Flexible cable for robot

Abstract

The invention relates to the technical field of cables, and provides a flexible cable for a robot, which comprises a cable core and a sheath layer wrapping the cable core, the cable core comprises signal lines and power lines. Each signal line sequentially comprises a conductor, a belting layer and a shielding layer from inside to outside; the shielding layer sequentially comprises a first shielding layer and a second shielding layer from inside to outside; the first shielding layer is a bare copper wire mesh layer; the second shielding layer is a tinned copper wire mesh layer; the belting layer is a glass fiber tape layer; the sheath layer comprises the following raw material components in parts by weight: 80-90 parts of polyvinyl chloride resin, 20-30 parts of a plasticizer, 2-4 parts of an anti-aging agent, 2-4 parts of a calcium-zinc stabilizer, 1-4 parts of a lubricant and 6-16 parts of a flame retardant; the plasticizer is prepared from dioctyl phthalate, polyethylene glycol adipate and p-methoxyacetophenone. According to the technical scheme, the problem of low elongation at break of the flexible cable for the robot in the prior art is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of cables, and specifically, to a flexible cable for robots. Background Art

[0002] In recent years, the global technology field has witnessed continuous explosive growth. The robotics industry has taken the lead and become the core force driving the transformation of various industries. Under the framework of Industry 4.0, industrial robots have fully penetrated traditional manufacturing industries such as automobile manufacturing and electronic processing, undertaking high-precision tasks such as welding and assembly, and helping enterprises achieve a leap in production efficiency and cost control. In the medical industry, from high-precision robotic arms that assist doctors in performing minimally invasive surgeries to logistics robots that undertake material distribution in hospitals, their emergence has greatly improved the quality and efficiency of medical services. In daily life, household cleaning robots, companion robots, etc. have entered thousands of households, greatly improving people's living experience.

[0003] With the continuous expansion of the application landscape of robots, their operating environments and tasks have become increasingly complex and diverse. From high-temperature and high-pressure chemical production workshops to narrow and humid underground pipeline detection scenarios, and then to service environments that require close human-robot collaboration, robots need to respond flexibly. This poses unprecedentedly stringent requirements on the key component of robots - cables. As the "lifeline" for power and signal transmission, cables need to work stably under various complex working conditions.

[0004] During the actual operation of robots, the frequent bending and twisting movements at their joints subject the cables to high-intensity and complex mechanical stresses. Moreover, factors such as temperature, humidity, and chemical corrosion in different environments also constantly test the comprehensive performance of the cables. In traditional cable designs, even when commonly used materials such as cross-linked polyethylene and rubber are selected, which have a certain foundation in terms of insulation and flexibility, the problem of insufficient elongation at break of cables for robots becomes prominent in the face of the high-frequency and large-amplitude movements of today's robots. In particular, the elongation at break of the cable sheath layer is crucial. Frequent cracking of the cable sheath layer exposes the internal wires, leading to short-circuit faults, which seriously affects the stability and reliability of robot operation. In this situation, it is of crucial significance to develop a flexible cable for robots with a highly flexible sheath layer. Summary of the Invention

[0005] The present invention provides a flexible cable for robots, which solves the problem of low elongation at break of the sheath layer of flexible cables for robots in related technologies.

[0006] The technical solution of the present invention is as follows: The present invention provides a flexible cable for robots, comprising a cable core and a sheath layer wrapped around the cable core; The cable core includes signal lines and power lines; the signal lines sequentially include a conductor, a tape layer, and a shielding layer from the inside to the outside; the shielding layer sequentially includes a first shielding layer and a second shielding layer from the inside to the outside; the first shielding layer is a bare copper wire mesh layer; the second shielding layer is a tinned copper wire mesh layer; the tape layer is a glass fiber tape layer; The raw materials of the sheath layer include the following components in parts by weight: 80-90 parts of polyvinyl chloride resin, 20-30 parts of plasticizer, 2-4 parts of antioxidant, 2-4 parts of calcium-zinc stabilizer, 1-4 parts of lubricant, and 6-16 parts of flame retardant; The plasticizer includes dioctyl phthalate, polyethylene glycol adipate, and p-methoxyacetophenone.

