JP2000085934A - Conveyor belt, and its joining method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the degradation in joining strength of a joining part and improve the joining workability by setting the side part of a finger in a finger joint to be parallel to a conveyor belt in the longitudinal direction. SOLUTION: Firstly, layers (reinforcing cloths 4, 4', cover rubber 5, 5', etc.), other than a core canvas 1 are peeled and removed from a joining end part, and the joining end part of the core canvas 1 is cut into a plurality of fingers 16 whose side parts 6 are parallel to a conveyor belt body 15 in the longitudinal direction by a punching die, etc. Other joining end part to be joined is similarly punched into a plurality of fingers 16 and butted to be joined with each other. The fingers 16 at both end parts are punched in a corresponding manner. In the joined conveyor belt, the side part 6 of the fingers 16 is parallel to warps of the core canvas 1, i.e., the conveyor belt body 15 in the longitudinal direction, and the warps of the core canvas 1 are not broken at the side part 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an individual device (conveyor) to be used after a conveyor belt body having a single layer of a core body canvas as a tensile body is formed into a continuous belt-shaped body having a predetermined length. The present invention relates to a conveyor belt joined in a ring shape (also referred to as endless) in accordance with an apparatus and a joining method thereof. In particular, when the core body canvas made of synthetic fiber is designed to have a large warp and a small number of wefts, a conveyor belt having good joining efficiency (referred to as "tensile strength of a joint portion / tensile strength of a main body portion") can be obtained and joining work can be performed. (Also called endless work) can be made more efficient.

In a normal endless operation of a rubber conveyor belt, a conveyor belt body formed and vulcanized in a belt shape is cut into a predetermined length (a length designed according to a model), and a joining end portion thereof is formed as a core. After peeling off the body canvas and other parts, and temporarily joining the tip of the core body canvas according to a predetermined joining method, necessary reinforcing cloth, unvulcanized cover rubber, etc. are laminated and pressurized and heated. And vulcanize.

[0003]

2. Description of the Related Art Conventional means for joining a conveyor belt having a single-layer tensile member are, for example, an overlap method in which the joints are overlapped and joined, or a method in which the end of the tensile member is cut into a wedge type and butted. There is a lightning joint method for joining. As shown in FIG. 2, the lightning joint method
One end of the core body canvas 1 is punched into the lightning finger 11, and the other end is punched and butted into a shape corresponding to the lightning finger 11. In this state, unvulcanized adhesive rubbers 3, 3 ', reinforcing cloths 4, 4', and unvulcanized cover rubbers 5, 5 'separately prepared are laminated, and pressurized and heated from the upper and lower surfaces thereof to perform vulcanization. Bond with sulfuric acid.

[0004]

However, in the above-mentioned overlap system, the joining portion becomes thicker than the main body portion because the tensile members are overlapped, and the cleaning device (the transported object attached to the conveyor belt is moved on the tip drum by the cleaning device). Scraping device), there is a problem that adjustment of the scraping blade becomes difficult.

[0005] In the lightning-type joint system, there is a risk of peeling at the butted portion. In other words, the tip of the finger not only exerts the most force, but also the warp of the core body canvas is cut obliquely and buried, so that the cross section of the warp yarn that has not been subjected to the adhesive treatment is exposed, and that part is exposed. And the tensile strength of the joint decreases. As a countermeasure, there is a measure to apply an adhesive to the exposed cross section or to improve the compounding of the adhesive rubber so that the adhesive strength at the peripheral portion is increased, but the workability is deteriorated and the properties of the adhesive rubber are deteriorated. There is.

[0006] In addition, the core canvas, which is generally used as a tensile member, often has a thick warp and a thin weft. There is a problem that the width becomes smaller toward the part, the weft is detached and the warp tends to be separated, and the joining operation requires a long time. This tendency is particularly strong when the warp is a synthetic fiber.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to provide a conveyor belt which has a small reduction in bonding strength at a bonding portion and has good bonding workability and a bonding method thereof.

[0008]

According to a first aspect of the present invention, there is provided a conveyor belt according to the first aspect of the present invention, wherein the heart-body canvas joined by a finger joint method is a single layer. The sides of the fingers of the joint are parallel to the length of the conveyor belt.

