Flat drive belt and its manufacturing method

Abstract

FIELD: mechanical engineering.SUBSTANCE: flat drive belt comprises upper, middle, lower and traction layers. The top layer is made of synthetic fabric with a fine-mesh texture, comprising graphite particles and impregnated with an antifriction compound in a ratio of up to 15% by weight. The bottom layer comprises graphite particles. A method for manufacturing a flat drive belt is also claimed.EFFECT: belt efficiency is increased by improving its antistatic and friction properties.8 cl, 3 dwg

Description

[0001] The invention relates to the field of mechanical engineering, namely to devices that ensure the normal operation of machines, in particular to endless flat power drive belts.

[0002] A utility model “Drive belt” is known (patent RU 108523 F16G 1 / 00, published on September 20, 2011), containing an elastomer base with compression and tension layers, a tape cord made of rubberized fabric with power threads.

[0003] A disadvantage of this utility model is its low efficiency due to the belt profile shape, specifically, the V-belt of this model. V-belts are characterized by significant energy losses due to bending, as well as significant friction losses due to contact between the belt's side surfaces and the pulley surface. With constant contact, the friction between the belt's side surfaces and the pulley surface causes excessive belt heating, which contributes to belt deterioration and premature wear. The interaction of the V-belt's ribs with the pulley surface also contributes to excessive noise.

[0004] The invention “Drive belt” is known (patent RU 2397383 F16G 5 / 06 F16G 5 / 20 F16G 1 / 08, published on 20.08.2010), containing a base that includes an elastic material and has stretchable elements oriented in the longitudinal direction, wherein the base has a profiled part in contact with the pulley, containing a fibrous non-woven fabric made of acrylic fibers.

[0005] A disadvantage of this invention is its low efficiency, due to the belt's insufficient antistatic properties. Standards require belts to reduce surface resistance, i.e., to provide antistatic properties. In this invention, the drive belt is made of electrically insulating materials or materials with high resistance.

[0006] The invention “Drive belt” is known (patent RU 2253773 IPC F16G 1 / 08, F16G 1 / 28, F16G 5 / 06, F16G 5 / 20, published on 10.06.2005), containing an elastomeric base with tension and compression layers, made in the form of separate elements located on a cord layer, the twisted cords of the cord layer consist of threads independent of each other, the space between which is filled with elastomer.

[0007] A disadvantage of this invention is its low efficiency, due to the complexity of the manufacturing technology and, consequently, its high cost. It should also be noted that, as a rule, belts are electrically insulating or contain insulating materials. Standards may also specify requirements for belts to reduce surface resistance, i.e., to reduce their antistatic properties. In this invention, the drive belt is made of electrically insulating materials, which also contributes to reduced efficiency.

[0008] The invention “Drive belt” is known (patent RU 2248480 IPC F16G 1 / 28, F16G 5 / 00, published on March 20, 2005), containing a supporting layer, a stretching layer and a compression layer.

[0009] A disadvantage of this invention is its low efficiency, due to the belt's insufficient antistatic properties. Standards require belts to reduce surface resistance, i.e., to provide antistatic properties. In this invention, the drive belt is made of electrically insulating materials or materials with high resistance.

[0010] The invention “Belt made of wear-resistant antistatic fabric” is known (patent US 8192316 IPC F16G 1 / 04, published 03.02.2009), comprising a belt made of elastomeric material having a drive side and a back side, a stretching element and an antistatic, wear-resistant fabric made of synthetic polymer fiber with a silver metallic coating.

[0011] The disadvantage of this invention is its low efficiency, due to the high cost of the product due to the use of an expensive metal, namely silver, as a conductive component.

[0012] The invention “V-belt with a canvas-rubber complex and a method for manufacturing a V-belt” (patent US 5417619 IPC F16G 1 / 00, published 05.05.1994) is known, containing a V-belt made of an outer layer of canvas impregnated with rubber, a rubber layer made of a composition including conductive hydrocarbons.

[0013] The disadvantage of this invention is its low efficiency due to the insufficient wear resistance of the V-belt, which leads to the formation of conductive dust and, as a consequence, to the formation of an undesirable conductive layer of this dust on the devices of the mechanical system.

