A rubber-sheathed flexible cable for a frequency converter in a coal mining machine

Abstract

This utility model relates to a rubber-sheathed flexible cable for a frequency converter in a coal mining machine, comprising an inner core and a rubber sheath covering the inner core. The inner core includes: a central support comprising three sets of support arms arranged radially from the center; control wire grooves are provided at the ends of the support arms; power wire grooves are provided between adjacent support arms; three sets of power wires are disposed within the power wire grooves; three sets of control wires are disposed within the control wire grooves, each being sequentially covered from the inside out with a control wire conductor, a control wire insulation layer, a braided shielding layer, and a semi-conductive shielding layer; and three control wire supports, one side of which abuts against the inner side of the rubber sheath, and the other side having an arc-shaped groove corresponding to the control wire groove to clamp the control wires. This provides a rubber-sheathed flexible cable for a frequency converter in a coal mining machine that can clamp and compress the semi-conductive shielding layer and the braided shielding layer of the control wires.

Description

Technical Field

[0001] This utility model relates to the field of mining cable technology, specifically a rubber-sheathed flexible cable for a frequency converter of a coal mining machine. Background Technology

[0002] Currently, the cables used in frequency converters for coal mining machines typically employ a configuration of three sets of power lines and three sets of control lines. The braided metal shielding layer of the control lines often serves as the ground core, providing grounding. However, the braided shielding layer inevitably contains metal wire ends. When the braided shielding layer acts as the ground core, gaps between it and adjacent semi-conductive shielding layers can cause these metal wire ends to discharge at their tips, generating a disordered electric field. This can affect the signal transmission of the control lines. Therefore, when using the braided shielding layer as the ground core, adjacent semi-conductive shielding layers must be tightly compressed with the braided shielding layer to minimize gaps and ensure a as uniform as possible electric field distribution on the control lines. Utility Model Content

[0003] The technical problem to be solved by this utility model is to provide a rubber-sheathed flexible cable for a frequency converter of a coal mining machine that can clamp and compress the semi-conductive shielding layer and the braided shielding layer of the control line.

[0004] To solve the above problems, the technical solution adopted by this utility model is as follows:

[0005] A rubber-sheathed flexible cable for a frequency converter in a coal mining machine includes an inner core and a rubber sheath covering the inner core. The key technology lies in that the inner core comprises:

[0006] The central support includes three sets of support arms arranged radially from the center. The ends of the support arms are provided with control cable grooves, and power cable grooves are provided between two adjacent support arms.

[0007] Three sets of power lines are installed in the power line trough;

[0008] Three sets of control lines are arranged in the control line groove, and from the inside out, they are sequentially covered with a control line conductor, a control line insulation layer, a braided shielding layer and a semi-conductive shielding layer.

[0009] Three sets of control line brackets, one side of which abuts against the inner side of the rubber sheath layer, and the other side of which has an arc-shaped groove, the arc-shaped groove corresponding to the control line groove to clamp the control line.

[0010] In one embodiment of this utility model, the inner core further includes three sets of inner lining fillers. The three sets of inner lining fillers are evenly distributed along the circumferential direction. The outer side of the inner lining filler abuts against the rubber sheath layer. The inner side of the inner lining filler is provided with a fitting groove corresponding to the control line bracket. The control line bracket is fitted in the fitting groove and abuts against the rubber sheath layer through the inner lining filler.

[0011] In one embodiment of this utility model, power line support strips are provided at both ends of the inner lining filling, and the power line support strips of two adjacent inner lining fillings correspond to the power line so as to press the power line against the central support.

[0012] In one embodiment of this utility model, a gap filler is provided between the power line support strips of two adjacent inner linings.

[0013] As one embodiment of this utility model, the control line bracket includes a slotted portion with a cross-section in the shape of "<" and a protrusion disposed at the tip of the slotted portion. The slotted portion is provided with the arc-shaped groove. The slotted portion abuts against the bracket arm. The protrusion is fitted into the inner lining filling and abuts against the rubber sleeve layer through the inner lining filling.

[0014] In one embodiment of this utility model, the cross-section of the protrusion is a single circular shape or two symmetrical circular shapes.

[0015] In one embodiment of this utility model, the rubber sleeve layer includes an inner metal shield and an outer sheath covering the metal shield, wherein the metal shield abuts against the inner lining filling.

