TWI695130B - Toothed belt - Google Patents

Abstract

The present invention relates to a toothed belt, which is characterized by having a belt body including: a plurality of core wires, which extend in the belt length direction and are arranged in the belt width direction; the back portion, which is embedded with the plural number A core wire; and a plurality of teeth, which are opposite to the back portion in the belt thickness direction and are arranged separately from each other in the belt length direction; and the back portion and the plurality of teeth are integrated by a thermoplastic elastomer Forming, the belt strength per 1 mm belt width is 1.85 kN or more, the pitch of the plurality of teeth is 20 mm or more, the height of each of the plurality of teeth is 5 mm or more, and the thickness of the back portion is 4 mm the above.

Description

Toothed belt

The invention relates to a toothed belt in which a back surface portion and a plurality of tooth portions are integrally formed of thermoplastic elastomer.

Toothed belts are widely used as power transmission belts for general industrial machinery, agricultural machinery, etc. In recent years, the industry has promoted the application of heavy weight transported objects. In order to realize the application to heavy-weight transported objects, it is more effective to increase the load resistance compared with the increase in the overall size of the toothed belt (especially the height of the teeth). However, in order to save device space, miniaturization is also required, and in particular, the increase in the load resistance under the suppression of the belt width is expected by the industry.

As a technique for increasing the load resistance while suppressing the belt width, a technique of arranging a plurality of core wires in the belt thickness direction (refer to Patent Documents 1 and 2), and a technique of densely arranging core wires in the belt width direction without gaps are known , The technique of increasing the diameter of the core wire, etc. [Prior Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Application Publication No. 2014-142046 [Patent Document 2] Japanese Patent Application Publication No. 2016-211734

[Problems to be solved by the invention]

However, Patent Documents 1 and 2 do not disclose a specific belt strength size and a tooth structure (pitch, height), etc. that are preferably applied to a heavy-weight conveyed object.

An object of the present invention is to provide a toothed belt that can increase the load resistance while suppressing the width of the belt and is preferably applied to a heavy-weight conveyed object. [Technical means to solve the problem]

According to the present invention, a toothed belt can be provided, which is characterized by being provided with a belt body including: a plurality of core wires, each of which extends in the belt length direction and is arranged in the belt width direction; A plurality of core wires; and a plurality of teeth, which are opposite to the back surface in the belt thickness direction, and are arranged separately from each other in the belt length direction; and the back surface and the plurality of teeth are made of thermoplastic elastomer Integrally formed, the belt strength per 1 mm belt width is 1.85 kN or more, the pitch of the plurality of teeth is 20 mm or more, the height of each of the plurality of teeth is 5 mm or more, and the thickness of the back portion is 4 mm or more.

According to the present invention, it is possible to provide a toothed belt that can increase the load resistance while suppressing the belt width as shown in the following embodiment, and is preferably applied to a heavy-weight conveyed object.

In the present invention, each of the plurality of core wires may include wires twisted by steel wires, aromatic polyamide fibers, or carbon fibers. In addition, each of the aforementioned plurality of core wires may also be composed of a steel wire, the strength may be 7-8 kN, and the diameter may be 2.3-2.6 mm. In this case, by using a steel wire with a low elongation and high strength as a core wire, the belt strength per unit width can be better improved.

The pitch of the plurality of core wires may be 3.0-3.7 mm, and the interval between the plurality of core wires may be 0.4-1.4 mm. In this case, as shown in the following embodiment, the belt strength per unit width can be improved better by a suitable combination of the pitch and spacing of the core wires.