[0014] The invention "Belt transmission system and belt used in this system" is known (patent RU2507424 F16H 7 / 02, F16H 7 / 18, F16H 55 / 36, F16G 1 / 08, F16G 1 / 28, F16G 5 / 20, published on 20.02.2014), selected as a prototype and containing a driving and driven pulleys having annular grooves on the working surface, an endless belt consisting of a thin layer of rubber, a layer of rubber with adhesive properties, a thick layer of rubber made in the form of longitudinal protrusions on the outer surface of the belt, and a cord made of aramid or polyester threads.

[0015] A disadvantage of this invention is its low efficiency, due to the belt's insufficient antistatic and friction properties. Standards require belts to reduce surface resistance, i.e., to provide antistatic properties. In this invention, the drive belt is made of electrically insulating materials or materials with high resistance. It should also be noted that this belt has trapezoidal protrusions on its outer surface. As a result, during operation, when it bends around the pulley, tension and compression cycles occur. This can lead to heating and separation of the thick rubber layer from the adhesive rubber layer, reducing the belt's durability. The trapezoidal shape of the protrusions on the outer surface contributes to increased noise levels during operation.The working surface of a thin rubber layer has an insufficient coefficient of friction, which increases the likelihood of belt slippage on the pulley, resulting in reduced belt transmission efficiency. Cords made of longitudinally arranged aramid or polyester fibers are arranged parallel to each other and connected by a rubber layer. Rubber has lower strength than aramid or polyester, so increasing the belt tension can lead to increased distance between the cords. As the rubber layer wears, longitudinal delamination (or localized longitudinal ruptures) can occur, reducing belt reliability. Another disadvantage of this belt is the use of rubber in all belt layers, due to its relatively heavy weight, insufficient heat resistance, and excessive hardness at low temperatures. Rubber also requires additional manufacturing operations (vulcanization).

[0016] The purpose of the declared technical solution is to eliminate the above-mentioned shortcomings.

[0017] The technical result of the invention is to increase the efficiency of a flat drive belt by improving its antistatic and frictional properties.

[0018] The technical result is achieved in that in a flat drive belt containing an upper layer, a middle layer, a lower layer and a traction layer, the upper layer is made of synthetic fabric impregnated with an antifriction composition, in a ratio of, wt. %, up to 15% of the composition.

[0019] The top layer is made of synthetic fabric with a fine-mesh texture.

[0020] The top layer is made of synthetic fabric containing carbon threads and graphite particles.

[0021] The middle layer is made of thermoplastic in a ratio of, wt. %, up to 55% of the composition.

[0022] The bottom layer is made of NBC synthetic rubber with the addition of carbon black and silicon fillers.

[0023] The bottom layer has micro ribs.

[0024] The bottom layer is made of NBR synthetic rubber with the addition of graphite particles in a ratio of 10-15% by weight of the composition.

[0025] The traction layer is made in the form of a polyester cord in a ratio of up to 15% by weight of a composition made of high-strength polyester fibers woven into a dense mesh.

[0026] The manufacturing method consists of implementing the following sequence of actions.

[0027] At the first stage, a traction layer is produced in the form of a polyester cord, and using automated machines, a cord of the required width and length is woven from polyester threads.

[0028] In the second stage, the middle layer is made, and during the manufacturing process, a cord of polyester fibers, produced on automated machines, is placed into the mold with thermoplastic, and then pressed.

[0029] At the third stage, the bottom layer is formed, while the prepared synthetic rubber NBR with impurities (carbon black, silicon fillers and graphite particles) is applied to the previously obtained traction and middle layers using the extrusion method and is vulcanized in press molds at a temperature of 180°C.

[0030] At the fourth stage, the top layer made of synthetic fabric is applied, during which the synthetic fabric is glued with epoxy adhesive to the previously made traction, middle, and bottom layers, after which the synthetic fabric is heat treated.

[0031] The proposed technical solution is illustrated in Fig. 1, which shows a general view of a flat drive belt, in Fig. 2, which shows a flat drive belt in section, in Fig. 3, which shows an algorithm for implementing a method for manufacturing a flat drive belt.

[0032] The flat drive belt consists of the top layer 1, the middle layer 2, the bottom layer 3 and the traction layer 4.

