as to be relatively immovable in both the rotating direction and the axial direction of the rotating shaft 3. In particular, in the present embodiment, two sets of the slits 7 and 8 and the screw mounting portions 11 and 12 are provided, so that the fastening force increases as compared with the case where one set is provided, and the main body 4 is rotated with a large force. Fixed to 3. Further, since the two sets of slits 7 and 8 and the screw mounting portions 11 and 12 are located opposite to each other with the axis L interposed therebetween, the tensile force due to the tightening of the screw member 16 is locally biased with respect to the main body 4. Never join. It is also advantageous from the viewpoint of balance of weight and the like. The roller portion 2 is not directly fastened to the rotating shaft 3 unlike the main body portion 4 due to its structure. However, the roller 2 is indirectly fastened to the rotating shaft 3 via the main body 4. In other words, the main body 4 exerts a function of positioning the roller 2 in the axial direction by being fastened to the rotating shaft 3.

As shown in FIG. 3, an axial distance from an arbitrary position (for example, the front surface) of the roller portion 2 to a portion (the screw member 16) related to the fastening in the main body portion 4 is represented by an offset amount OS. And Generally, in a predetermined range, the fastening force tends to increase as the offset amount OS increases. On the other hand, in this embodiment, the fastening force is increased by providing two sets of the slits 7 and 8 and the screw mounting portions 11 and 12 as described above. Therefore, under the condition that the same fastening force is obtained as when one set of the slit and the screw mounting portion is provided, the offset amount O
S is small. That is, the body 4 is fastened to the rotating shaft 3 at a position closer to the roller 2. As a result, the thickness t of the main body 4 can be reduced, and the positioning tool 1 can be made compact. This is particularly effective when the mounting space of the positioning tool 1 is limited.

Since the roller portion 2 is attached to the rotating shaft 3 as described above, unlike the prior art, there is no need to prepare another part for positioning the roller portion 2. The work of fastening another part on the rotating shaft 3 is not required, and the attachment to the rotating shaft 3 is made easier. That is, in the prior art, since the roller 34 itself has no positioning function, the roller 34
Separately, two positioning tools are attached to regulate the movement of the roller 34 in the axial direction. On the other hand, in the present embodiment, the roller unit 2 corresponding to the conventional roller 34 and the main body unit 4 corresponding to the conventional positioning tool are already integrated at the product stage. For this reason, the connection between the main body 4 and the roller 2 is not required at the time of attachment to the rotating shaft 3. Further, if the main body 4 is fixed, the movement of the roller 2, particularly the movement in the axial direction, is restricted by the main body 4. Therefore,
The roller unit 2 can be connected to the rotating shaft 3 without increasing the number of parts.
Can be easily fastened.

When the rotating shaft 3 rotates, the positioning tool 1 rotates integrally with the rotating shaft 3. This positioning tool 1
In FIG. 2, as shown in FIG.
An object 17 such as paper comes into contact with 5. This transferred object 17
Are sequentially sent by the rotation of the roller unit 2. Here, the roller section 2 is different from the main body section 4 in that a slit 7
8. There is no step due to the recess 13 or the like, and the outer peripheral surface 15 is a smooth surface. For this reason, there is no possibility of inadvertently damaging the transferred object 17 during the transfer by the roller unit 2.

The specific gravity of the polyacetal resin, which is the material of the main body portion 4 and the roller portion 2, is smaller than that of metal materials such as iron and stainless steel. For this reason, the body 4 and the roller 2 are lighter than those made of the metal material. Accordingly, the rotational moment of the positioning tool 1 during rotation is reduced, which is advantageous when the positioning tool 1 is rotated at a high speed. The positioning tool 1 made of a synthetic resin is suitable for a case where the article 17 is conveyed quickly.

Further, a general synthetic resin material containing a polyacetal resin is characterized by having excellent rust prevention.
Therefore, the roller unit 2 can be used in any usage environment.
No rust is generated on the surface of the positioning tool 1 including.
The clean outer peripheral surface 15 without rust always comes into contact with the transferred object 17. As a result, unlike the case where the positioning tool is manufactured using a metal material such as iron, the transferred object 17 can be prevented from being stained by rust.

As described above, the slits 7 and 8 are formed by cutting using a milling cutter. If the number of the slits is one, it is difficult to make the outer peripheral surface of the main body 4 and the shaft insertion hole 5 communicate with each other neatly without cutting extra portions of the main body 4 other than the slits. is there. This is because the milling cutter has a disk shape, and the degree of cutting differs depending on the position of the main body 4. More specifically, even if the cutter does not cut a portion other than the portion where the slit is to be formed, it may not be able to cut completely and cannot form a complete slit even if it enters deep inside the main body 4. In this case, further processing is required. On the other hand, in the present embodiment, the number of the slits is two, and they are located at positions facing each other across the axis L, that is, on the plane P including the axis L.
For this reason, when the workpiece and the cutter are relatively moved so that the milling cutter passes through the plane P, a pair of slits 7 and 8 are formed at once in the main body 4 at locations facing each other across the axis L. You. As described above, the two slits 7 and 8 having a desired shape can be reliably formed without excessive cutting in a very simple and small number of steps (man-hours) of relatively moving the workpiece and the milling cutter in one direction. And cost reduction can be achieved.