Here, the finger means a plurality of protruding portions formed by punching the joining end of the conveyor belt main body into a comb blade shape. A finger joint is so called because it is joined with the fingers of both hands butted together. The fingers of the conveyor belt of the present invention are substantially rectangular (also referred to as a strip type), and the side portions (referred to as the long sides of the strip shape) are parallel to the length direction of the conveyor belt, that is, the warp yarns. Its tip is cut into a semi-circle,
The other end (base end) is continuous with the core body canvas of the main body. It should be noted that the space between these fingers and the adjacent finger is punched in a shape corresponding to the finger, and can be closely butted (with no gap) with the finger at the other joint end that has been punched in the same manner. . As described above, the warp of the core body canvas of the finger is not cut at the side of the finger, so that the tensile strength at this portion is hardly reduced. Also, since the strip is cut into a strip with a predetermined width, the weft is held up to the vicinity of the end, and the warp does not fall apart, and the joint work becomes easy.

According to a second aspect of the present invention, the width of the finger portion is 50 mm or more and 5% or more and 15% or less of the width of the conveyor belt body. The core body canvas usually has a thickness of 0.5 to 2 mm, and if the width of the finger portion is not more than 50 mm corresponding to this thickness, twisting occurs at the time of molding and the joining work becomes difficult. Also, even if the width of the fingers is less than 5% of the width of the conveyor belt, the joining operation is similarly difficult. If the width exceeds 15%, the number of fingers is too small, and the joining effect between the side portions of the joining portion is reduced. It does not appear, and the problem arises that the joining force at the tip of the finger is too low. The conveyor belt according to claim 3, wherein when the length (indicated by L) of the side portion of the finger is expressed in millimeters, L = "Nominal of belt strength" (N / mm) x (0. 45-1).

When the value (N / mm) (also referred to as the belt strength value) of the "nominal of belt strength" increases, the length of the finger needs to be increased in accordance with the belt strength value.
However, if it is less than 45% of the belt strength value, the joining strength becomes insufficient, causing peeling and cutting. If it exceeds 100%, the fingers are too long and the joining operation becomes difficult.

In a conveyor belt according to a fourth aspect of the present invention, the tips of the fingers are formed in a substantially semicircular shape. Since both the warp and the weft are cut at the tip, if the tip is cut at an acute angle, the tension may be partially concentrated and the bonding strength may be reduced. Therefore, it is preferable that the tip portion be a semicircle having no acute angle portion.

[0013] In the conveyor belt according to the fifth aspect, the core body canvas is made of synthetic fiber. Polyester heart and body canvas,
In the case of a synthetic fiber such as nylon, the effect of setting the finger shape to the shape of claims 1 to 4 is greatly exhibited. This is because synthetic fibers have a smaller coefficient of friction between the warp and the weft than natural fibers, and are more likely to fray the warp during the joining operation.

According to a sixth aspect of the present invention, a line (referred to as a joining line) connecting the tips of the fingers of the core body canvas is inclined with respect to the width direction of the conveyor belt.
Since the warp is cut at the tip of the finger and the joining force is reduced at that portion, the tip positions of the fingers are dispersed in the length direction of the conveyor belt to disperse the portion where the joining force is reduced. In addition, it is possible to minimize a decrease in the bonding force as a whole. Also, while the conveyor belt is bent by the pulley portion while traveling by the actual machine, if the joining line is parallel to the width direction of the belt, the entire joining line is simultaneously bent, but if it is inclined, it is sequentially bent. This has a favorable effect on maintaining the joining force.

According to a seventh aspect of the present invention, there is provided a method for joining a conveyor belt comprising a single-layered core body canvas by a finger joint method, wherein an adhesive rubber layer and a reinforcing cloth are provided on both sides of the core body canvas. To form a conveyor belt body in which cover rubber is laminated and vulcanized on both sides thereof, and the layers other than the core body canvas at the joining end are peeled off and removed, and the core body canvas is removed from the side edges. Punches into a plurality of fingers parallel to each other in the length direction of the conveyor belt body,
Abutted with the other joint end punched in the shape corresponding to this finger, temporarily bonded an unvulcanized rubber sheet to the upper and lower surfaces of the joint, and laminated the reinforcing layer and unvulcanized cover rubber on both surfaces. Then, only the joint is pressurized and heated to perform vulcanization bonding.