[0007] As a further technical solution, the mass ratio of dioctyl phthalate, polyethylene glycol adipate, and p-methoxyacetophenone is 7:3:1-3.

[0008] In the present invention, by adjusting the mass ratio of dioctyl phthalate, polyethylene glycol adipate, and p-methoxyacetophenone to 7:3:1-3, the elongation at break of the sheath layer of the cable for robots is further improved.

[0009] As a further technical solution, the mass ratio of dioctyl phthalate, polyethylene glycol adipate, and p-methoxyacetophenone is 7:3:2.

[0010] In the present invention, by adjusting the mass ratio of dioctyl phthalate, polyethylene glycol adipate, and p-methoxyacetophenone to 7:3:2, the elongation at break of the flexible cable for robots is further improved.

[0011] As a further technical solution, the polyvinyl chloride resin includes polyvinyl chloride resin A and polyvinyl chloride resin B; The model of the polyvinyl chloride resin A is DG-1000K, and the model of the polyvinyl chloride resin B is SG-5.

[0012] As a further technical solution, the mass ratio of the polyvinyl chloride resin A to the polyvinyl chloride resin B is 8:3-5.

[0013] In the present invention, by adjusting the mass ratio of the polyvinyl chloride resin A to the polyvinyl chloride resin B to 8:3-5, the tensile strength of the flexible cable for robots is improved.

[0014] As a further technical solution, the mass ratio of the polyvinyl chloride resin A to the polyvinyl chloride resin B is 2:1.

[0015] In the present invention, by adjusting the mass ratio of the polyvinyl chloride resin A to the polyvinyl chloride resin B to 2:1, the tensile strength of the sheath layer of the flexible cable for robots is improved.

[0016] As a further technical solution, the anti-aging agent includes one or both of anti-aging agent MB and anti-aging agent D; The lubricant includes one or more of stearic acid, polyethylene wax, and oxidized polyethylene wax; The flame retardant includes one or more of antimony trioxide, zinc borate, and aluminum hydroxide.

[0017] In the present invention, an anti-aging agent is added to the raw materials. The anti-aging agent can inhibit the aging of materials caused by high temperature, light, or oxidation environment, and delay yellowing and embrittlement; In the present invention, a lubricant is added to the raw materials. The lubricant reduces the friction between the material and the screw and the mold, reduces energy consumption, and avoids melt fracture; In the present invention, a flame retardant is added to the raw materials. The flame retardant improves the flame retardant grade of the cable and ensures the safety of the robot during operation.

[0018] The present invention also provides a method for preparing a flexible cable for a robot, comprising the following steps: Mix the raw materials of the sheath layer and extrude and wrap them on the surface of the cable core to obtain a flexible cable for a robot.

[0019] As a further technical solution, during the extrusion, the temperature of zone 1 is 120 - 130 °C, the temperature of zone 2 is 140 - 150 °C, and the temperature of zone 3 is 120 - 130 °C.

[0020] The present invention also provides an application of the flexible cable for a robot or the flexible cable for a robot prepared by the preparation method in a robot.

[0021] The working principle and beneficial effects of the present invention are as follows: In the present invention, a calcium-zinc stabilizer is added to inhibit the generation of HCl due to heat decomposition of PVC during processing and long-term use, and prevent material degradation; the plasticizers include dioctyl phthalate, polyethylene glycol adipate, and p-methoxyacetophenone, which improve the elongation at break of the flexible cable for a robot. Therefore, the flexibility of the sheath layer of the flexible cable for a robot is increased, and the stability and reliability during the operation of the robot are ensured. Specific Embodiments

[0022] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0023] In the following examples and comparative examples, the content of dioctyl phthalate is 99.9 wt%, the weight-average molecular weight of polyethylene glycol adipate is 2000, the content of p-methoxyacetophenone is 99.9 wt%, the model of calcium-zinc stabilizer is SAK-CZL56-NP, purchased from Shandong Tunan New Materials Co., Ltd.; the model of polyethylene wax is AC-6A, and the model of oxidized polyethylene wax is OA6; the polyvinyl chloride resin of model SG-5 is purchased from Jinan Xiangfeng Weiye Chemical Co., Ltd.