[0016] In one embodiment of this utility model, the cross-sections of the control cable groove and the power cable groove are both of superior arc shape, and the cross-section of the arc-shaped groove is of inferior arc shape adapted to the control cable groove.

[0017] The beneficial effects of adopting the above technical solution are as follows:

[0018] The inner core of the cable provided by this utility model includes a central support and a control line support. The control line is clamped by the control line groove on the central support and the arc groove of the control line support. While restricting the relative position of the control line in the cable, the semi-conductive shielding layer of the control line is tightly compressed with the braided shielding layer, reducing the generation of gaps, thereby achieving the purpose of balancing the electric field distribution on the control line. Attached Figure Description

[0019] Figure 1 This is a cross-sectional structural diagram of an embodiment of the present invention.

[0020] Figure 2This is a structural schematic diagram of an embodiment of the present utility model.

[0021] Figure 3 yes Figure 2 A schematic diagram of the structure at point A in the middle.

[0022] Figure 4 This is a schematic diagram of another control line bracket in this embodiment.

[0023] The components are: 1. Power line conductor; 2. Power line insulation layer; 3. Insulation shield; 4. Control line conductor; 5. Control line insulation layer; 6. Braided shield; 7. Semi-conductive shield; 8. Central support; 8-1 Support arm; 8-2 Control line groove; 8-3 Power line groove; 8-4 Weight reduction hole; 9. Control line support; 9-1 Protrusion; 9-2 Slotted part; 9-3 Arc groove; 10 Inner lining filler; 11. Power line support strip; 12. Gap filler; 13. Overall metal shield; 14. Outer sheath. Detailed Implementation

[0024] To make the objectives, technical solutions and advantages of this utility model clearer, the utility model will be clearly and completely described below in conjunction with specific embodiments.

[0025] like Figure 1 The illustrated rubber-sheathed flexible cable for a frequency converter in a coal mining machine includes an inner core and a rubber sheath covering the inner core. In this embodiment, the inner core includes a centrally located central support 8, three sets of power lines and three sets of control lines embedded in the central support 8, and three sets of control line supports 9 for tightening and fixing the control lines. The control lines are sequentially covered from the inside out with a control line conductor 4, a control line insulation layer 5, a braided shielding layer 6, and a semi-conductive shielding layer 7. The metallic braided shielding layer 6 acts as a ground wire and provides shielding. The semi-conductive shielding layer 7 covers the braided shielding layer 6 to reduce discharge phenomena at the wire ends of the braided shielding layer 6.

[0026] See Figures 1 to 3 The central support 8 includes three sets of support arms 8-1 arranged radially from the center. Each support arm 8-1 has a control cable groove 8-2 at its end, and a power cable groove 8-3 is provided between adjacent support arms 8-1. Three sets of power cables are disposed within the power cable grooves 8-3, and three sets of control cables are disposed within the control cable grooves 8-2. One side of the control cable support 9 is tightly pressed against the inner side of the rubber sheath layer, and the other side has an arc-shaped groove 9-3 corresponding to the control cable groove 8-2 to clamp the control cables. The cross-sections of the control cable groove 8-2 and the power cable groove 8-3 are both of a superior arc shape, while the cross-section of the arc-shaped groove 9-3 is of a inferior arc shape adapted to the control cable groove 8-2.

[0027] See Figure 1 and Figure 2 The inner core also includes three sets of inner lining fillers 10, which are evenly distributed along the circumference. The outer side of each inner lining filler 10 abuts against the rubber sheath layer, and the inner side of each inner lining filler 10 is provided with a fitting groove corresponding to the control line bracket 9. The control line bracket 9 is fitted into the fitting groove and abuts against the rubber sheath layer through the inner lining filler 10. Power line support strips 11 are provided at both ends of each inner lining filler 10. The power line support strips 11 of adjacent inner lining fillers 10 correspond to the power lines, and the power line support strips 11 are also pressed against the inner side of the rubber sheath layer to press the power lines firmly against the central bracket 8. Preferably, in this embodiment, the central bracket 8, control line bracket 9, and power line support strips 11 are all made of ethylene propylene rubber. Reinforcing agents such as carbon black and silica are added according to the required support strength. The inner lining filler 10 can be made of natural rubber.

[0028] A gap filler 12 is provided between the power line support strips 11 of two adjacent inner lining fillers 10. The gap filler 12 is made of polypropylene (PP) rope, asbestos rope or fiberglass rope.

