WO2024053410A1

WO2024053410A1 - Wrapped joined v-belt

Info

Publication number: WO2024053410A1
Application number: PCT/JP2023/030452
Authority: WO
Inventors: 広大北野
Original assignee: バンドー化学株式会社
Priority date: 2022-09-06
Filing date: 2023-08-24
Publication date: 2024-03-14

Abstract

Provided is a wrapped joined V-belt (1) comprising a plurality of wrapped V-belt portions (2) joined together, on the back side thereof, with a tie band (40). The tie band (40) is formed by stacking a layer of rubber member having a thickness of from 0.5 to 2.0 mm inclusive, on a surface of cotton canvas of 90° plain weave or 120° wide-angle weave, chemical fiber blend canvas, or cord fabric canvas. The entire thickness of the tie band (40) is from 14.9 to 22% inclusive with respect to the entire thickness of the wrapped joined V-belt (1).

Description

Wrapped joint V-belt

The present invention relates to a wrapped V-belt in which the back sides of a plurality of wrapped V-belt parts are joined by a tie band.

Conventionally, a plurality of wrapped V-belt sections and tie bands are included, the outer peripheral surface of each wrapped V-belt section is connected by the tie band, and each wrapped V-belt section has a core layer including a core body; A wrapped joint comprising an elongated rubber layer laminated on the belt outer circumferential side of the core layer, a compressed rubber layer laminated on the belt inner circumference side of the core layer, and an outer cover fabric covering the entire outer surface of the belt. V-belts are known (for example, see Patent Document 1).

Patent No. 6577157

However, in conventional wrapped V-belts, the tie band is generally thin with an emphasis on flexibility, and as a result, the tie band may tear vertically due to falling into the pulley during running or malfunctioning when fitting with the pulley. There is a problem that this is likely to occur.

The present invention has been made in view of these points, and its purpose is to improve the vertical tear durability of a tie band.

In order to achieve the above object, in this invention, the structure of the tie band has been devised.

Specifically, the wrapped joint V-belt of the first invention includes a plurality of wrapped V-belt parts,
and a tie band that connects the back sides of the plurality of wrapped V-belt parts,
The tie band is
90° plain weave or 120° wide angle cotton canvas, chemical fiber blend canvas or sudare canvas;
A rubber member having a thickness of 0.5 mm or more and 2.0 mm or less, which is laminated on the surface of the cotton canvas, chemical fiber blend canvas, or sudare canvas,
The total thickness of the tie band is 14.9% or more and 22% or less of the total thickness of the wrapped V-belt.

In other words, if the total thickness of the tie band is less than 14.9% of the total thickness of the wrapped joint V-belt, vertical tearing will occur, and if it is greater than 22%, installation may be affected due to the layout. It may deteriorate or be damaged due to cracks in the tie band. However, according to the above configuration, even if the wrapped V-belt portion falls into the pulley during running, vertical tearing is less likely to occur due to the thicker tie band. Further, even if the fit with the pulley is poor, the rigidity of the tie band allows the shape to be maintained, leading to improved durability. Furthermore, since the tie band is made of an appropriately constructed cotton canvas, chemical fiber blend canvas, or sudare canvas and a rubber member, its effects are reliably exhibited.

In the second invention, in the first invention,
The thickness of the rubber member is 75% or more and 85% or less of the total thickness of the tie band.

In other words, if the thickness ratio of the rubber member is smaller than 75%, vertical tearing will occur, and if it is larger than 85%, the installation properties will deteriorate and cracks will easily occur in the tie band. However, with the above configuration, it is possible to maintain appropriate rigidity and prevent vertical tearing, and the back side is not too thick, so there are no problems with ease of installation or cracks in the tie band.

In the third invention, in the first or second invention,
Wrapped joint V-belt is
The overall width is 34 mm or more and 130 mm or less,
The overall thickness is 12 mm or more and 24 mm or less.