[0033] The top layer 1 is made of synthetic fabric impregnated with an antifriction composition in a ratio of up to 15% by weight of the composition and having a fine-mesh texture, while the synthetic fabric contains carbon threads and graphite particles.

[0034] Underneath the top layer 1 is a middle layer 2 made of thermoplastic in a ratio of up to 55% by weight. The use of thermoplastic reduces the product's weight, extends the operating temperature range (without affecting the product's performance properties), and eliminates additional manufacturing steps.

[0035] Below middle layer 2 is traction layer 4, made of polyester cord with a composition ratio of up to 15% by weight, composed of high-strength polyester fibers woven into a dense mesh, ensuring consistent longitudinal and transverse alignment of the polyester fibers. The use of a dense mesh eliminates the possibility of belt delamination in the longitudinal direction during operation, thereby increasing belt reliability.

[0036] Below traction layer 4 is a bottom layer 3 made of NBR synthetic rubber with added carbon black and silicon fillers and featuring micro-fins to ensure efficient heat transfer. Graphite particles are also added to the bottom layer at a ratio of 10-15% by weight.

[0037] The flat drive belt operates as follows. The flat drive belt is mounted in a mechanical system so that the drive pulley contacts the top layer 1, made of synthetic fabric. Thanks to its anti-friction coating and fine-mesh texture, the top layer 1 of the flat drive belt has a high coefficient of friction, preventing belt slippage during load changes.

[0038] Bottom layer 3 contacts the driven pulley, transmitting torque. Bottom layer 3 features micro-ribs that increase the surface area, ensuring efficient heat transfer and preventing belt overheating, thereby extending its service life.

[0039] Traction layer 4, made of polyester cord, bears the main tensile force. Thanks to the use of high-strength polyester fibers, the traction layer has high strength and minimal elongation (less than 1%), ensuring stable belt geometry, preventing sagging and shifting. Length retention is ensured even under prolonged cyclic loads, which is especially important for high-precision equipment. The weaving of polyester fibers into a dense mesh ensures consistent longitudinal and transverse alignment of the polyester fibers, eliminating the possibility of belt delamination in the longitudinal direction during operation, thereby increasing belt reliability.

[0040] As the load increases, traction layer 4 evenly distributes the load across the entire width of the belt, which prevents local overloads and helps to increase the service life of the belt.

[0041] Middle layer 2, made of thermoplastic, provides sufficient elasticity and flexibility of the belt and also absorbs shock loads and vibrations during operation, protecting the mechanical system from premature failure and wear.

[0042] The elasticity of all layers allows the belt to adapt to minor pulley misalignments without loss of efficiency.

[0043] The use of a synthetic fabric impregnated with an anti-friction compound in the top layer 1 improves abrasion resistance, increasing the service life of the top layer 1. The use of NBC synthetic rubber in the bottom layer 3, which is resistant to moisture, oils and temperature changes, allows the belt to be used in aggressive environments.

[0044] The addition of graphite particles to the top layer 1 and bottom layer 3 helps dissipate static electricity. When used in conveyor applications or equipment handling flammable materials, this belt's composition will prevent sparking by discharging accumulated static electricity to grounded pulleys.

[0045] The manufacturing method consists of implementing the following sequence of actions.

[0046] At the first stage, traction layer 4 is produced in the form of a polyester cord, while using automated machines, a cord of the required width and length is woven from polyester threads.

[0047] In the second stage, the middle layer 2 is produced, and during the production process, a cord of polyester fibers (traction layer 4), produced on automated machines, is placed in the mold with thermoplastic, and then pressed.

[0048] At the third stage, the bottom layer 3 is formed, while the prepared synthetic rubber NBR with impurities (carbon black, silicon fillers and graphite particles) is applied to the previously obtained traction 4 and middle layers 2 using the extrusion method and is vulcanized in press molds at a temperature of 180°C.

[0049] At the fourth stage, the top layer 1 made of synthetic fabric is applied, during which the synthetic fabric is glued with epoxy adhesive to the previously manufactured traction 4, middle 2, bottom 3 layers, after which the synthetic fabric is subjected to heat treatment.