First, a conveyor belt main body having a reinforcing cloth formed and vulcanized by a conventional method is manufactured, and a joint portion at an end thereof is peeled for each constituent member, and members other than the core body canvas are removed. When the vulcanized member is peeled, it is difficult to restore the performance of the original design by re-adhering when peeled. Also, by exposing only the core body canvas, punching of the finger is facilitated. Punch out the fingers at each end of the joint and butt together without any gaps. This is because the bonding strength is reduced by the void. An unvulcanized adhesive rubber sheet is temporarily bonded to the upper and lower surfaces of the joint, a new reinforcing layer is temporarily bonded to both surfaces thereof, and an unvulcanized cover rubber is laminated on the outer layer,
The joint is vulcanized by applying pressure and heat. By vulcanizing unvulcanized rubber from the beginning, a conveyor belt with high bonding strength without overvulcanization can be obtained.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a conveyor belt according to the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing a joint portion of a conveyor belt according to the present embodiment, in which a joint portion of a core body canvas 1 is exposed and a part thereof is omitted.

The conveyor belt body 15 is formed by laminating adhesive rubber layers 3, 3 'and reinforcing cloths 4, 4' on both sides of the core body canvas 1, and further laminating cover rubbers 5, 5 'on both sides thereof. It is manufactured in a strip shape. The end portions of the conveyor belt body 15 having a predetermined length are joined to form a conveyor belt having a designed machine-length ring shape. The procedure is as follows: First, layers other than the core body canvas 1 (reinforcement cloths 4, 4 ', cover rubbers 5, 5', etc.) are peeled and removed from the joint end to expose the joint end of the core body canvas 1, The joining end is cut into a plurality of fingers 16 whose side portions 6 are parallel to the length direction of the conveyor belt body 1 by, for example, a punching die. Other joining ends to be joined are also punched out into a plurality of fingers 16 and joined together by abutting each other. At this time, the fingers 16 at both ends are punched out so as to correspond to each other. This is for joining without gap when butted. An unvulcanized rubber sheet (not shown) is temporarily bonded to the upper and lower surfaces of the joint, and the reinforcing cloths 4, 4 'and unvulcanized cover rubbers 5, 5' are laminated on both surfaces (FIG. 1). Shows a state in which these are removed), and presses, heats, and vulcanizes and bonds the joint to form a ring-shaped conveyor belt.

In the conveyor belt of the present invention thus joined, the side portions 6 of the fingers 16 are parallel to the warp of the core canvas 1, that is, parallel to the length direction of the conveyor belt body 15. As described above, since the warp of the core body canvas 1 of the finger 16 is not cut at the side 6, the tensile strength of this portion is little reduced. Also, since the strip is cut into a strip with a predetermined width, the weft is held up to the vicinity of the end, and the warp does not fall apart, and the joint work becomes easy.

As an embodiment of the present invention, as shown in FIG. 1, there is shown a conveyor belt in which the fingers have a strip shape as shown in FIGS. 1 to 3, and a comparative example in which the joining portion is a conventional electro-light type shown in FIG. 2. The result of a bending test with No. 1 is shown. Example 2
Is a case where the adhesive force of the adhesive rubber is reduced, and Example 3 is a case where the length of the finger is shortened.

1) Characteristics of the Material 1. Structure of the core body canvas (common to Examples 1 to 3 and Comparative Example 1) Belt strength = 2200 Material = Aramid Warp = 1500d / 2 × 3 × 3, 26 / 5 cm weft = 420 d / 1, 6 threads / 5 cm thickness = 2 mm Conveyor belt body width (W) = 300 mm 2. Joining form Example 1 Example 2 Example 3 Comparative example 1 Finger shape Strip type Strip type Strip type Lightning type Finger length L 2000mm 2000mm 1000mm 2000mm Finger width w 50mm 50mm 50mm 50m
m

2) Bending test method A bending running tester developed by the applicant.

