JPH08312758A - Pulley assembly - Google Patents

Abstract

PURPOSE: To reduce the cost factor of a mold, to facilitate handling, and to maintain precision by a method wherein a protrusion and recessed part are symmetrically arranged in such a manner to be positioned facing each other for intercoupling and through fitting-in of the protrusion and the recessed part of a division member, to form a pulley with both side ribs. CONSTITUTION: A cylinder part 2 axially stretched from the flange part 3 of a division member 1 has an inner peripheral surface by which a space is formed and ribs 5 serving as a cylinder part holding means are formed in four spots. Protrusion 5-1 and a recessed part 5-2 are alternately formed in the tips of the four ribs 5. The protrusion 5-1 and the recessed part 5-2 are sized to be engaged with each other and positioned facing each other for fitting-in to form a pulley assembly. Since integral holding is effected as the pulley assembly, a shaft member is inserted through in two holes 4 for a shaft which have the same size as each other and are positioned facing each other for interconnection. Since constitution is effected through combination of the same shapes, the cost factor of a mold is reduced and since fitting-in means are axially symmetrically constituted, a pulley assembly handling of which is easy to make and which is advantageous to precise maintenance is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a pulley assembly with a collar.

[0002]

2. Description of the Related Art FIG. 7 is a side view of a conventional pulley having two flanges on both sides. The pulley has flanges 3 on both end faces of a cylindrical portion 2 and a shaft is fitted to the center of the cylindrical portion 2. A shaft hole 4 is provided. Since the pulley shown in FIG. 7 has the flanges 3 on both sides of the cylindrical portion 2, for example, in order to form it by resin molding, a molding die is used to form the outer peripheral surface as shown in the explanatory view shown in FIG. Various ideas have been made, such as molding in four directions or molding in two in the axial direction.

In the molding means with a mold divided in the circumferential direction, the mold is divided and the molding operation direction is different, and the mold or equipment is divided into two parts in the axial direction for forming the central shaft hole. In addition to being disadvantageous in terms of cost, there was a further cost-increasing factor, such as the fact that so-called parting line burrs remained on the outer peripheral surface of the cylindrical portion and it was unavoidable to remove it.

Further, in the axially divided structure, as shown in FIGS. 9 and 10, a structure in which fitting means asymmetrical with respect to the central axis of the turning motion is used for coupling is adopted. As shown in the figure, a shaft hole 4 is provided at the center of the cylindrical portion 2 provided with one flange 3,
Provided on the end surface of the cylindrical portion 2 where the collar 3 is not provided, is a convex portion obtained by cutting a part of the cylinder along the plane 9 and a flange 3'that fits into the convex portion is fitted and a pulley having both collars is provided. Is forming. That is, since it is difficult to ensure the accuracy of the shaft hole in the divided members, the connecting and fixing means other than the shaft fitting portion is formed so as not to divide the shaft hole.

[0005]

However, the conventional structure as described above has problems such as the cost of the mold and the accuracy of the asymmetric coupling fitting means.

[0006]

In the pulley assembly according to the present invention, each of the split members has a collar portion, a cylindrical portion axially extending from one surface of the collar portion, and ribs on the inner peripheral surface of the cylindrical portion. And a coupling protrusion or a recess integrally formed at the tip of the rib, and the same shape members are coupled to face each other, and the protrusion or the recess of the split member is fitted to form a pulley with two-sided collars. Each of the divided members is provided with a collar portion and a cylindrical portion axially extending from one surface of the collar portion and ribs on the inner peripheral surface of the cylindrical portion, and the other is formed with the collar portion and one surface of the collar portion. And a parallel protrusion that faces the rib of the one of the split members and sandwiches the rib, and the protrusion and the rib are fitted together to form a pulley with ribs on both sides. Or one of the divided members includes a cylindrical portion and a circle A rib on the inner peripheral surface of the section and a coupling projection or recess that is integral with the tip of the rib are provided, and the other split member has a cylindrical portion different from the one split member and the projection or recess of the one split member. Is provided, and the pulley assembly is constructed by fitting the both.