The aforementioned thermoplastic elastomer may be selected from the group consisting of polyurethane-based thermoplastic elastomer, polyester-based thermoplastic elastomer, polystyrene-based thermoplastic elastomer, polyolefin-based thermoplastic elastomer, polyamide-based thermoplastic elastomer, and At least one type of vinyl chloride-based thermoplastic elastomer. The aforementioned thermoplastic elastomer may be a polyurethane thermoplastic elastomer, and the hardness may be 85 to 95°. In this case, a toothed belt excellent in mechanical properties and durability can be obtained. In addition, since polyurethane-based thermoplastic elastomers are widely used for transmission belts and conveyor belts, it is easy to manufacture toothed belts. Moreover, as the type of the polyurethane constituting the polyurethane-based thermoplastic elastomer, it may be a polyether-type polyurethane, a polyester-type polyurethane, or a polycarbonate Type polyurethane. [Effect of invention]

According to the present invention, it is possible to provide a toothed belt that can increase the withstand load while suppressing the belt width, and is preferably applied to a heavy-weight conveyed object.

As shown in FIGS. 1 and 2, a toothed belt 10 according to an embodiment of the present invention includes a belt body 10 a including a plurality of core wires 1, a back portion 2 in which the plurality of core wires 1 are embedded, and a plurality of tooth portions 3.

The core wire 1 of this embodiment is composed of a steel wire (twisted steel fiber wire). The plural core wires 1 each extend in the belt length direction and are arranged in the belt width direction.

The plural tooth portions 3 and the back portion 2 face each other in the belt thickness direction, and are arranged apart from each other in the belt length direction. The back portion 2 and the plurality of teeth 3 are integrally formed of a thermoplastic elastomer. The thermoplastic elastomer constituting the back surface portion 2 and the plurality of teeth portions 3 is a polyurethane thermoplastic elastomer in this embodiment, and the hardness is 85 to 95° (according to JIS K6253:2012, measured by a type A hardness tester ). The type of polyurethane constituting the polyurethane-based thermoplastic elastomer is a polyether-based polyurethane, a polyester-based polyurethane, or a polycarbonate-based polyamine Carbamate.

The toothed belt 10 preferably satisfies the following requirements. • Belt width W=50～150 mm • Overall belt thickness H=9～13 mm • Thickness of back part 2 h2=4～6 mm • Height of each tooth part 3 h3=5～8 mm • Section of tooth part 3 Distance P=20～30 mm • Diameter D of each core wire 1=2.3～2.6 mm • Strength of each core wire 1=7～8 kN • Pitch of core wire 1=3.0～3.7 mm • Interval of core wires 1=0.4 ～1.4 mm (the total value of each interval d is 13～36% of the belt width W) • The belt strength per 1 mm belt width is 1.85 kN or more and 2.60 kN or less.

The toothed belt 10 is used, for example, in the lifting conveyor 50 shown in FIG. 3.

The lifting conveyor 50 has toothed pulleys 51 and 53 arranged side by side and toothed pulleys 52 and 54 arranged side by side. The open toothed belt 10 is cut to a specific width and length, and the two ends of the belt length direction are fixed with jigs and the like to form an endless belt, which are wound around a pair of toothed pulleys arranged up and down. 51, 52 and a pair of toothed pulleys 53, 54. A fixture 58 for fixing the stage 57 is installed on each toothed belt 10. Among the four toothed pulleys 51 to 54, one toothed pulley 52 is driven, and the remaining toothed pulleys 51, 53, 54 pass through The toothed belt 10 is driven synchronously. When the transported object 59 is placed on the stage 57 and the toothed pulley 52 is rotated in the forward direction or the reverse direction, the pair of toothed belts 10 move, and the transported object 59 moves up and down.

The toothed belt 10 is preferably applied to a heavy-weight conveyed object. For example, it can be used in a usage environment where the weight of the conveyed object 59 is 5 to 11 t and a maximum tension of 0.20 to 0.25 kN/mm is applied. In addition, the toothed belt of the present invention may be either open or endless. In addition, the toothed belt of the present invention is not limited to being used for lifting and conveying devices, and can be used for any device. Furthermore, the toothed belt of the present invention may be provided with a reinforcing cloth on the outer peripheral surface and/or the inner peripheral surface of the belt body.

Next, an example of a method of manufacturing the toothed belt 10 will be described.