According to the above configuration, a wrapped V-belt with appropriate dimensions that does not cause longitudinal tearing can be obtained.

In a fourth invention, in any one of the first to third inventions,
The rubber member of the tie band is made of chloroprene rubber in which short fibers oriented in the belt width direction are at least one of cotton, PET, and aramid.

According to the above configuration, a tie band with appropriate rigidity, flexibility, and durability can be obtained.

As explained above, according to the present invention, by appropriately setting the structure and thickness of the tie band, it is possible to improve the vertical tear durability of the tie band.

FIG. 2 is an enlarged cross-sectional view of a wrapped V-belt. It is a flowchart showing the flow of belt production. It is a figure which shows the belt structure pattern of a comparative example and an example. FIG. 7 is another diagram showing belt configuration patterns of comparative examples and examples. FIG. 2 is a diagram schematically showing a durability test device. FIG. 3 is a cross-sectional view showing an enlarged cross-section of a pulley. It is a figure which shows the result of the durability test of a comparative example and an example. FIG. 7 is another diagram showing the results of durability tests of comparative examples and examples. FIG. 3 is a diagram showing test conditions in a monitor test on the market. FIG. 3 is a diagram showing a layout image in a monitor test in the market. It is a figure which shows the result of the monitor test in the market of a comparative example and an example. FIG. 2 is another diagram showing the results of a monitor test on the market for Comparative Examples and Examples. FIG. 3 is a diagram showing the ratio of the thickness of the tie band to the thickness of the entire wrapped V-belt. It is a figure showing the ratio of the thickness of a rubber member to the thickness of the whole tie band. It is a figure explaining the principle of vertical tearing and separation of a tie band, (a) is a conventional thing, (b) is a thing of this embodiment.

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

FIG. 1 is a cross-sectional view showing an exemplary wrapped V-belt 1 of the present embodiment. This wrapped joint V-belt 1 is suitable for use in, for example, piston pump crushers that are subject to pulsating loads, grinders that are subject to impact loads such as screens, crushers, hammer mills, reciprocating saws, chippers, etc., liquid stirrers that are used horizontally, and centrifugal separators. , mixers, etc. Further, the dimensions of the wrapped V-belt 1 are not particularly limited, but for example, the belt circumference is 1500 to 8500 mm, the belt width is 34 mm to 130 mm, and the belt thickness is 12 mm to 24 mm.

The wrapped combined V-belt 1 is made up of a plurality of wrapped V-belt sections 2 and tie bands 40 combined. In this embodiment, the number of wrapped V-belt sections 2 coupled to one wrapped V-belt 1 is not particularly limited. The shape of the wrapped V-belt portion 2 is standardized as M-type, A-type, B-type, C-type, and D-type as a general-use V-belt (JIS K 6233:2008).

The wrapped V-belt section 2 has a first adhesive rubber layer 12 and an elongated rubber layer 13 laminated on the upper part of the core wire 11, and a second adhesive rubber layer 14, a first compressed rubber layer 15, and a second adhesive rubber layer 14 on the lower part of the core wire 11. A compressed rubber layer 16 and a reinforcing layer 17 are laminated, and these laminated bands are covered with an outer covering canvas 18. The reinforcing layer 17 is, for example, a layered layer of multiple sheets of canvas. The core wire 11 is embedded between the first adhesive rubber layer 12 and the second adhesive rubber layer 14 so as to form a spiral having a pitch in the belt width direction.

The rubber composition constituting the first compressed rubber layer 15 and the second compressed rubber layer 16 includes a polymer component, a reinforcing material such as carbon black, a crosslinking agent, a co-crosslinking agent, a vulcanization accelerator, and a vulcanization accelerator. Consists of sulfur accelerator, anti-aging agent, softener, etc. This polymer component consists of natural rubber (NR), styrene-butadiene rubber (SBR), chloroprene rubber (CR), ethylene-α-olefin elastomer (EPDM), and the like. The polymer component may be composed of a single type, or may be composed of multiple types.