[0007]

[Operation] In the above-mentioned configuration, cost factors such as molds can be reduced by combining the same shapes, and the fitting means is configured to be axially symmetric, so that the handling accuracy can be maintained easily. An advantageous and excellent pulley assembly can be obtained.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows one embodiment 1 of a dividing member according to the present invention, in which a cylindrical portion 2 axially extending from a flange portion 3 has a space at its inner peripheral surface to form a cylindrical portion holding means at four positions. The rib 5 is formed on the. FIG. 2 is a cross-sectional view of the pulley assembly shown in FIG. 1 in which the two split members 1 shown in FIG. 1 are fitted to face each other. As shown in FIG. The protrusion 5-1 and the recess 5-2 are formed. The protrusion 5
-1 and the recessed portion 5-2 have fitting dimensions with each other, and are fitted to face each other as shown in FIG. 2 to form a pulley assembly.
In order to integrally hold the pulley assembly, the shaft members are inserted into both shaft holes 4 facing each other and having the same size and connected to each other.

3 and 4 are front views of another example according to the present invention, in which one of the split members shown in FIG. 3 has ribs 5 formed on the inner peripheral surface of the cylindrical portion 2. The other split member shown in FIG. 4 does not include the rib 5 and is provided with a plurality of pairs of projections 7 extending in parallel to the axial direction from the end surface on which the collar portion 3 is formed. The parallel protrusions 7 are the ribs 5 of the one split member.
The two ribs 5 are provided so as to be symmetrical with respect to each other and are fitted to each other so as to sandwich the respective ribs 5 therebetween.

In this example, the two divided members are not the same type member, but the fitting connection portion is formed in axial symmetry, and the shaft hole 4 is axially opposed to each other in the same manner as in the first example. They are connected to each other, and the coaxiality is maintained by fitting the spigot portion 6.

5 and 6 are sectional views showing a fitted state of still another example according to the present invention. In FIG. 5, one division member 10 has a collar portion 3 and a cylindrical portion 2 and the other division member. Reference numeral 11 is an example constituted only by the flange portion 3, and FIG. 6 is an example of a stepped pulley by connecting another member having cylindrical portions having different dimensions. Figure 5
In the example, one of the split members 10 includes a collar portion 3, a cylindrical portion 2, a rib 5 on an inner diameter portion of the cylindrical portion 2, and a spigot portion 6 on one end of the cylindrical portion 2.
And the other split member 11 includes a collar portion 3 and a spigot portion 6.
And a protrusion 7 for sandwiching the rib 5 is provided on the end face of the spigot portion.

The example of FIG. 6 is an example of a step pulley in which members having different outer diameters of the cylindrical parts of the one divided member 12 and the other divided member 13 are connected. One of the dividing members 12 is provided with a collar portion 3, a cylindrical portion 2, a rib 5 on the inner diameter portion of the cylindrical portion 2, a convex portion 5-1 and a concave portion 5-2 at the tip of the rib 5, and the other dividing member 1
3 is provided with a collar portion having the same outer diameter as the collar portion 3 of the one division member 12, a cylindrical portion 2 ′ having an outer diameter different from the cylindrical portion 2 of the one division member 12, and a collar portion 3 ′. Convex portion 5-1 provided at the tip of the rib 5 on the end surface of the collar portion having the same outer diameter as the portion 3.
And the concave portion 5-2 are provided, and the convex portion 5-1 and the concave portion 5-2 of both are provided.
Are fitted and the split members 12 and 13 are joined to form a stepped pulley. In both cases, the fitting structure of the divided members is based on the projection and the recess formed at the tip of the rib. Of course, the fitting means may be the rib shown in FIGS. 3 and 4 and the parallel projection that sandwiches the rib. The shaft hole 4 is axially opposed and connected.

The timing belt is meshed with the outer diameter portion of the cylindrical portion 2, 2'of the pulley of the embodiment of the present invention described and shown in FIGS. 1, 2, 3, 4, 5 and 6. It is also possible to provide teeth to be used.

[0014]

Since the pulley assembly according to the present invention is constructed as described above, it is possible to reduce the cost factors such as molds by the combination of the same shapes and the fitting means is axially symmetrical. By doing so, it is possible to obtain an excellent pulley assembly which is easy to handle and advantageous in maintaining accuracy.

