KR20160127546A

KR20160127546A - Pulley having a slit

Info

Publication number: KR20160127546A
Application number: KR1020150059108A
Authority: KR
Inventors: 김병수; 음용진
Original assignee: (주)로보티즈
Priority date: 2015-04-27
Filing date: 2015-04-27
Publication date: 2016-11-04
Also published as: WO2016175556A1

Abstract

An embodiment of the present invention relates to a pulley having a slit, and more particularly, to a pulley having a slit, and more particularly, when a spindle part is inserted, a slit is added to a loosely and stiffly- The present invention relates to a pulley having a slit. According to a pulley having a slit according to an embodiment of the present invention, a space for shrinking and expanding the pulley can be formed to form a structure capable of shrinking and expanding during assembly and separation.

Description

{PULLEY HAVING A SLIT}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pulley having a slit, and more particularly, to a pulley having a slit by adding a slit to the pulley when the spindle part is inserted, To a pulley having an improved slit so as to have a suitable indentation strength.

Generally, in the belt conveyor used for transporting raw materials and materials, a hollow pulley is rotatably supported by a shaft, and a rubber is attached to the outer peripheral surface of the pulley. The rubber is provided to prevent slippage between the pulley and the conveyor belt driven by the pulley. The rubber is provided to prevent slippage between the rubber and the belt since it is formed in a plate shape and attached to the outer peripheral surface of the pulley. Since the rubber is formed in a plate shape and attached to the outer circumferential surface of the pulley, the rubber is worn by friction between the rubber and the belt, and the pulley must be frequently replaced due to wear of the rubber.

Also, due to the frequent exchange of pulleys, the cost of frequent replacement of the pulleys as well as the productivity has been consumed.

In addition, there is a problem that due to the rigidity of the pulley, even if the spindle is inserted into the hollow of the pulley, the spindle does not fit well.

Since the rubber is attached and used on the outer surface of the pulley in the prior art 10-0907186 (belt conveyor pulley), the rubber is worn by the friction between the rubber and the belt, there is a problem in that pulleys are frequently replaced due to abrasion of the rubber, resulting in a decrease in productivity and a cost of frequent replacement of the pulleys. As a result, a large number of slits A rubber having protrusions protruding outward through a slit and having a locking protrusion to be caught by the slit is provided. However, it is possible to control the degree of looseness and stiffness according to the dimensional deviation The level of pulleys is not being provided.

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention has been made to solve the above-mentioned problems occurring in the prior art, and it is an object of the present invention to provide a spindle- The present invention relates to a structure of a pulley capable of controlling a press-fitting strength by forming a slit and providing a tension between the slit and a center hole, and a pulley thus formed.

According to an aspect of the present invention, there is provided a pulley having a slit, comprising: a central hole formed in a cylindrical shape; First and second slits symmetrically formed in an arc shape between the center hole and an outer peripheral surface of the pulley and ribs protruding from an inner peripheral surface of a pulley formed at a position corresponding to the first and second slits, the pulley having a slit including a rib.

In an embodiment of the present invention, the distance between the first and second slits and the center hole may provide a pulley that is 1/10 to 1/2 of the diameter of the center hole.

In the embodiment of the present invention, the circumferential length of the first and second slits is 1/16 to 1/4 of the entire circumferential length passing through the center of the first and second slits, .

In the embodiment of the present invention, there is provided a pulley including third and fourth slits having the same length and the same shape at a position where the first and second slits are rotated by 90 degrees with respect to the center of the rotation axis of the pulley .

In the embodiment of the present invention, it is possible to provide a pulley that further includes holes having the same shape as the center hole to the right and left of the first and second slits.

In the embodiment of the present invention, it is possible to provide a pulley further including a pulley further including first and second ribs protruding radially inward of the center hole.

In an embodiment of the present invention, the first and second ribs may be disposed at the center of the first and second slits.

According to an embodiment of the present invention, a slit may be formed between a center hole and an outer peripheral surface of a pulley to adjust a press-fit strength according to a dimensional deviation, thereby improving a press-in strength of a spindle.