Furthermore, at least one surface of the outer covering canvas 18 may be coated with the rubber composition described above.

Next, the first adhesive rubber layer 12, the elongated rubber layer 13, and the second adhesive rubber layer 14 are configured in the shape of a band with a horizontally long rectangular cross section, and are uncrosslinked rubber components that are kneaded with various compounding agents mixed into the polymer component. It is formed from a rubber composition that is crosslinked with a crosslinking agent by heating and pressurizing the rubber composition.

The polymer components of the rubber compositions forming the first adhesive rubber layer 12, the elongated rubber layer 13, and the second adhesive rubber layer 14 are chloroprene rubber, chloroprene rubber, Examples include sulfonated polyethylene rubber (CSM), hydrogenated acrylonitrile rubber (H-NBR), and ethylene-α-olefin elastomer. The polymer component may be composed of a single type, or may be composed of multiple types.

As with the first compressed rubber layer 15 and the second compressed rubber layer 16, examples of compounding agents include reinforcing materials such as carbon black, vulcanization accelerators, crosslinking agents, anti-aging agents, softeners, and the like.

Further, the core wire 11 is made of twisted yarn such as polyester fiber (PET), polyethylene naphthalate fiber (PEN), aramid fiber, vinylon fiber, etc. In order to impart adhesiveness to the belt body 10, the core wire 11 is subjected to an adhesion treatment in which it is immersed in an RFL aqueous solution and then heated, and/or an adhesive treatment in which it is dipped in rubber glue and then dried, in order to impart adhesiveness to the belt body 10.

Further, the belt-forming fabric constituting the outer covering canvas 18 is made of, for example, a woven fabric, knitted fabric, non-woven fabric, etc. made of yarn such as cotton, polyamide fiber, polyester fiber, or aramid fiber. In order to impart adhesiveness to the belt body 10, the belt forming cloth is subjected to an adhesive treatment of being immersed in an RFL aqueous solution and heated before forming, and/or coated with rubber glue on the surface that will be the belt body 10 side. An adhesion treatment may be performed by drying the adhesive.

Furthermore, the rubber covering the belt-forming cloth may contain a friction coefficient reducing material. Examples of the friction coefficient reducing material include short fibers such as nylon staple fibers, vinylon staple fibers, aramid staple fibers, polyester staple fibers, and cotton staple fibers, and ultra-high molecular weight polyethylene resins.

The tie band canvas constituting the tie band 40 may be, for example, a cotton canvas, a chemical fiber blend canvas, woven at a 90° plain weave or a 120° wide angle, with a thickness of 0.5 mm or more and 0.7 mm or less. A tie band rubber member having a thickness of 0.5 mm or more and 2.0 mm or less is laminated on the surface of the sagging canvas. Note that the thickness of the tie band canvas may be thinner than 0.5 mm or thicker than 2.0 mm depending on the case.

The total thickness of the tie band 40 is 14.9% or more and 22% or less of the total thickness of the wrapped V-belt 1.

The tie band canvas (not shown), such as cotton canvas, chemical fiber blend canvas, or sudare canvas, is composed of woven fabric, knitted fabric, nonwoven fabric, etc. made of yarns such as cotton, polyamide fiber, polyester fiber, and aramid fiber. There is.

The tie band rubber member is made of chloroprene rubber, in which the short fibers oriented in the belt width direction are at least one of cotton, PET, and aramid.

(Method for manufacturing wrapped V-belt)
Hereinafter, a method for manufacturing the wrapped V-belt 1 of this embodiment will be briefly described with reference to FIG. 2.

First, each material constituting the wrapped V-belt 1 described above is prepared. These can be obtained by processing the uncrosslinked rubber composition described in the above embodiment into a sheet shape using a calender roll or the like. Further, the twisted yarn for the core wire 11, the belt forming fabric (not shown) for the outer covering canvas 18, and the tie band canvas are subjected to adhesive treatment by impregnation and/or coating.