[0024] Example 1 A flexible cable for robots, comprising a cable core and a sheath layer wrapped around the cable core; the cable core includes a signal line and a power line; the signal line sequentially includes a conductor, a tape layer, and a shielding layer from the inside to the outside; the shielding layer sequentially includes a first shielding layer and a second shielding layer from the inside to the outside; the first shielding layer is a bare copper wire mesh layer; the second shielding layer is a tin-plated copper wire mesh layer; the tape layer is a glass fiber tape layer; the raw materials of the sheath layer include the following components in parts by weight: 90 parts of polyvinyl chloride resin of model DG-1000K, 30 parts of plasticizer, 4 parts of antioxidant MB, 4 parts of calcium-zinc stabilizer, 4 parts of stearic acid, and 16 parts of antimony trioxide; The plasticizer includes dioctyl phthalate, polyethylene glycol adipate, and p-methoxyacetophenone in a mass ratio of 7:3:5; The preparation method of the flexible cable for robots includes the following steps: Mix the raw materials of the sheath layer, and extrude and wrap them on the surface of the cable core to obtain a flexible cable for robots; During extrusion, the temperature of the first zone is 130 °C, the temperature of the second zone is 150 °C, and the temperature of the third zone is 130 °C.

[0025] Example 2 A flexible cable for robots, comprising a cable core and a sheath layer wrapped around the cable core; the cable core includes a signal line and a power line; the signal line sequentially includes a conductor, a tape layer, and a shielding layer from the inside to the outside; the shielding layer sequentially includes a first shielding layer and a second shielding layer from the inside to the outside; the first shielding layer is a bare copper wire mesh layer; the second shielding layer is a tin-plated copper wire mesh layer; the tape layer is a glass fiber tape layer; the raw materials of the sheath layer include the following components in parts by weight: 80 parts of polyvinyl chloride resin of model DG-1000K, 20 parts of plasticizer, 2 parts of antioxidant D, 2 parts of calcium-zinc stabilizer, 1 part of polyethylene wax, and 6 parts of zinc borate; The plasticizer includes dioctyl phthalate, polyethylene glycol adipate, and p-methoxyacetophenone in a mass ratio of 7:3:0.4; The preparation method of the flexible cable for robots includes the following steps: Mix the raw materials of the sheath layer, and extrude and wrap them on the surface of the cable core to obtain a flexible cable for robots; During extrusion, the temperature of the first zone is 120 °C, the temperature of the second zone is 140 °C, and the temperature of the third zone is 120 °C.

[0026] Example 3 A flexible cable for a robot, comprising a cable core and a sheath layer wrapped around the cable core; the cable core includes a signal line and a power line; the signal line sequentially includes a conductor, a tape layer, and a shielding layer from the inside to the outside; the shielding layer sequentially includes a first shielding layer and a second shielding layer from the inside to the outside; the first shielding layer is a bare copper wire mesh layer; the second shielding layer is a tin-plated copper wire mesh layer; the tape layer is a glass fiber tape layer; the raw materials of the sheath layer include the following components in parts by weight: 85 parts of polyvinyl chloride resin of model DG-1000K, 25 parts of plasticizer, 3 parts of antioxidant MB, 3 parts of calcium-zinc stabilizer, 2 parts of oxidized polyethylene wax, and 8 parts of aluminum hydroxide; The plasticizer includes dioctyl phthalate, polyethylene glycol adipate, and p-methoxyacetophenone in a mass ratio of 7:3:4; A method for preparing a flexible cable for a robot, comprising the following steps: Mix the raw materials of the sheath layer and extrude and wrap them on the surface of the cable core to obtain a flexible cable for a robot; During extrusion, the temperature of zone 1 is 125 °C, the temperature of zone 2 is 145 °C, and the temperature of zone 3 is 125 °C.

[0027] Example 4 The difference between this example and Example 3 is only that the plasticizer in this example includes dioctyl phthalate, polyethylene glycol adipate, and p-methoxyacetophenone in a mass ratio of 7:3:0.6.

[0028] Example 5 The difference between this example and Example 3 is only that the plasticizer in this example includes dioctyl phthalate, polyethylene glycol adipate, and p-methoxyacetophenone in a mass ratio of 7:3:1.