3) Test Results Example 1 Example 2 Example 3 Comparative Example 1 Adhesive force (N / mm) 16 11.8 16 16 Flexural test (10,000 times) 500 500 500 192 Result No abnormality Peeling signs

4) Examination of Results The first embodiment and the second embodiment are examples in which the adhesive force of the adhesive rubber is changed, and the shape of the finger 16 is the same. Example 3
Indicates a finger length L of 45% of the belt strength value. In Example 1, Example 3, and Comparative Example 1, only the shape of the finger 16 was changed while using the same adhesive rubber. In the example, no abnormality was observed in the bending test of about 2.5 times as large as that of the 1.92 million times in which the peeling-off occurred in the comparative example 1, and the examples 2 and 3 showed slight peeling. There were only signs.

Next, the test results of the conveyor belt in which the joining type is slightly changed will be described. In the first embodiment, the width w of the finger 16 is preferably 50 mm or more and 5 to 15% of the width W of the conveyor belt. The core body canvas 1 usually has a thickness of 0.5 to 2 mm, and if the width of the finger 16 is not more than 50 mm corresponding to this thickness, twisting occurs at the time of molding, the weft comes off, and the warp becomes scattered. The joining operation becomes difficult. In addition, finger 16
If the width w is less than 5% of the width W of the conveyor belt, the joining operation is similarly difficult. If the width w exceeds 15%, the number of fingers is reduced, and the distal end portions 7 of the fingers 16 having a weak joining force are widely continuous. , There is a risk of peeling from that portion. If the belt strength value increases, it is necessary to increase the length L of the side portion 6 in accordance with the belt strength value. If it is too short, the joining strength becomes insufficient, causing peeling and cutting, and if it is too long, the joining operation becomes difficult. The length L of the side portion 6 of the finger 16 when expressed in millimeters is L =
"Nominal of belt strength" value (N / mm) x (0.45-1)
Is preferable. For example, if the belt strength value is 1
000, and the length L of the side portion 6 is 450 to 100.
When it is 0 mm, the strength of the joint is about 85 to 95% of the strength of the belt body 15, but is about 28% at 230 mm. When the length L of the side portion 6 exceeds 1000 mm, the joining operation is difficult because the finger portion 2 is too long. The tip 7 of the finger 16 is preferably formed in a substantially semicircular shape. Since both the warp and the weft are cut at the tip 7, if the tip 7 is cut at an acute angle, the tension may be partially concentrated and the bonding strength may be reduced. It is preferable to use a semicircular shape having a predetermined shape. When the core body canvas 1 is a synthetic fiber such as polyester fiber, for example, polyester or nylon, the entanglement between the warp and the weft is weak and fraying is likely to occur. The effect of specifying is more clear. It is preferable that a line (joining line) connecting the tips of the fingers 16 of the core canvas is inclined by an angle θ with respect to the width direction W of the conveyor belt body 15. By dispersing the tip positions of the fingers 16 in the length direction of the conveyor belt, a decrease in the joining force at the joining portion is prevented. θ
Is 17 °, the joining force is improved by 5 to 10% as compared with θ = 0. Further, by providing such an inclination, when the vehicle is run as a conveyor and bent by the pulley portion, the tips of the fingers are bent in the order of inclination, so that stress concentration is avoided, and the results in the following Table A are obtained. Was. The test conditions were as follows: belt strength value = 2200, belt width =
300mm, pulley diameter = 500mm, finger width = 50m
m, finger length = 1000 mm, and an in-house bending running tester was used.

[0026]

In the embodiment 4 inclined in this manner, the joining efficiency (the strength of the joining portion with respect to the strength of the belt body) is increased by 8% as compared with the comparative example 2 in which the inclination is not inclined, and even if the number of times of bending is increased. No tip peeling occurred.

[0028]

As is apparent from the above description,
The conveyor belt and the joining method according to the present invention have the following excellent effects.

