ENERGY SUPPLY UNIT AND SWIVEL JOINT

Abstract

An energy supply unit 50 mounted on a swivel joint is provided, wherein the energy supply unit contains: a rotary transformer 53, which is connected to an upper oscillating body ora lower chassis body of a work vehicle; a vibration circuit 52, which is coupled to the upper vibration body, converts electrical energy into an alternating current and supplies the alternating current to the rotary transformer; and a smoothing circuit 54, which is coupled to the lower chassis body and converts the electrical energy output by the rotary transformer 53 into a direct current, wherein an electrode on a negative side of the smoothing circuit 54 is electrically coupled to a housing of the lower chassis body and an electrode on a positive side of the smoothing circuit 54 is led out of a lower section of the swivel joint via a cable which is inserted through a tube 21 provided inside the swivel joint along an axial direction.

Description

Area

[0001] The present invention relates to an energy supply unit and a pivot joint. background

[0002] For example, in a swing joint of a work vehicle including an upper swing body, such as an excavator, and a lower traveling body, a plurality of hydraulic pipes are rotatably arranged to control an engine, a bucket, and the like. Thus, the swing joint is provided with a plurality of hydraulic oil flow paths through which high-pressure and high-speed hydraulic oil can flow. A known technique is to use a rotary transformer to transmit electrical power from the upper side of the swing body to the lower side of the traveling body of the work vehicle. Citation listPatent literature

[0003] Patent Literature 1: JP S63-266292 A Abstract Technical problem

[0004] When transmitting electrical power using a rotary transformer, at least two cables are required within the swivel joint because the electrical power being transmitted is alternating current. In the technique described in Patent Literature 1, a cable is installed inside the swivel joint to transmit the output of the rotary transformer while maintaining the alternating current. Therefore, a two-core cable is laid inside the swivel joint.

[0005] However, if a new cable hole is introduced into the swivel joint, the wall thickness of the swivel joint will decrease. As a result, the strength of the swivel joint may decrease. Furthermore, if a piping is provided in the hydraulic oil flow path of the swivel joint, the area of ​​the hydraulic oil flow path through the piping may be reduced, resulting in increased pressure loss.

[0006] One aspect of the present invention is to suppress a decrease in the strength of a swing joint and to suppress a decrease in the area of ​​a hydraulic oil flow path of the swing joint. Solution to the problem

[0007] According to one aspect of the present invention, a power supply unit is mounted on a pivot joint of a work vehicle, the power supply unit comprising: a rotary transformer coupled to an upper vibrating body and a lower traveling body of the work vehicle, respectively; an oscillation circuit coupled to the upper vibrating body, converting electrical power into an alternating current, and supplying the alternating current to the rotary transformer;and a smoothing circuit coupled to the lower traveling body and converting the electrical power output from the rotary transformer into a direct current, wherein an electrode on a negative side of the smoothing circuit is electrically coupled to a housing of the lower traveling body, and an electrode on the positive side of the smoothing circuit is led out of the lower portion of the pivot joint via a cable guided in the axial direction through a pipe provided inside the pivot joint.

[0008] According to another aspect of the present invention, a pivot joint comprises: the power supply unit; a rotor; a shaft disposed in a bore of the rotor; and a hydraulic oil flow path provided within the shaft along an axial direction. Advantageous effects of the invention

[0009] According to the aspect of the present invention, it is possible to suppress a decrease in the strength of a pivot joint and a decrease in the area of ​​a hydraulic oil flow path of the pivot joint. Brief Description of the Drawings Fig. 1 is a view schematically illustrating a work vehicle according to an embodiment. Fig. 2 is a side cross-sectional view illustrating a pivot joint according to this embodiment. Fig. 3 is a side cross-sectional view illustrating a power supply unit according to this embodiment. Fig. 4 is a perspective view illustrating the power supply unit according to this embodiment. Fig. 5 is a schematic view illustrating the power supply unit according to this embodiment. Description of the embodiments

[0010] An embodiment of the present invention will be described below with reference to the drawings, but the present invention is not limited to this embodiment. The components of the embodiment described below can be combined as appropriate. Furthermore, some components may not be used. [Embodiment] <arbeitsfahrzeug>

[0011] Fig. 1 is a view schematically illustrating a work vehicle according to an embodiment. A work vehicle MV includes a lower traveling body 100, an upper swing body 200, a rotating mechanism 300, and a swing joint 1. The upper swing body 200 is pivotally supported by the lower traveling body 100. The work vehicle MV is, for example, a work vehicle including the upper swing body 200, e.g., an excavator, and the lower traveling body 100.