Next, proceed to the center-body belt creation process. First, in the rubber layer forming step S01, a plurality of sheets of canvas that will become the reinforcing layer 17 are laminated on a mantle (not shown), and then a rubber sheet such as a chloroprene rubber composition for the second compressed rubber layer 16 is wrapped multiple times, A rubber sheet of the first compressed rubber layer 15 is wound thereon. Furthermore, a rubber sheet for the second adhesive rubber layer 14 is wound thereon. Furthermore, a core wire 11 such as a polyester cord coated with an adhesive is spirally wound thereon. Rubber sheets for the first adhesive rubber layer 12 and the elongated rubber layer 13 are wound thereon in order to produce a cylindrical laminated structure.

Next, in the width cutting step S02, the cylindrical laminated structure is sliced into a predetermined width on the mantle and then removed from the mantle.

Next, in a skiving step S03 (not shown), the annular laminated structure is wound between a pair of pulleys with the thick side of the rubber layer facing outward, and both edges are cut diagonally while rotating to form a V-shape. Skiving is performed to form a chamfer. This adjusts the volume.

Next, in the covering step S04, the outer periphery of the annular laminated structure is wrapped with a belt-forming cloth that will become the outer covering canvas 18.

Then, in the tie band step S05, a plurality of wrapped annular laminated structures are externally fitted into a cylindrical sheave having a V-groove (not shown), and a tie is placed on the outer surface of the plurality of laminated structures with adhesive rubber sandwiched between them. Tighten band 40.

Next, in a vulcanization step S06, the tie-banded laminated structure is placed in a cylindrical sheave having a V-groove and vulcanized using a press. In this way, the wrapped V-belt 1 is manufactured.

-Example-
Next, comparative examples and examples of the above-mentioned wrapped V-belt 1 will be explained.

As shown in FIG. 3, Comparative Example 1 has a tie band rubber with two layers of cotton canvas woven with cotton threads at a wide angle of 120 degrees and one layer of chloroprene rubber sheet with a thickness of 0.7 mm. A tie band 40 made of a material, an elongated rubber layer 13 made of a chloroprene rubber sheet containing staple fibers, a first adhesive rubber layer 12 made of a chloroprene rubber sheet, a core wire 11 made of aramid fiber, and a second adhesive rubber made of a chloroprene rubber sheet. Layer 14, a first compressed rubber layer 15 made of a chloroprene rubber sheet containing short fibers, a second compressed rubber layer 16 made of a chloroprene rubber sheet, a reinforcing layer 17 made of a wide-angle woven canvas of cotton threads and nylon threads, and a wide-angle woven canvas of cotton threads. It is composed of an outer covering canvas 18 made of canvas. Note that Comparative Example 1 is equivalent to the conventional product. Comparative Examples 2 to 4 below were specially prepared for comparison.

Comparative Example 2 differs from Comparative Example 1 in that the tie band 40 includes one layer of the same cotton canvas as Comparative Example 1 and two layers of tie band rubber members of a 0.7 mm thick chloroprene rubber sheet.

Comparative Example 3 differs from Comparative Example 1 in that the tie band 40 includes one layer of the same cotton canvas as Comparative Example 1 and five layers of tie band rubber members of a 0.7 mm thick chloroprene rubber sheet.

Comparative Example 4 differs from Comparative Example 1 in that the tie band 40 includes one layer of the same cotton canvas as Comparative Example 1 and six layers of tie band rubber members of a 0.7 mm thick chloroprene rubber sheet.

Example 1 differs from Comparative Example 1 in that the tie band 40 includes three layers of tie band rubber members, including one layer of the same cotton canvas as Comparative Example 1 and a 0.7 mm thick chloroprene rubber sheet.

Example 2 differs from Comparative Example 1 in that the tie band 40 includes one layer of the same cotton canvas as Comparative Example 1 and four layers of tie band rubber members of 0.7 mm thick chloroprene rubber sheet.