The present invention can be embodied in another embodiment described below.

(1) As the synthetic resin material, a material other than the above-mentioned polyacetal resin, for example, a polyamide resin,
A polycarbonate resin, a modified polyphenylene ether resin, a polybutylene terephthalate resin, or the like may be used. Further, instead of the synthetic resin material, various rubbers (including synthetic rubber such as urethane rubber and natural rubber) may be used, or iron,
A metal material such as stainless steel, aluminum, or brass may be used. In addition, the high-speed rotation of the positioning tool 1 and the transfer object 1
From the viewpoint of preventing rust from adhering to 7, it is desirable to use a material that is light and hard to rust, such as a synthetic resin material, rubber, or a non-ferrous metal material.

(2) Although the positioning tool 1 having the two slits 7 and 8 has been described in the above embodiment, the number of the slits may be changed to one or three or more.
When there is one slit, the root portion of the main body 4 (the main body 4
A groove orthogonal to the axis L may be formed in a part of the boundary between the roller portion 2 and the roller portion 2). In this formation, the groove passes through the base of the slit. This way,
The elastic deformation of the screw mounting portion 12 when the screw member 16 is tightened becomes easy.

(3) When manufacturing the positioning tool 1, a method other than cutting may be employed. Examples of this method include a resin molding method in which a molten resin is injected into a mold and cooled and solidified, and a casting method in which a molten metal is poured into a mold and cooled and solidified.

(4) The roller portion 2 does not necessarily have to have a larger diameter than the main body portion 4 and may have the same diameter as the main body portion 4 or may have a smaller diameter than the main body portion 4.

(5) The positioning device according to the present invention comprises a roller 2
The present invention is not limited to the case of transporting paper and the like, and may be used for positioning of components such as gears, sprockets and bearings mounted on the rotating shaft 3 in the same manner as a conventional positioning tool. In this case, the axial movement of the component can be restricted by the side surface of the roller portion 2 or the side surface of the main body portion 4.

(6) When the positioning tool is formed of a metal material which may generate rust, it is desirable to apply a surface treatment such as plating to the positioning tool.

(7) The outer shape of the main body 4 may be changed to a shape other than a circle, for example, a polygon, an ellipse, or the like.

(8) In FIG. 2, when a combination of a bolt and a nut is used as the screw member 16, a concave portion similar to the concave portion 13 of the circular arc portion 9 is provided at both ends of the circular arc portion 10 and a hole is formed. The female screw in 14 is omitted. Then, it is desirable that the head of the bolt is disposed in the concave portion 13 on the arc portion 9 side and the nut is disposed in the concave portion on the arc portion 10 side.

[0040]

As described above, according to the first aspect, a positioning tool having both a function as a roller and a positioning function can be provided. Since the roller portion is integrated with the main body portion, it is only necessary to fasten the main body portion to the rotary shaft when mounting the roller portion on the rotary shaft. Separate parts for positioning the roller are not required,
The number of parts can be reduced. Accordingly, the work of fastening the separate parts becomes unnecessary, and the attachment to the rotating shaft is facilitated accordingly.

According to the second aspect, in addition to the effects of the first aspect, the positioning tool can be rotated at a high speed. Further, when the transported object is transported by using the positioning tool as a roller, it is possible to prevent rust from attaching to the transported object.

According to the third aspect, in addition to the effects of the first or second aspect, the fastening force is increased as compared with the case where one set of the slit and the screw mounting portion is provided, and the main body is attached to the rotating shaft. On the other hand, it can be firmly fastened in a state where the weight and the like are balanced. Further, the body can be made thinner by reducing the offset amount. Furthermore, when the slit is formed by cutting, the processing can be performed in a simple and small number of steps, and the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view of a positioning tool according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a side view of the positioning tool.

FIG. 4 is a perspective view showing a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Positioning tool 2 Roller part 3 Rotating shaft 4 Main body part 5 Shaft insertion hole 6,15 Outer peripheral surface 7,8 Slit 11,12 Screw mounting part 16 Screw member L Axis

Claims (3)

[Claims] 1. A main body having a shaft insertion hole, at least one slit for communicating an outer surface of the main body with the shaft insertion hole is formed, and a screw mounting portion is provided on both sides of the slit in the main body. In a positioning tool configured to elastically deform a main body by tightening a screw member at a mounting portion and to fasten the main body to a rotating shaft, a roller having a smooth outer peripheral surface is integrally formed on one side of the main body. Characteristic positioning tool. 2. The positioning tool according to claim 1, wherein the main body and the roller are formed of a polymer material or a non-ferrous metal material. 3. The slit according to claim 1, wherein the slits are formed at locations facing each other with the axis of the rotation shaft interposed therebetween, and the screw mounting portion is provided for each of the slits. Positioning tool.