The toothed belt 10 is manufactured by, for example, the manufacturing apparatus 60 shown in FIG. 4. The manufacturing device 60 includes: a forming drum 61; pulleys 62 and 63 arranged close to the forming drum 61; a pulley 64 arranged horizontally opposite to the forming drum 61; and wound around the pulleys 62 to 64 The endless metal belt is a pressing belt 65; an extrusion head 66 for extruding thermoplastic elastomer; and a core wire supply device (illustration omitted).

A groove for forming the tooth portion 3 is formed on the outer peripheral surface of the forming drum 61 at specific intervals in the circumferential direction. The pulley 64 is movable in the horizontal direction relative to the forming drum 61, and gives a specific tension to the pressing belt 65. The pressing belt 65 is arranged so as to be wound around half of the outer peripheral surface of the forming drum 61, and is pressed against the outer peripheral surface of the forming drum 61 by the tension given from the pulley 64.

The extrusion head 66 supplies the thermoplastic elastomer melted by heating to the outer peripheral surface of the forming drum 61. The core wire supply device (not shown) supplies a plurality of core wires 1 arranged in the axial direction of the forming drum 61 to the outer peripheral surface of the forming drum 61.

The molten thermoplastic elastomer and the plurality of core wires 1 supplied to the outer peripheral surface of the forming drum 61 are drawn between the forming drum 61 and the pressing belt 65 as the forming drum 61 rotates. At this time, by the pressing force of the pressing belt 65, the thermoplastic elastomer is filled in the groove formed on the outer peripheral surface of the forming drum 61, and the tooth portion 3 is formed in the groove. At this time, between the outer peripheral surface of the forming drum 61 and the pressing belt 65, a back surface portion 2 in which a plurality of core wires 1 are embedded is formed. In addition, the thermoplastic elastomer is strongly pressed toward the outer peripheral surface of the forming drum 61 by the pressing force of the pressing belt 65, and the thermoplastic elastomer is cooled and solidified. At a portion where the pressing belt 65 is separated from the forming drum 61, the belt body 10a is continuously taken out.

As described above, according to the present embodiment, it is possible to provide a tooth profile that can suppress the belt width W and increase the load resistance as described below in the embodiment, and is preferably applied to a heavy-weight conveyed object Belt 10.

In the present embodiment, each core wire 1 is formed of steel wire, has a strength of 7 to 8 kN, and a diameter D of 2.3 to 2.6 mm. In this case, by using a steel wire with a feature of low elongation and high strength as the core wire 1, the belt strength per unit width can be reliably improved.

In this embodiment, the pitch Pt of the core wires 1 is 3.0 to 3.7 mm, and the interval d between the core wires 1 is 0.4 to 1.4 mm. In this case, as shown in the embodiments described later, with a better combination of the pitch and interval of the core wires 1, the belt strength per unit width can be more reliably improved. [Example]

The inventors used the above-mentioned manufacturing method to use the tooth profile of AT20 (the tooth profile with a pitch of 20 mm according to ISO17396:2014), and polyurethane (polyester-based polyurethane) The toothed belts of Examples 1 to 9 and Comparative Examples 1 to 3 were produced from thermoplastic elastomers, and tensile tests and running tests were performed on these toothed belts.

The following Tables 1 to 4 show the configurations of the toothed belts of Examples 1 to 9 and Comparative Examples 1 to 3. In addition, the belt widths W of the toothed belts of Examples 1 to 9 and Comparative Examples 1 to 3 were all 135 mm.

Here, in Table 1, in order to compare the case where the pitch P of the tooth portion 3 and the belt strength per 1 mm belt width are variables, the toothed belts of Examples 1 to 3 and Comparative Examples 1 to 3 are described constitute. In addition, in Table 2, in order to compare the case where the pitch Pt of the core wire 1 relative to the toothed belt of Example 1 is a variable, the configurations of the toothed belts of Examples 1, 4, and 5 are described. In addition, in Table 3, the structure of the toothed belts of Examples 1, 6 to 8 is described in order to compare the case where the hardness is changed relative to the toothed belt of Example 1. In addition, in Table 4, the configuration of the toothed belts of Examples 1 and 9 is described in order to compare the case of changing the type of polyurethane with respect to the toothed belt of Example 1.