Due to these differences in configuration, as shown in FIG. The thickness increases to .2mm, 1.9mm, 2.6mm, 3.3mm, 4.0mm, and 4.7mm, and the ratio of the thickness of the rubber part to the total thickness of the tie band is 58.3% and 73% in the same order. .7%, 80.8%, 84.8%, 87.5%, and 89.4%.

In the case of a B-type wrapped V-belt with a pitch of 19 mm, the total thickness of the wrapped joint V-belt 1 is in the order of Comparative Example 1, Comparative Example 2, Example 1, Example 2, Comparative Example 3, and Comparative Example 4. The thickness increases to 13.0mm, 13.7mm, 14.4mm, 15.1mm, 15.8mm, and 16.5mm, and the ratio of the belt total thickness to the tie band total thickness is 9.2% and 13% in the same order. .9%, 18.1%, 21.9%, 25.3%, and 28.5%.

When the pitch is 25.5 mm for a C-type wrapped V-belt, the total thickness of the wrapped joint V-belt 1 is as follows: They are 16.0 mm, 16.7 mm, 17.4 mm, 18.1 mm, 18.8 mm, and 19.5 mm in order, and the ratio of the belt total thickness to the tie band total thickness is 7.5% and 11 in the same order. .4%, 14.9%, 18.2%, 21.3%, and 24.1%.

(Dynamic belt evaluation)
A durability test of the wrapped V-belt 1 will be described below. Here, as a test machine, wrapped coupling V-belts 1 of Comparative Examples 1 to 4 and Examples 1 and 2 were applied to a driving pulley DR having a diameter of 111 mm and a driven pulley DN having an outer diameter of 111 mm as shown in FIG. , while applying a load F of 200 kgf and rotating at 1800 rpm without any load. FIG. 6 shows an enlarged cross section of the B-type driving pulley DR and driven pool DN. The sample length of Comparative Examples 1 to 5 and Examples 1 and 2 was 3000 mm at a room temperature of 23 (-3 to +7)°C.

As shown in FIG. 6, the pitch between the wrapped V-belt parts 2, which is normally 19 mm, is increased to 19.6 mm to intentionally create a state of malfitting with the pulleys.

As shown in FIG. 7, in Examples 1 and 2 and Comparative Example 3, no vertical tear occurred, but in Comparative Example 4, although no vertical tear occurred, the tie band 40 was damaged due to cracks. . Further, vertical tearing occurred in Comparative Example 1 and Comparative Example 2.

As shown in FIG. 8, as a result of the durability test, longitudinal tearing occurred in Comparative Example 1 before 100 hours. Furthermore, in Comparative Example 4, it was found that because the tie band 40 was made too thick, the tensile strain on the canvas increased during normal bending, leading to cracks in the tie band. In addition, in Comparative Example 2, no vertical tearing occurred after 200 hours.

As described above, when the thickness of the rubber member of the tie band 40 becomes thicker, the force that expands the pitch of the wrapped V-belt is relaxed, which is effective in suppressing the occurrence of longitudinal tearing.

Below, a monitor test on the market of the wrapped V-belt 1 will be explained. As shown in Figures 9 and 10, a wrapped V-belt 1 consisting of four B-type V-belts with a length of 2692 mm joined together with tie bands was attached to the drive pulley DR' and driven pulley DN' of a combine harvester as an attachment machine. . The driving pulley DR' has a pulley diameter of 400 mm, and the driven pulley DN' has a pulley diameter of 320 mm. The wheat was harvested using a combine hydraulic pump with a maximum horsepower of 267 PS. The required life is 400 hours or more.

As shown in FIG. 11, in the market monitor test, Examples 1 and 2 satisfied customer requirements, but Comparative Examples 1 and 2 suffered vertical tearing, and Comparative Examples 3 and 4 showed poor installation. Due to difficulties, a monitor test was not possible.