[0012] The lower traveling body 100 and the upper oscillating body 200 are connected via the rotating mechanism 300 and the pivot joint 1. With the rotating mechanism 300 and the pivot joint 1, the upper oscillating body 200 can oscillate about an oscillation axis AX with respect to the lower traveling body 100.

[0013] The upper swing body 200 is provided with a hydraulic pump 202 and a hydraulic oil tank 203. The lower traveling body 100 is provided with a hydraulic motor 102. The hydraulic pump 202 and the swing joint 1 are coupled via pipes 201. The swing joint 1 and the hydraulic motor 102 are coupled via pipes 101. The hydraulic oil tank 203 stores hydraulic oil. The hydraulic oil stored in the hydraulic oil tank 203 is supplied to the hydraulic pump 202 via an oil path 204. The hydraulic pump 202 discharges the hydraulic oil supplied from the hydraulic oil tank 203. The hydraulic oil discharged from the hydraulic pump 202 is supplied to the hydraulic motor 102 via the pipes 201, an oil path 30 provided in the swing joint 1, and the pipes 101. When the hydraulic oil discharged from the hydraulic pump 202 is supplied to the hydraulic motor 102 and the hydraulic motor 102 is driven, the lower traveling body 100 moves.The hydraulic oil supplied from the hydraulic motor 102 is returned to the hydraulic oil tank 203 via an oil path (not shown).

[0014] The rotation mechanism 300 connects the lower traveling body 100 and the upper oscillating body 200. The rotation mechanism 300 includes an inner ring member 301 and an outer ring member 302. The outer ring member 302 is arranged around the inner ring member 301. The inner ring member 301 and the outer ring member 302 rotate relative to each other about the oscillation axis AX. The inner ring member 301 is attached to the lower traveling body 100. The outer ring member 302 is attached to the upper oscillating body 200. <schwenkgelenk>

[0015] Fig. 2 is a side cross-sectional view illustrating the swing joint according to the embodiment. The swing joint 1 connects the lower traveling body 100 and the upper swing body 200. The swing joint 1 includes a rotor 10 and a shaft 20 rotatably supported on the rotor 10. The rotor 10 and the shaft 20 rotate relative to each other about the swing axis AX. The rotor 10 is fixed to the lower traveling body 100. The shaft 20 is fixed to the upper swing body 200. The rotor 10 may be fixed to the upper swing body 200, and the shaft 20 may be fixed to the lower traveling body 100.

[0016] A hydraulic oil flow path 22 extending in the axial direction is provided inside the shaft 20 of the swivel joint 1. A pipe 21 is arranged within the hydraulic oil flow path 22. A space between the hydraulic oil flow path 22 and the pipe 21 can also be used as a flow path for the hydraulic oil. In the embodiment, the hydraulic oil is coupled to a drain circuit that returns from the hydraulic motor 102 to the hydraulic oil tank 203. The pipe 21 is hollow and tubular. The pipe 21 is made of, for example, a conductive material such as a metal. A cable for supplying electrical power from the power supply unit 50 of a power supply system 5 to the lower traveling body 100 is inserted into the pipe 21. The pipe 21 is coupled to a lower portion 11 of the rotor 10 of the swivel joint 1 in a state in which a lower end portion of the pipe 21 is opened.The cable inserted into the tube 21 is led out of the lower end portion of the tube 21. The led-out cable supplies electrical power to the lower traveling body 100. <Energiezuführsystem>