[0029] See Figure 1 and Figure 3 The control line bracket 9 includes a slotted portion 9-2 with a "<" shaped cross-section and a protrusion 9-1 located at the tip of the slotted portion 9-2. An arc-shaped groove 9-3 is formed on the slotted portion 9-2, which abuts against the bracket arm 8-1. The protrusion 9-1 is fitted into the inner lining filling 10 and abuts against the rubber sheath layer through the inner lining filling 10. See also... Figure 1 and Figure 3 The cross-section of the protrusion 9-1 is a single circle, preferably using... Figure 4 The structure, with a cross-section comprising two symmetrical circular shapes, provides better contact between the control line bracket and the rubber sheath layer, reducing the risk of misalignment, but increases the overall mass of the cable. The junction of the protrusion 9-1 and the slotted portion 9-2 is angled, allowing the protrusion 9-1 to be fitted into the fitting groove of the inner lining filler 10.

[0030] See Figure 1 and Figure 2 The rubber sheath layer includes an inner metal shield 13 and an outer sheath 14 covering the metal shield 13, wherein the metal shield abuts against the inner lining filling 10.

[0031] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A rubber-sheathed flexible cable for a frequency converter in a coal mining machine, comprising an inner core and a rubber sheath covering the inner core, characterized in that, The inner core includes: The central support (8) includes three sets of support arms (8-1) arranged radially from the center. The ends of the support arms (8-1) are provided with control grooves (8-2), and power grooves (8-3) are provided between two adjacent support arms (8-1). Three sets of power lines are installed in the power line trough (8-3); Three sets of control lines are set in the control line groove (8-2), and from the inside to the outside, they are covered with control line core conductor (4), control line core insulation layer (5), braided shielding layer (6) and semi-conductive shielding layer (7). Three sets of control line brackets (9) have one side abutting against the inner side of the rubber sheath layer, and the other side is provided with an arc-shaped groove (9-3). The arc-shaped groove (9-3) corresponds to the control line groove (8-2) to clamp the control line.

2. The rubber-sheathed flexible cable for a frequency converter in a coal mining machine according to claim 1, characterized in that, The inner core also includes three sets of inner lining fillers (10). The three sets of inner lining fillers (10) are evenly distributed along the circumferential direction. The outer side of the inner lining filler (10) abuts against the rubber sheath layer. The inner side of the inner lining filler (10) is provided with a fitting groove corresponding to the control line bracket (9). The control line bracket (9) is fitted in the fitting groove and abuts against the rubber sheath layer through the inner lining filler (10).

3. The rubber-sheathed flexible cable for a frequency converter in a coal mining machine according to claim 2, characterized in that, Both ends of the inner lining filling (10) are provided with power line support strips (11), and the power line support strips (11) of two adjacent inner lining fillings (10) correspond to the power line so as to press the power line against the central support (8).

4. The rubber-sheathed flexible cable for a frequency converter in a coal mining machine according to claim 3, characterized in that, A gap filler (12) is provided between the power line support strips (11) of two adjacent inner lining fillers (10).

5. The rubber-sheathed flexible cable for a frequency converter in a coal mining machine according to claim 2, characterized in that, The control line bracket (9) includes a slotted portion (9-2) with a cross-section in the shape of "<" and a protrusion (9-1) provided at the tip of the slotted portion (9-2). The slotted portion (9-2) is provided with an arc-shaped groove (9-3). The slotted portion (9-2) abuts against the bracket arm portion (8-1). The protrusion (9-1) is fitted into the inner lining filling (10) and abuts against the rubber sleeve layer through the inner lining filling (10).

6. The rubber-sheathed flexible cable for a frequency converter in a coal mining machine according to claim 5, characterized in that, The cross-section of the protrusion (9-1) is a single circle or two symmetrical circles.

7. The rubber-sheathed flexible cable for a frequency converter in a coal mining machine according to claim 2, characterized in that, The rubber sheath layer includes an inner metal shield (13) and an outer sheath (14) covering the metal shield (13), the metal shield being against the inner lining filler (10).

8. The rubber-sheathed flexible cable for a frequency converter in a coal mining machine according to claim 1, characterized in that, The cross-sections of the control groove (8-2) and the power groove (8-3) are both of superior arc shape, while the cross-section of the arc groove (9-3) is of inferior arc shape that is adapted to the control groove (8-2).

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