As shown in FIG. 12, in the monitor test, vertical tearing occurred in Comparative Example 1 within 100 hours of the first stage. In Comparative Example 2, in which the tie band was relatively thin, a problem occurred at 400 hours in the second period. In Examples 1 and 2, no vertical tearing or tie band cracking occurred even after running for more than 400 hours in the second period, and there were no problems with attachability. As mentioned above, in Comparative Examples 3 and 4, the belt thickness was too thick and some interference with the machine components occurred, so that testing could not be performed. In other words, it was found that the mountability was poor. In Comparative Example 2, there was no complete vertical tearing, but signs of vertical tearing were observed.

To summarize the above experimental results, as shown in FIG. 13 and FIG. The total thickness of type B and type C is as high as 14.9% or more and 22% or less.

Similarly, in Examples 1 and 2, the thickness of the rubber member is as high as 75% or more and 85% or less of the total thickness of the tie band 40 in the B type and C type, compared to the conventional comparative example 1. It is.

(Principle of vertical tearing and separation of tie bands)
As shown in FIG. 15(a), vertical tearing or separation of the tie band 40 occurs when the tie band 40, especially the canvas 40a, is repeatedly subjected to tension between W2 and W2' due to pitch deviation of the V groove of the pulley. It is thought that it will become and destroy it. When the pitch deviation is 0 mm and W2=W2', vertical tearing is unlikely to occur, and the bottom crack of the wrapped V-belt portion 2 ends its life. Even if the pulley groove pitch tolerance is within the standard, if the pitch deviation of the V-groove of the pulley is large, the lifespan leading to longitudinal tearing will be shortened. In this embodiment, as shown in FIG. 15(b), in order to reduce the distortion (stress) of the canvas 40a due to the pitch deviation of the pulley V groove, a cushion rubber with low elasticity is installed between the canvas 40a and the wrapped V-belt section 2. By arranging the rubber part 40b) and raising the position of the canvas 40a, the shear angle β is reduced, and the low elasticity rubber (rubber part 40b) absorbs the shear strain stress, thereby reducing the strain stress applied to the canvas 40a. We are trying to increase the lifespan of vertical tearing.

Therefore, according to the method for manufacturing the wrapped V-belt 1 according to the present embodiment, by appropriately setting the configuration and thickness of the tie band 40, the vertical tear durability of the tie band 40 can be improved.

Note that the above embodiments are essentially preferable examples, and are not intended to limit the scope of the present invention, its applications, or uses.

1 Wrapped joint V-belt 2 Wrapped V-belt section 10 Belt main body 11 Core wire 12 First adhesive rubber layer 13 Elongated rubber layer 14 Second adhesive rubber layer 15 First compressed rubber layer 16 Second compressed rubber layer 17 Reinforcement layer 18 Outer cover Canvas 40 Tie band 40a Canvas 40b Rubber part

Claims

Multiple wrapped V-belt parts,
and a tie band that connects the back sides of the plurality of wrapped V-belt parts,
The tie band is
90° plain weave or 120° wide angle cotton canvas, chemical fiber blend canvas or sudare canvas;
A rubber member having a thickness of 0.5 mm or more and 2.0 mm or less, which is laminated on the surface of the cotton canvas, chemical fiber blend canvas, or sudare canvas,
A wrapped V-belt, wherein the tie band has a total thickness of 14.9% or more and 22% or less of the total thickness of the wrapped V-belt.
The wrapped V-belt according to claim 1, wherein the thickness of the rubber member is 75% or more and 85% or less of the total thickness of the tie band.
The overall width is 34 mm or more and 130 mm or less,
The wrapped V-belt according to claim 1 or 2, characterized in that the overall thickness is 12 mm or more and 24 mm or less.
3. The rubber member of the tie band is characterized in that the short fiber material oriented in the belt width direction is chloroprene rubber that is at least one of cotton, PET, and aramid species. Wrapped joint V-belt.