According to the structure of the pulley in which the slit is formed according to the embodiment of the present invention, a space for shrinkage and expansion is formed between the inner circumferential surface and the outer circumferential surface of the pulley to form a pulley structure capable of shrinking and relaxing when assembling and separating the pulley can do.

It should be understood that the effects of the present invention are not limited to the above effects and include all effects that can be deduced from the detailed description of the present invention or the configuration of the invention described in the claims.

1 is a perspective view showing the shape of a pulley before and after the improvement.
2 is a perspective view showing a structure of a pulley according to an embodiment of the present invention.
3 is a plan view of a pulley according to another embodiment of the present invention.
4 is a cross-sectional view of a pulley according to another embodiment of the present invention.
5 is a plan view of a pulley according to another embodiment of the present invention.
6 is a cross-sectional view of a pulley according to another embodiment of the present invention.
7 is a view showing an indentation load measuring apparatus according to an embodiment of the present invention.
8 is a graph showing experimental results of indentation load according to an embodiment of the present invention.
9 is a graph showing an experimental result of indentation load according to another embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described with reference to the accompanying drawings. However, the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

Throughout the specification, when a part is referred to as being "connected" to another part, it includes not only "directly connected" but also "indirectly connected" . Also, when an element is referred to as "comprising ", it means that it can include other elements, not excluding other elements unless specifically stated otherwise.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a perspective view showing the shape of a pulley before and after the improvement.

Referring to FIGS. 1 (a) to 1 (d), FIGS. 1 (a) and 1 (b) show the shape of a pulley having a small shape (hereinafter referred to as "pulley 100") before and after the improvement. 1 (c) and 1 (d) show the shape of the pulley having a large shape (hereinafter referred to as a "pulley", 200) before and after the improvement.

1 (a) to 1 (d), a central hole 120 formed in a cylindrical shape, first and second slits 121 and 122 formed symmetrically in an arc shape between the center hole 120 and the outer peripheral surface of the pulley, And ribs 122 and 124 protruding from the inner circumferential surface of a pulley formed at positions corresponding to the first and second slits 112 and 114 and the first and second slits 112 and 114.

And may further include first and second ribs protruding radially inward of the center hole.

The first and second ribs may be disposed at the centers of the first and second slits.

1 (a) and 1 (b), in the case of the small pulley 100, a hole 120 may be formed at the center. Grooves may be formed on the outer circumferential surface of the small pulley 100 at a central portion thereof. 1 (a) and 1 (b) can include a first outer peripheral portion 102 surrounding the center hole 120 and a second outer peripheral portion 104 surrounded by an outer peripheral surface.

The distance between the first and second slits and the center hole may be 1/10 to 1/2 of the diameter of the center hole 120. If the distance between the first and second slits 112 and 114 and the center hole 120 is less than 1/10 of the diameter of the center hole and the distance from the center hole 120 is close to the center hole 120, The first and second slits 112 and 114 formed in the pulley 100. 100A may be broken. If the distance between the first and second slits and the center hole is larger than 1/2 of the diameter of the center hole 120, the effect of reducing the press-fitting strength of the spindle 150 is reduced, The insertion and removal operations of the spindle 150 do not progress smoothly despite the insertion, and the workability may be deteriorated.

The circumferential length of the first and second slits may be 1/16 to 1/4 of the circumferential length of the first and second slits. If the length of the arc of the first and second slits 112 and 114 is less than 1/16, the effect of forming the slits 112 and 114 is insignificant and the effect of reducing the press-fitting strength of the spindle 150 may be reduced. When the length of the arc including the slits 112 and 114 is longer than 1/4 of the length of the arc including the slits 112 and 114, the distance between the first and second slits 112 and 114 and the center hole 120 is close to the center hole 120, Cracks may be generated between the first and second substrates 112 and 114 and may be damaged.

The ribs 122 and 124 are formed at positions corresponding to the first and second slits 112 and 114 and may be protruded from the inner circumferential surface of the pulleys 100 and 100A. The ribs 122 and 124 can prevent the pulleys 100 and 200 from being damaged due to the insertion of the spindle 150. For example, the ribs 122 and 124 may be formed of a material having elasticity.