[0050] The flat drive belt functions as a flexible element for transmitting torque between pulleys in mechanical systems. Its operation is based on a combination of friction, strength, and elasticity of materials. The belt structure and the materials used allow the use of the upper layer 1 and lower layer 3 to absorb and transmit torque. The load transmitted from the driving pulley is transferred, due to frictional forces, from the upper layer 1 or lower layer 3 to the middle layer 2 and traction layer 4, which absorb the load and transmit torque to the driven pulley through the upper layer 1 or lower layer 3 at the point of contact with the driven pulley. Traction layer 4, due to the use of a unique polyester cord, has high tensile strength (up to 1000 N / mm 2) and minimal elongation under load (no more than 1%), and ensures good flexibility and stable operation at high temperatures and humidity. The use of thermoplastic in the middle layer (layer 2) ensures the required elasticity and resilience, which absorbs shock and vibration during operation. This also reduces the product's weight, increases the operating temperature range, and simplifies the manufacturing process by eliminating additional operations, as well as the cost of the product. Thermoplastic is also resistant to splitting and delamination, and allows for the splicing of the endless belt using a press without gluing. The addition of graphite particles to the materials of the top layer (layer 1) and bottom layer (layer 3) ensures the transfer of static electricity to the grounded pulley, preventing sparking during operation.The use of a synthetic fabric impregnated with an antifriction compound and having a fine-mesh texture in the top layer (layer 1) improves pulley traction and ensures resistance to aging and wear. The bottom layer (layer 3), formed by a layer of NBR synthetic rubber with fillers (carbon black, silica fillers, and graphite particles), ensures wear resistance and the necessary pulley traction, while the presence of microribs allows for heat exchange to prevent belt overheating.

[0051] The unique structure provides effective performance properties in various operating conditions at temperatures from -20° to +70°C, resistance to oils, alkalis and ultraviolet radiation, as well as an increased service life compared to analogues.

[0052] Thus, the proposed flat drive belt and its manufacturing method ensure high efficiency by improving its antistatic and frictional properties.

Claims

1. A flat drive belt comprising an upper layer, a middle layer, a lower layer and a traction layer, characterized in that the upper layer is made of a synthetic fabric having a fine-mesh texture and also containing graphite particles and impregnated with an antifriction composition in a ratio of up to 15% by weight of the composition, while the lower layer contains graphite particles.

2. The belt according to item 1, characterized in that the top layer is made of synthetic fabric containing carbon threads.

3. The belt according to paragraph 1, characterized in that the middle layer is made of thermoplastic in a ratio, wt. %, of up to 55% of the composition.

4. The belt according to item 1, characterized in that the bottom layer is made of NBR synthetic rubber with the addition of carbon black and silicon fillers.

5. The belt according to item 1, characterized in that the bottom layer has microribs.

6. The belt according to item 1, characterized in that the bottom layer is made of NBR synthetic rubber with the addition of graphite particles in a ratio of 10-15% by weight of the composition.

7. The belt according to paragraph 1, characterized in that the traction layer is made in the form of a polyester cord in a ratio, wt. %, of up to 15% of the composition, made of high-strength polyester fibers woven into a dense mesh.

8. A method for manufacturing a flat drive belt according to claim 1, characterized in that it includes four successive manufacturing stages: at the first stage, a traction layer is manufactured in the form of a polyester cord, wherein a cord of the required width and length is woven from polyester threads using automated machines; then, at the second stage, a middle layer is manufactured, wherein during the manufacturing process, a cord of polyester fibers, manufactured on automated machines, is placed in a press mold with thermoplastic, after which they are pressed; then, at the third stage, a bottom layer is formed, wherein prepared synthetic rubber NBR with impurities such as carbon black, silicon fillers and graphite particles is applied to the previously obtained traction and middle layers using an extrusion method, and it is vulcanized in press molds at a temperature of 180 ° C;then, at the fourth stage, a top layer is applied, made of synthetic fabric with a fine-mesh texture, also containing graphite particles and impregnated with an antifriction compound, in a ratio of up to 15% by weight, during which the synthetic fabric is glued with epoxy adhesive to the previously manufactured traction, middle, and bottom layers, after which the synthetic fabric is subjected to heat treatment.

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