[Table 1] Table 1 (Comparison of pitch P and belt strength as variables)

[Table 2] Table 2 (Comparison of the pitch Pt of the core wire as a variable)

[Table 3] Table 3 (Comparison of hardness as a variable)

[Table 4] Table 4 (Comparison of changing types of polyurethane)

In the running test, from the toothed belts of Examples 1 to 9 and Comparative Examples 1 to 3, test pieces 10x with a width of 20 mm and a length of 3700 mm were collected, and as shown in FIG. 5, the joints 20 were joined to each Both ends of the test piece 10x forming an endless belt are wound around the driving pulley 71 and the driven pulley 72 of the lifting test machine 70 (the number of teeth of each pulley 71, 72 = 32). Then, a tensile force of 0.25 kN/mm was applied to each test piece 10x, and 1 million cycles (one cycle of forward and reverse indicated by arrows in FIG. 5 as one cycle) were repeatedly moved.

Then, the strength of the test piece 10x before and after the transition test (before and after the transition) of each test piece 10x was measured by a tensile test, and further, the reduction rate of the strength of the test piece 10x before and after the transition test was calculated. The results are described in the items of the strength of the belt before the movement and the strength of the belt after the movement, and the items of the reduction rate of the strength in Tables 1 to 4.

In the tensile test, the width of 20 mm and the length of 500 were collected from the test piece 10x before the movement and the test piece 10x after the movement collected from the toothed belts of Examples 1 to 9 and Comparative Examples 1 to 3, respectively. For a tensile test piece of mm, a tensile test (a tensile speed of 50 mm/min) was performed on each tensile test piece using an Amsler tensile tester, and the strength until breaking was measured.

In addition, observe each test piece 10x after the transition test, and if there is an unfavorable condition such as "tooth defect" or "tooth abrasion", describe its status in the items in the "state after transition" in Tables 1 to 4. When there is no special change, it is recorded as "no defect".

In addition, it is determined whether or not each test piece 10x before and after the transition test is positioned poorly with respect to the drive pulley 71 and the driven pulley 72. Specifically, as shown in FIG. 5, after the transition test, the position of the jig connected to the joint 20 is read out. The jig is linked to the movement of the belt (the joint 20 is joined to the two ends of each test piece 10x to form an endless belt) (the up and down of the joint 20) and moves up and down along the scale rod. The scale reading position of the jig measures the movement The distance before and after the start of the test. Moreover, if the offset distance is less than 3 mm, there is no position offset, if it is more than 3 mm, it is regarded as a position offset, and the situation where there is a position offset is judged as "with". Poor positioning (Table 1 to Table 4 "Poor positioning" item).

From the results of the above migration test, it can be seen that the toothed belts of Examples 1 to 9 and Comparative Examples 1 to 3 were graded A to D according to the criteria shown in Table 5 below and described in Tables 1 to 4. "Decision" item. [Table 5] Table 5

The pitch P of the teeth is more than 20 mm (the pitch P of the teeth is relatively large, and the size of the teeth with the pitch P of the teeth (the length of the teeth in the belt length direction and the tooth height h3 of the teeth ) Is large), and the high-strength (1.85 kN/mm or more) of the toothed belts of Examples 1 to 3 are all A grade.

Comparative Example 1 is a toothed belt with a high-strength, but a tooth pitch P of 14 mm (the tooth size is smaller). When the size of the tooth part with the pitch P of the tooth part is small, compared with the tooth part with a large size, the tooth part tends to be large due to lack of resistance to effective tension (load) applied to one tooth Deformation, as a result, early tooth loss leads to a shortened life and is not practical (D grade).