Referring to FIGS. 1C and 1D, the same principle may be applied to the large pulley 100A. However, in the case of the large pulley 200, the first and second slits 112 and 114 may further include holes 132, 134, 136, and 138 having the same shape as the center hole 120 on the right and left sides. The holes 132, 134, 136, and 138 may be formed symmetrically with respect to the center hole 120. The holes 132, 134, 136, 138 may have the same shape and the same size.

2 is a perspective view showing a structure of a pulley according to an embodiment of the present invention.

Referring to Fig. 2, Fig. 2 (a) is a perspective view of the small pulley 100, and Fig. 2 (b) is a perspective view of the large pulley 100A.

In FIG. 2, a center hole 120 passing through the pulleys 100 and 100A and two circular arc-shaped first and second circular arc holes 120 and 100A formed between the center hole 120 and the outer peripheral surfaces of the pulleys 100 and 100A, The first and second slits 112 and 114 are formed at positions opposite to each other and have a structure capable of reducing the pressing force of the spindle 150 passing through the center hole 120 Lt; / RTI >

In the structure of the pulleys 100 and 100A forming the slits 112 and 114, first and second ribs 122 and 124 protruding from the center hole 120 are provided between the first and second slits 112 and 114, .

The thickness of the first outer circumferential portion 102 is smaller than the thickness of the second outer circumferential portion 104 between the first outer circumferential portion 102 surrounding the center hole 120 and the second outer circumferential portion 104 including the outer circumferential surface And the first and second slits 112 and 114 may be formed on the first outer circumferential surface of the first outer circumferential portion 102.

The first outer circumferential portion 102 may be less than 1/3 of the thickness of the second outer circumferential portion 104. If the thickness of the first outer circumferential portion 102 is large, the resistance force at the time of inserting the spindle 150 can be large. The first and second slits 112 and 114 are formed on the outer circumferential surface of the first outer circumferential portion 102 to increase flexibility.

3 is a plan view of a pulley according to another embodiment of the present invention.

Another embodiment of FIG. 3 may include four slits 112, 114, 116, 118 in the periphery of the central hole 120. The four slits 112, 114, 116, and 118 may be formed at equal intervals around one circumference. The center hole 120 may include ribs 122, 124, 126, and 128 for each slit. When a large number of slits 112, 114, 116, 118 are formed, the spindle 150 can be inserted with a smaller indentation strength. However, if the number of the slits 112, 114, 116, and 118 increases, the airflow increases, weakens to a moment / torque, and the risk of damage may increase.

Holes 132, 134, 136 and 138 formed in the same shape as the central hole 120 are formed in the second outer peripheral portion 104 of the large pulley 100A with the first and second slits 112 and 114 at the center May include.

As shown in FIG. 3, the pulley 100A has holes 132 formed in the same shape as the center hole 120 with the first and second slits 112 and 114 therebetween, even when there is no stepped pulley, , 134, 136, 138). The formation of the holes 132, 134, 136, and 138 may lower the indentation strength of the spindle 150. [

4 is a cross-sectional view of a pulley according to another embodiment of the present invention.

Referring to FIG. 4, a groove may be formed in a central portion of the outer circumferential surface. Without the slits 112, 114, 116, 118 surrounding the central hole 120, pressure may be applied to the shaft during extrusion, which may affect the shape of the product.

5 is a plan view of a pulley according to another embodiment of the present invention.

Referring to FIG. 5, the central hole 120 may be disposed at the center and four slits 112, 114, 116, and 118 may be formed. The four slits 112, 114, 116, and 118 may be formed at equal intervals on one circumference.

The inner circumferential surface 102 of the center hole 120 opposed to the slits 112, 114, 116 and 118 may include first, second, third and fourth ribs 122, 124, 126 and 128. Another embodiment of the present invention may be a small pulley with stepped pulleys.

6 is a cross-sectional view of a pulley according to another embodiment of the present invention.

Referring to FIG. 6, grooves G may be formed on the outer circumferential surface of the pulley 100.

And the second outer peripheral portion 104 may be formed on the right and left sides of the groove. The first outer peripheral portion 102 may be exposed to the outside.

{Experiment example}

7 is a view showing an indentation load measuring apparatus according to an embodiment of the present invention.