[0029] Example 6 The difference between this example and Example 3 is only that the plasticizer in this example includes dioctyl phthalate, polyethylene glycol adipate, and p-methoxyacetophenone in a mass ratio of 7:3:2.

[0030] Example 7 The difference between this example and Example 3 is only that the plasticizer in this example includes dioctyl phthalate, polyethylene glycol adipate, and p-methoxyacetophenone in a mass ratio of 7:3:3.

[0031] Example 8 The difference between this example and Example 6 is only that the model of the polyvinyl chloride resin in this example is SG-5.

[0032] Example 9 The difference between this embodiment and Embodiment 6 is only that the raw materials of the sheath layer in this embodiment include the following components in parts by weight: 85 parts of polyvinyl chloride resin, 25 parts of plasticizer, 3 parts of antioxidant MB, 3 parts of calcium-zinc stabilizer, 2 parts of oxidized polyethylene wax, and 8 parts of aluminum hydroxide; The polyvinyl chloride resin includes polyvinyl chloride resin of model DG-1000K and polyvinyl chloride resin of model SG-5 with a mass ratio of 4:3.

[0033] Embodiment 10 The difference between this embodiment and Embodiment 9 is only that the polyvinyl chloride resin in this embodiment includes polyvinyl chloride resin of model DG-1000K and polyvinyl chloride resin of model SG-5 with a mass ratio of 4:1.

[0034] Embodiment 11 The difference between this embodiment and Embodiment 9 is only that the polyvinyl chloride resin in this embodiment includes polyvinyl chloride resin of model DG-1000K and polyvinyl chloride resin of model SG-5 with a mass ratio of 8:3.

[0035] Embodiment 12 The difference between this embodiment and Embodiment 9 is only that the polyvinyl chloride resin in this embodiment includes polyvinyl chloride resin of model DG-1000K and polyvinyl chloride resin of model SG-5 with a mass ratio of 2:1.

[0036] Embodiment 13 The difference between this embodiment and Embodiment 9 is only that the polyvinyl chloride resin in this embodiment includes polyvinyl chloride resin of model DG-1000K and polyvinyl chloride resin of model SG-5 with a mass ratio of 8:5.

[0037] Comparative Example 1 The difference between this comparative example and Embodiment 3 is only that the plasticizer in this comparative example includes dioctyl phthalate and polyethylene glycol adipate with a mass ratio of 7:3.

[0038] Comparative Example 2 The difference between this comparative example and Embodiment 3 is only that the plasticizer in this comparative example includes dioctyl phthalate and p-methoxyacetophenone with a mass ratio of 7:4.

[0039] Comparative Example 3 The difference between this comparative example and Embodiment 3 is only that the plasticizer in this comparative example includes polyethylene glycol adipate and p-methoxyacetophenone with a mass ratio of 3:4.

[0040] Comparative Example 4 The difference between this comparative example and Embodiment 3 is only that the plasticizer in this comparative example is dioctyl phthalate.

[0041] Comparative Example 5 The difference between this comparative example and Example 3 is only that the plasticizer in this comparative example is polyethylene glycol adipate.

[0042] Comparative Example 6 The difference between this comparative example and Example 3 is only that the plasticizer in this comparative example is p-methoxyacetophenone.

[0043] Comparative Example 7 The difference between this comparative example and Example 3 is only that this comparative example has no plasticizer.

[0044] Experimental Example 1 The elongation at break of the sheath layers of the flexible cables for robots in Examples 1 to 7 and Comparative Examples 1 to 7 was tested according to the method specified in GB / T 1040.1-2018 Plastics - Determination of tensile properties - Part 1: General principles, and the test results are shown in Table 1.

[0045] Table 1 Test results of elongation at break

[0046] As can be seen from Table 1, the elongation at break of the sheath layers of the flexible cables for robots in Examples 1 to 7 reached more than 321%. Therefore, in the present invention, dioctyl phthalate, polyethylene glycol adipate and p-methoxyacetophenone are used as plasticizers, which improves the elongation at break of the sheath layers of the flexible cables for robots.