[Brief description of drawings]

FIG. 1 is a front view of a split member that constitutes a pulley assembly according to the present invention.

FIG. 2 is a cross-sectional view of a pulley assembly in which the split members shown in FIG. 1 are fitted to face each other.

FIG. 3 is a front view of one of the split members that constitutes the pulley assembly of the second example according to the present invention.

FIG. 4 is a front view of the other split member of the second example used in combination with the split member of FIG. 3;

FIG. 5 is a cross-sectional view of a third example pulley assembly according to the present invention.

FIG. 6 is a sectional view of a fourth example pulley assembly according to the present invention.

FIG. 7 is a side view of an example pulley according to the related art.

8 is a front view of relevant parts for explaining a divided mold forming the pulley of the example of the related art shown in FIG. 7. FIG.

FIG. 9 is a cross-sectional view of another example of a prior art pulley assembly.

10 is a front view of the prior art example shown in FIG. 9. FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Divided member 2,2 'Cylindrical part 3,3' Tsuba 4 Shaft hole 4-1 Cylindrical part of shaft hole 5 Rib 5-1 Rib tip projection 5-2 Rib tip recess 6 Inlay part 7 Hold the rib Parallel projections 8 4 Molds divided into 4 9 Asymmetrical fitting parts 10, 11, 12, 13 Separate division members

Claims (7)

[Claims] 1. A pulley assembly, which is formed as an assembly of split members because the collars are provided on both sides, wherein the split members have shaft fitting holes of substantially the same size, and the flange portion and the collar portion A cylindrical portion extending from one surface in the axial direction, a rib on the inner peripheral surface of the cylindrical portion, and a coupling projection and a recess integrally formed at the tip of the rib are provided, and the projection and the recess are coupled to each other. A pulley assembly, which has a symmetrical arrangement and is formed as a pulley with flanges on both sides by fitting projections and recesses of the dividing member. 2. A pulley assembly, which is formed as an assembly of split members because the collars are provided on both sides, wherein the split members have shaft fitting holes of substantially the same size, and the flange portion and the collar portion Cylindrical parts with different lengths that extend in the axial direction from one surface,
A rib on the inner peripheral surface of the cylindrical portion, and a coupling projection and a recess integrally formed at the tip of the rib are provided, and the projection and the recess are symmetrically arranged so as to be opposed to each other, and the projection of the dividing member is provided. And a pulley assembly formed on both sides by fitting the recess into the pulley assembly. 3. The pulley assembly according to claim 1, wherein the protrusions and the recesses integrally formed at the tips of the ribs are alternately formed in the circumferential direction. 4. A pulley assembly, which is formed as an assembly of split members because the collars are provided on both sides, wherein the split members have shaft fitting holes of substantially the same size, one of which has a collar portion and the collar portion. A cylindrical portion extending in the axial direction from one side and a rib on the inner peripheral surface of the cylindrical portion, and the other side is opposed to the rib portion and the spigot portion on one side of the collar portion and the rib of the one split member, and sandwiches the rib. A pulley assembly, comprising parallel protrusions, wherein the protrusions and the ribs of the one split member are fitted to each other to form a pulley with a collar on both sides. 5. A pulley assembly having a difference in diameter formed by axially connecting separate members that are independent of each other, wherein the separating members have shaft fitting holes of substantially the same size, and one of the dividing members is a collar. Portion and a cylindrical portion axially extending from one surface of the flange portion, a rib on the inner peripheral surface of the cylindrical portion, and a coupling projection and a concave portion integrated with the tip of the rib, and the other split member is the projection and the concave portion. The pulley assembly is provided with a concave portion and a protrusion corresponding to, and the pulley assembly is formed by fitting the both. 6. The pulley assembly according to claim 1, wherein the outer peripheral surface of the cylindrical portion is provided with unevenness for driving the timing belt. 7. The pulley assembly according to claim 1, wherein the split members are integrally press-fitted and fixed to the shaft member in a state where the split members are fitted and positioned with respect to each other.