In the conveyor belt according to the first aspect of the present invention, the side portions of the fingers are made parallel to the length direction of the conveyor belt, so that the joint portion has a small elongation and peels off even when repeatedly bent. Nothing. In addition, there is little fraying in the joining operation, and the joining is easy.

In the conveyor belt according to the second aspect of the present invention, a lower limit (50 mm or more, 5% or more of the belt width) is set for the finger width to prevent the weft from coming off and the warp from being frayed during the joining operation. Upper limit of finger width (15
% Or less) prevents a decrease in bonding strength.

In the conveyor belt according to the third aspect, the length of the finger portion is specified within a predetermined range in relation to the belt strength value, so that the strength of the joining portion changes with the change in the belt strength value. And the workability can be optimally designed.

In the conveyor belt according to the fourth aspect, since the tips of the fingers have a semicircular shape, the concentration of stress at the tips is minimized, and problems such as separation of the joints can be reduced.

[0033] In the conveyor belt according to the fifth aspect, the core body canvas is made of synthetic fiber. The shape of the above finger, etc.
The effect is most exhibited when the core body canvas is a synthetic fiber.

In the conveyor belt according to the sixth aspect, the line connecting the finger tips is inclined with respect to the width direction of the conveyor belt, so that the decrease in tensile strength due to the cutting of the warp at the tip part can be reduced. it can.

The method for joining conveyor belts according to claim 7 shows the most efficient and safe procedure for manufacturing the conveyor belt.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a joining portion of a conveyor belt according to an embodiment of the present invention, in which a joining portion of a core body canvas is exposed and a part thereof is omitted.

FIG. 2 is a perspective view showing a joining portion of a conveyor belt according to a conventional joining method, in which a joining portion of a core body canvas is exposed and a part thereof is omitted.

[Explanation of symbols]

 1: Heart body canvas 3, 3 ': Adhesive rubber layer 4, 4': Reinforcement cloth 5, 5 ': Cover rubber 6: Side part 7: Tip part 11: Lightning type finger 15: Conveyor belt body 16: Finger

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B29L 29:00 F term (Reference) 3F024 AA19 CA04 CA08 CA09 CB03 CB09 CB13 CB19 CB23 CB29 4F211 AA24 AA29 AA45 AD05 AD08 AD19 AD20 AG02 AG03 AG16 AH81 TA09 TC02 TC09 TC21 TD09 TD11 TD15 TH02 TH18 TN02 TQ04

Claims (7)

[Claims] 1. A conveyor belt in which a core body canvas joined by a finger joint system is a single layer, wherein side edges of fingers in the finger joint system are parallel to a length direction of the conveyor belt. A conveyor belt characterized by the following. 2. The width of the finger is 50 mm or more, and the width of the conveyor belt is 5% or more and 15% or more.
The conveyor belt according to claim 1, wherein: 3. The length of the side portion of the finger, when it is expressed in millimeters (mm), is 45% or more of the numerical value of “Nominal of belt strength” and is not more than the numerical value. Or the conveyor belt of 2. 4. The conveyor belt according to claim 1, wherein the tips of the fingers are formed in a substantially semicircular shape. 5. The heart body canvas is a synthetic fiber.
A conveyor belt according to any one of claims 1 to 4. 6. The conveyor belt according to claim 1, wherein a line connecting the tips of the fingers of the core canvas is inclined with respect to the width direction of the conveyor belt. 7. A method of joining a conveyor belt having a single layer of a core body canvas by a finger joint method, wherein an adhesive rubber layer and a reinforcing cloth are laminated on both sides of the core body canvas, and a cover rubber is further provided on both sides thereof. The conveyor belt body is manufactured by laminating and vulcanizing, the layers other than the core body canvas at the joining end are peeled and removed, and the side bodies are separated from each other in the longitudinal direction of the conveyor belt body. Punched into a plurality of fingers parallel to each other, butted against the other bonding end punched in a shape corresponding to this finger, and temporarily bonded unvulcanized rubber sheets to the upper and lower surfaces of the bonding portion, and the reinforcing layer A method of joining conveyor belts, comprising laminating unvulcanized cover rubbers, and pressurizing and heating the joints for vulcanization bonding.