Referring to FIG. 7, when the small pulley 100 and the spindle 150 are engaged, the load applied to the push-pull stand, which is a push-in load measuring device, is measured by pushing the push-pull stand. And on the right side an enlarged view of the spindle 150 is shown.

FIGS. 8 and 9 are graphs showing the results of the indentation strength measurement according to an embodiment of the present invention.

The indentation strength is measured when the pulley 100, 100A and the spindle 150 are engaged and moved by a certain distance to the push-pull stand and press-fitted. 8 and 9, the X axis represents the displacement and the Y axis represents the load. Since the X-axis displacement represents the displacement of the spindle 150 with time, it can be said that the load on the left is the initial displacement and the load on the right is the load after the entry.

An indentation tester can be used to measure the indentation strength. As an example of the above-described indentation tester, a push-pull stand can be used.

The indentation strength can be measured by the following procedure. The motor is stable against external load and overload, and can use AC servomotor capable of precise control. With this configuration, it is possible to eliminate the risk factors such as external vibration in the field.

When the load sensor is press-fitted, a displacement proportional to the indentation load is generated, and according to the deformation, a strain gauge (not shown) built in the load sensor Can be changed. As a result of such a change in electric resistance, the current flowing eventually can change.

The indentation strength measurement experiment according to the embodiment of the present invention can calculate the load by inversely calculating the change of the current as described above by the change of the displacement. Such a result can be seen through a program built in an indentation tester (not shown), but detailed description will be omitted.

Referring to FIG. 8, it can be seen that the initial entry load of the small pulley 100 is lower than that of the conventional pulley, and the load is lowered again after the entry. FIG. 8A shows the degree of reduction of the load after entering the small pulley 100.

Referring to FIG. 9, it can be seen that, in the case of the large pulley 100A, the initial entry load is lower than that of the conventional pulley, and the load is lowered again after the entry.

In the case of the large pulley 100A, although not shown, it has been confirmed that when the conventional inserted spindle 150 is loose, the entry load is increased and improved. Such contents can be confirmed in the case of sample 4 in Table 1 below.

Table 1 below shows the maximum load values for each case of the small pulley and the large pulley.

Maximum load The small pulley (100) The large pulley 100A, Conventional Example Conventional Example Sample 1 27.7N 14.5N 22N 15.7N Sample 2 37.2 N 11.4 N 26.9 N 17.6N Sample 3 21N 12.2N 22.1 N 17.6N Sample 4 20.5N 14.2N 4.7N 15.6N Average 26.6N 13.1 N 19.0 N 16.6N

As can be seen in Table 1, in the case of the pulleys 100 and 100A, the load characteristics of the pulleys 100 and 100A are improved by reducing the indentation strength by adding the slits 112, 114, 116 and 118 .

It will be understood by those skilled in the art that the foregoing description of the present invention is for illustrative purposes only and that those of ordinary skill in the art can readily understand that various changes and modifications may be made without departing from the spirit or essential characteristics of the present invention. will be. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present invention.

100: Small pulley 102: First outer periphery
104: second outer circumferential portion 112: first slit
114: second slit 120: center hole
122: first rib 124: second rib
132: first hole, 134: second hole
136: third hole, 138: fourth hole
150: spindle 100A: large pulley

Claims

In a pulley having a slit,
A central hole formed in a cylindrical shape;
First and second slits formed symmetrically in an arc shape between the center hole and the outer peripheral surface of the pulley;
And a rib protruding from an inner peripheral surface of a pulley formed at a position corresponding to the first and second slits.

The method according to claim 1,
Wherein a distance between the first and second slits and the center hole is 1/10 to 1/2 of a diameter of the center hole.

The method according to claim 1,
Wherein the circumferential length of the first and second slits is 1/16 to 1/4 of the circumferential length of the first and second slits.

The method according to claim 1,
Further comprising third and fourth slits having the same length and the same shape at a position where the first and second slits are rotated by 90 degrees with respect to the center of the rotation axis of the pulley.

The method according to claim 1,
Further comprising a plurality of holes having the same shape as the center hole to the right and left sides of the first and second slits.

The method according to claim 1,
Further comprising first and second ribs protruding radially inward of the center hole.

The method according to claim 6,
Wherein the first and second ribs are disposed at the center of the first and second slits.