[0017] Fig. 3 is a side cross-sectional view illustrating the power supply unit according to the embodiment. Fig. 4 is a perspective view illustrating the power supply unit according to this embodiment. Fig. 5 is a schematic diagram illustrating the power supply unit according to this embodiment. The power supply system 5 supplies electrical power to the lower traveling body 100. The power supply system 5 includes a non-contact power supply unit (hereinafter referred to as the "power supply unit") 50 and a sensor interface (IF) controller (hereinafter referred to as the "controller") 60. <Energiezuführeinheit>

[0018] The power supply unit 50 supplies electrical power contactlessly from the upper side of the oscillating body 200 to the lower side of the traveling body 100. The power supply unit 50 is mounted on an upper portion of the pivot joint 1. The power supply unit 50 includes a DC / DC converter 51, an oscillation circuit 52, a rotary transformer 53, a smoothing circuit 54, and a rotation sensor 55.

[0019] The DC / DC converter 51 outputs the electrical power supplied from the upper vibrating body 200 side to the vibrating circuit 52. For example, the DC / DC converter 51 converts the supplied DC power of 24 [V] into a DC power of 5 [V] and outputs the DC power. In the embodiment, the DC / DC converter 51 is arranged on a vibrating circuit board located above the rotation sensor 55. In the embodiment, the DC / DC converter 51 is arranged on an upper portion of a main body portion 591. In the embodiment, the DC / DC converter 51 is arranged above the rotation sensor 55 and a magnet portion 56.

[0020] The oscillation circuit 52 is coupled to the upper oscillating body 200, converts electrical energy into alternating current, and supplies the alternating current to the rotary transformer 53. The oscillation circuit 52 converts the direct current supplied from the DC / DC converter 51 into a high-frequency alternating current. The oscillation circuit 52 outputs the alternating current to the rotary transformer 53. In the embodiment, the oscillation circuit 52 is arranged on the oscillation circuit board above the rotation sensor 55. In this embodiment, the oscillation circuit 52 is arranged on the upper portion of the main body portion 591. In this embodiment, the oscillation circuit 52 is arranged above the rotation sensor 55 and the magnet portion 56.

[0021] The rotary transformer 53 is coupled to the upper vibrating body 200 and the lower traveling body 100. The rotary transformer 53 is arranged coaxially with a rotation axis AX of the swing joint 1. A central portion of the rotary transformer 53 is hollow, and a small-diameter portion, which is a shaft portion of a rotary shaft 592 coaxial with the rotation axis AX of the swing joint 1, is passed through it. In the embodiment, the rotary transformer 53 is arranged below the vibration circuit 52. In the embodiment, the rotary transformer 53 is arranged below the rotation sensor 55 and the magnet portion 56. In the embodiment, the rotary transformer 53 is arranged above the smoothing circuit 54. In this embodiment, an upper portion of the rotary transformer 53 is arranged on the main body portion 591 fixed to the upper side of the vibrating body 200.In this embodiment, the upper portion of the rotary transformer 53 protrudes upward from a large-diameter portion of the rotary shaft 592. In this embodiment, a lower portion of the rotary transformer 53 is disposed in the large-diameter portion of the rotary shaft 592. In this embodiment, the lower portion of the rotary transformer 53 rotates with the rotary shaft 592 when the pivot joint 1 rotates about the rotation axis AX.

[0022] The smoothing circuit 54 is coupled to the lower traveling body 100 and converts the alternating current supplied from the rotary transformer 53 into a direct current. The smoothing circuit 54 supplies a direct current of approximately 10 [V] or more and 15 [V] or less to the lower traveling body 100 side. In the embodiment, the smoothing circuit 54 is arranged on a smoothing circuit board located below the rotary transformer 53. In the embodiment, the smoothing circuit 54 is arranged above a spring 545. In the embodiment, the smoothing circuit 54 is arranged above the tube 21 located inside a mounting shaft 595 and the shaft 20 of the pivot joint 1.

[0023] An electrode on a negative side of the smoothing circuit 54 is electrically connected to a housing of the lower traveling body 100. An electrode on the positive side of the smoothing circuit 54 is led out of a lower portion of the pivot joint 1 via a cable that is guided in the axial direction through the pipe 21 provided in the pivot joint 1.