Comparative Example 2 Although the pitch P of the tooth portion is 20 mm (the size of the tooth portion is large), since the core wire having a smaller diameter and a lower strength than that of Example 1 is used, the tooth shape of the belt strength does not reach 1.85 kN/mm Belt. In this case, when a large load is applied to the toothed belt, since the core wire has a small diameter, extremely high tension is applied to each core wire. As a result, the toothed belt stretches to form poor positioning, which is not practical ( D grade).

Comparative Example 3 is a toothed belt with a pitch P of 14 mm (the size of the teeth is smaller) and a belt strength of less than 1.85 kN/mm. In this case, tooth defects are generated early, and poor positioning is also not practical (D grade).

Examples 4 and 5 are the same as Example 1 except that the pitch Pt of the core wire is changed (enlarged) and the number of core wires embedded in the toothed belt is reduced. The size is large) toothed belt. Due to the reduction in the number of core wires, the belt strength is reduced compared to Example 1, but it has been confirmed that the belt strength of 1.85 kN/mm or more can be maintained after the transition, and there is no "tooth defect" and "tooth wear". The poor condition and poor positioning are practical (B grade).

Examples 6 to 8 except that the hardness of the material constituting the toothed belt (polyurethane-based thermoplastic elastomer) was changed, the pitch P of the tooth portion with the same configuration as in Example 1 was 20 mm (tooth portion The size is large) toothed belt. Example 8 (95°) with high hardness is grade A, but because of the deformation of the tooth portion in the toothed belt with low hardness, it is easy to increase the wear of the tooth portion, so it is grade B in example 7 (85°) , In Example 6 (80°), it is grade C.

Example 9 is the same as Example 1 except that the type of polyurethane (polyurethane-based thermoplastic elastomer) constituting the toothed belt is changed, and the pitch P of the tooth portion having the same configuration as in Example 1 The toothed belt is 20 mm (the size of the teeth is large). In this case, it is A rank equivalent to Example 1.

The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above-mentioned embodiments, as long as it is within the scope of the patent application described, various design changes can be made.

The toothed belt of the present invention can be either open or endless. In addition, the toothed belt of the present invention is not limited to being used for a lifting and conveying device, but can be used for any device. The thermoplastic elastomer is not limited to the polyurethane-based thermoplastic elastomer, and for example, may be a polyester-based thermoplastic elastomer, a polystyrene-based thermoplastic elastomer, a polyolefin-based thermoplastic elastomer, or a polyamide-based thermoplastic elastomer Elastomers, vinyl chloride-based thermoplastic elastomers, etc., may be a combination of two or more of these. The hardness of the thermoplastic elastomer is not limited to 85 to 95°, and may be outside these ranges. The core wire is not limited to being composed of steel wire, but may be composed of, for example, a yarn formed by twisting aromatic polyamide fiber or carbon fiber. A reinforcing cloth can also be provided on the outer peripheral surface and/or inner peripheral surface of the belt body.

This application was created based on Japanese Patent Application No. 2017-085025 filed on April 24, 2017 and Japanese Patent Application No. 2018-079008 filed on April 17, 2018, and the contents are incorporated by reference In this application.

1‧‧‧Core wire 2‧‧‧Back part 3‧‧‧Tooth part 10‧‧‧Toothed belt 10a‧‧‧Belt body 10x‧‧‧Test piece 20‧‧‧Joint 50‧‧‧Elevating conveying device 51‧ ‧‧Toothed belt pulley 52‧‧‧Toothed belt pulley 53‧‧‧Toothed belt pulley 54‧‧‧‧Toothed belt pulley 57‧‧‧Loading table 58‧‧‧Fixture 59‧‧‧Transportation 60‧‧‧Manufacture Device 61‧‧‧Shaping drum 62‧‧‧Pulley 63‧‧‧Pulley 64‧‧‧‧Pulley 65‧‧‧Compression belt 66‧‧‧Extrusion head 70‧‧‧Elevator testing machine 71‧‧‧Drive pulley/ Pulley 72‧‧‧Driven pulley/pulley d‧‧‧Interval of core wire/Interval D‧‧‧Diameter of core wire/diameter H‧‧‧Overall thickness h2‧‧‧ Thickness of back part/Thickness of back part h3‧‧‧ Tooth height / tooth height P‧‧‧ tooth pitch/tooth pitch Pt‧‧‧ core wire pitch W‧‧‧ belt width II‧‧‧ line II-II‧‧‧ line