[0047] Experimental Example 2 The tensile strength of the sheath layers of the flexible cables for robots in Examples 6 and 8 to 13 was tested according to the method specified in GB / T 1040.1-2018 Plastics - Determination of tensile properties - Part 1: General principles, and the test results are shown in Table 2.

[0048] Table 2 Test results of tensile strength

[0049] As can be seen from Table 2, the tensile strength of the sheath layers of the flexible cables for robots in Examples 6 and 8 to 13 reached 15.3 MPa or more, indicating that in the present invention, the use of polyvinyl chloride resins of model DG-1000K and model SG-5 has a synergistic effect and improves the tensile strength of the sheath layers of the flexible cables for robots.

[0050] Experimental Example 3 The sheath layers of the flexible cables for robots in Examples 1 to 3 were tested for oxygen index according to the method specified in GB / T 2406.1-2008 Plastics - Determination of burning behaviour by oxygen index - Part 1: Guidelines; and the Shore hardness A was tested according to the method specified in GB / T 2411-2008 Plastics and ebonite - Determination of indentation hardness by means of a durometer (Shore hardness). The test results are shown in Table 3.

[0051] Table 3 Test Results of Oxygen Index and Shore Hardness

[0052] As can be seen from Table 3, the flexible cables for robots in the present invention can meet the requirements of robot use.

[0053] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A flexible cable for a robot, characterized in that: It comprises a cable core and a sheath layer wrapped around the cable core; The cable core includes a signal line and a power line; the signal line includes a conductor, a tape layer, and a shielding layer from the inside to the outside; the shielding layer includes a first shielding layer and a second shielding layer from the inside to the outside; the first shielding layer is a bare copper wire mesh layer; the second shielding layer is a tinned copper wire mesh layer; the tape layer is a glass fiber tape layer; The raw materials of the sheath layer include the following components in parts by weight: 80-90 parts of polyvinyl chloride resin, 20-30 parts of plasticizer, 2-4 parts of antioxidant, 2-4 parts of calcium zinc stabilizer, 1-4 parts of lubricant, and 6-16 parts of flame retardant; The plasticizers include dioctyl phthalate, polyethylene adipate and p-methoxyacetophenone.

2. A flexible cable for a robot according to claim 1, characterized in that: The mass ratio of dioctyl phthalate, polyethylene adipate and p-methoxyacetophenone is 7:3:1-3.

3. A flexible cable for a robot according to claim 2, characterized in that: The mass ratio of dioctyl phthalate, polyethylene adipate and p-methoxyacetophenone is 7:3:

2.

4. A flexible cable for a robot according to claim 1, characterized in that: The polyvinyl chloride resin includes polyvinyl chloride resin A and polyvinyl chloride resin B; The model of the polyvinyl chloride resin A is DG-1000K, and the model of the polyvinyl chloride resin B is SG-5.

5. A flexible cable for a robot according to claim 4, characterized in that: The mass ratio of the polyvinyl chloride resin A to the polyvinyl chloride resin B is 8:3-5.

6. A flexible cable for a robot according to claim 5, characterized in that: The mass ratio of the polyvinyl chloride resin A to the polyvinyl chloride resin B is 2:

1.

7. A flexible cable for a robot according to claim 1, characterized in that: The antioxidant includes one or two of antioxidant MB and antioxidant D; The lubricant includes one or more of stearic acid, polyethylene wax, and oxidized polyethylene wax; The flame retardant includes one or more of antimony trioxide, zinc borate, and aluminum hydroxide.

8. A method for preparing a flexible cable for a robot, used for preparing a flexible cable for a robot as claimed in any one of claims 1 to 7, characterized in that: The following steps are involved: The raw materials of the sheath layer are blended, extruded and wrapped on the surface of the cable core to obtain a flexible cable for robots.

9. The method for preparing a flexible cable for a robot according to claim 8, characterized in that: During the extrusion, the temperature of the first zone is 120-130°C, the temperature of the second zone is 140-150°C, and the temperature of the third zone is 120-130°C.

10. Use of the flexible cable for robot according to any one of claims 1 to 7 or the flexible cable for robot prepared by the preparation method according to any one of claims 8 to 9 in a robot.

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