[0024] A mounting plate 542, a mounting plate 544, the spring 545, a crimp terminal 546 and a spring 547 are formed of, for example, a conductive material such as a metal.

[0025] The mounting plate 542 is arranged above the mounting plate 544 in the axial direction. The mounting plate 544 is arranged below the mounting plate 542 in the axial direction. The mounting plate 542 and the mounting plate 544 are arranged to face each other while being spaced apart in the axial direction. The mounting plate 542 and the mounting plate 544 clamp the spring 545 in the axial direction. The mounting plate 542, the mounting plate 544, and the spring 545 are electrically coupled.

[0026] The spring 545 is electrically coupled to the electrode on the positive side of the smoothing circuit 54 and transmits a positive voltage. The spring 545 is electrically coupled to the mounting plate 542, the mounting plate 544, and the crimp terminal 546. In the embodiment, the spring 545 is clamped between the mounting plate 542 and the mounting plate 544. In the embodiment, the spring 545 is arranged below the smoothing circuit board on which the smoothing circuit 54 is arranged. In the embodiment, the spring 545 is arranged above the tube 21 provided inside the mounting shaft 595 and the shaft 20 of the pivot joint 1.

[0027] The spring 545 is mounted on the rotary shaft 592 and the mounting shaft 595 in a state where it is clamped between the mounting plate 542 and the mounting plate 544 in the axial direction.

[0028] The crimp terminal 546 is the positive-side electrode of the smoothing circuit 54. The crimp terminal 546 is attached to the mounting plate 544. The crimp terminal 546 is electrically coupled to the mounting plate 544. The crimp terminal 546 is electrically coupled to the cable inserted into the tube 21 inside the shaft 20 of the swivel joint 1. The surface of the cable is coated with an insulating material. In the embodiment, the crimp terminal 546 is arranged in an intermediate portion between the mounting plate 542 and the mounting plate 544.

[0029] The spring 547 is electrically coupled to the negative-side electrode of the smoothing circuit 54 and transmits a negative voltage (ground voltage). The spring 547 is fixed to an outer peripheral surface of the rotating shaft 592 and an outer peripheral surface of the mounting shaft 595. The spring 547 is electrically coupled to the rotating shaft 592 and the mounting shaft 595. In the embodiment, the spring 547 is arranged below the smoothing circuit board on which the smoothing circuit 54 is arranged. In the embodiment, the spring 547 is arranged above the tube 21 located inside the mounting shaft 595 and the shaft 20 of the pivot joint 1.

[0030] The mounting plate 542 is fixed with a resin screw (not shown) to a copper foil portion (not shown) exposed on a bottom surface of the smoothing circuit board on which the smoothing circuit 54 is arranged. As a result, the copper foil portion on the bottom surface of the smoothing circuit board and the mounting plate 542 come into contact with each other and are electrically coupled. The electrical power from the smoothing circuit 54 flows via the mounting plate 542, the spring 545, and the crimp terminal 546 to the cable passed through the tube 21 inside the shaft 20 of the swivel joint 1.

[0031] An insulating portion 541 and an insulating portion 543 are formed of a glass epoxy material. The insulating portion 541 and the insulating portion 543 are arranged to face each other while being spaced apart from each other in the axial direction. The insulating portion 541 is arranged in surface contact with an upper surface of the mounting plate 542. The insulating portion 543 is in surface contact with a lower surface of the mounting plate 544. The insulating portion 541 and the insulating portion 543 clamp the mounting plate 542, the mounting plate 544, the spring 545, and the crimp terminal 546 in the axial direction. The insulating portion 541 electrically isolates the smoothing circuit 54 from the mounting plate 542, the spring 545, and the crimp terminal 546. The insulating portion 543 electrically isolates the mounting plate 544, the spring 545, and the crimp terminal 546 from the mounting shaft 595.