FIG. 1 is a cross-sectional view of the toothed belt according to an embodiment of the present invention taken along the belt width direction (along line I-I of FIG. 2). FIG. 2 is a cross-sectional view of the toothed belt according to an embodiment of the present invention along the length of the belt (along line II-II of FIG. 1). FIG. 3 is a schematic diagram showing an example in which a toothed belt according to an embodiment of the present invention is used in a lifting and conveying device. FIG. 4 is a schematic diagram for explaining a manufacturing method of a toothed belt according to an embodiment of the present invention. Fig. 5 is a schematic diagram showing a traveling test machine used in the traveling test.

1‧‧‧core wire

2‧‧‧Back

3‧‧‧tooth

10‧‧‧tooth belt

10a‧‧‧Belt body

d‧‧‧Interval/interval of core wire

D‧‧‧Diameter/diameter of core wire

H‧‧‧ Overall thickness

h2‧‧‧ Thickness of back/thickness of back

h3‧‧‧ Height of tooth/tooth height

Pt‧‧‧Pitch of core wire

W‧‧‧Belt width

II-II‧‧‧ line

Claims (10)

A toothed belt is characterized by comprising a belt body comprising: a plurality of core wires, each of which extends in the belt length direction and is arranged in the belt width direction; the back portion, which is embedded with the plurality of core wires; and A plurality of tooth portions, which are opposite to the back surface portion in the belt thickness direction, and are arranged separately from each other in the belt length direction; and the back surface portion and the plurality of tooth portions are integrally formed of a thermoplastic elastomer, every 1 mm The belt strength of the belt width is 1.85 kN or more, the pitch of the plurality of teeth is 20 mm or more, the height of each of the plurality of teeth is 5 mm or more, and the thickness of the back portion is 4 mm or more. The toothed belt according to claim 1, wherein each of the plurality of core wires includes a wire formed by twisting at least any one of steel wire, aromatic polyamide fiber, or carbon fiber. As in the toothed belt of claim 1, each of the aforementioned plural core wires is made of steel wire, with a strength of 7 to 8 kN and a diameter of 2.3 to 2.6 mm. As in the toothed belt of claim 1, the pitch of the plurality of core wires is 3.0 to 3.7 mm, and the interval of the plurality of core wires is 0.4 to 1.4 mm. For example, in the toothed belt of claim 2, the pitch of the plurality of core wires is 3.0 to 3.7 mm, and the interval of the plurality of core wires is 0.4 to 1.4 mm. As in the toothed belt of claim 3, the pitch of the plurality of core wires is 3.0 to 3.7 mm, and the interval of the plurality of core wires is 0.4 to 1.4 mm. The belt according to any one of claims 1 to 6, wherein the thermoplastic elastomer is selected from the group consisting of polyurethane-based thermoplastic elastomer, polyester-based thermoplastic elastomer, polystyrene-based thermoplastic elastomer, polyolefin-based At least one of a group consisting of a thermoplastic elastomer, a polyamide-based thermoplastic elastomer, and a vinyl chloride-based thermoplastic elastomer. The toothed belt according to any one of claims 1 to 6, wherein the aforementioned thermoplastic elastic system polyurethane-based thermoplastic elastomer has a hardness of 85 to 95°. The toothed belt according to claim 7, wherein the aforementioned thermoplastic elastic system polyurethane thermoplastic elastomer has a hardness of 85 to 95°. The toothed belt according to any one of claims 1 to 6, wherein the aforementioned toothed belt is an open type.

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