[0032] The rotation sensor 55 is a sensor that detects a rotation angle of the rotation axis AX of the swivel joint 1. In the embodiment, the rotation sensor 55 is arranged below the oscillation circuit 52 and above the rotary transformer 53. The rotation sensor 55 is arranged above the tube 21 located inside the shaft 20 of the swivel joint 1. The rotation sensor 55 is arranged coaxially with the rotation axis AX of the swivel joint 1. The rotation sensor 55 is arranged at an upper end portion of the rotary shaft 592, which is coaxially arranged via the mounting shaft 595 at an upper portion of the shaft 20 of the swivel joint 1. The rotation sensor 55 receives electrical power from a main controller arranged in the upper oscillating body 200 via a cable and outputs sensor data to the main controller via the cable. The rotation sensor 55 has a magnet portion 56. The magnet portion 56 is arranged at the upper end portion of the rotary shaft 592.The magnet section 56 rotates together with the shaft 20 of the pivot joint 1 around the rotation axis AX. A relative angle of rotation between the magnet section 56 and the rotation sensor 55 is detected by a Hall element of the rotation sensor 55.

[0033] The main body portion 591, the rotary shaft 592, a bushing 593a, a bushing 593b, a cover portion 594, and the mounting shaft 595 are formed of, for example, a conductive material such as a metal material.

[0034] The main body portion 591, together with the cover portion 594, defines the external shape of the power supply unit 50. The main body portion 591 is tubular. The DC / DC converter 51, the oscillation circuit 52, the rotary transformer 53, the smoothing circuit 54, and the rotation sensor 55 are housed in the main body portion 591. The rotary shaft 592 and the mounting shaft 595 are arranged within the main body portion 591.

[0035] The rotary shaft 592 is arranged inside the main body section 591. The rotary shaft 592 is arranged on the upper portion of the shaft 20 of the swivel joint 1 coaxially with the rotation axis AX via the mounting shaft 595. The rotary shaft 592 rotates together with the shaft 20 of the swivel joint 1 about the rotation axis AX. In the rotary shaft 592, the large diameter portion and the small diameter portion are integrally formed in the axial direction. The large diameter portion of the rotary shaft 592 is directed axially downward. The lower portion of the rotary transformer 53 and the smoothing circuit 54 are arranged in the large diameter portion of the rotary shaft 592. The small diameter portion of the rotary shaft 592 is a shaft portion coaxial with the rotation axis AX of the swivel joint 1. The small diameter portion of the rotary shaft 592 is directed axially upward.The rotary transformer 53 is arranged in the small diameter portion of the rotary shaft 592.

[0036] The rotary shaft 592 is fixed with screws to the smoothing circuit board on which the smoothing circuit 54 is arranged. The rotary shaft 592 is fixed with a resin screw (not shown) to a copper foil portion (not shown) exposed on a top surface of the smoothing circuit board. As a result, the copper foil portion on the top surface of the smoothing circuit board and the rotary shaft 592 come into contact with each other and are electrically coupled.

[0037] The bushing 593a and the bushing 593b are formed of a metallic material. The bushing 593a is formed of a plate material in the shape of a disc. The bushing 593a is inserted between the main body portion 591 and the upper portion of the rotary shaft 592. The bushing 593a is arranged to cover the upper surface of the large-diameter portion of the rotary shaft 592. The bushing 593b is formed of a plate material in a cylindrical shape. The bushing 593b is arranged between the main body portion 591 and a radially outer side of the rotary shaft 592. The bushing 593a is arranged to cover the radially outer side of the rotary shaft 592 of the rotary shaft 592. The bushing 593a and the bushing 593b are electrically connected to the main body portion 591 and the rotary shaft 592.

[0038] The cover portion 594, together with the main body portion 591, defines an outer shape of the power supply unit 50. The cover portion 594 is arranged on the upper portion of the main body portion 591.

[0039] The mounting shaft 595 is a shaft for mounting the power supply unit 50 to the tube 21 located inside the shaft 20 of the pivot joint 1. The mounting shaft 595 mounts the power supply unit 50 to the upper portion of the tube 21 located inside the shaft 20 of the pivot joint 1. The mounting shaft 595 is arranged below the rotating shaft 592. <steuerung>

[0040] A controller 60 is arranged in the lower traveling body 100. The controller 60 is a work equipment controller that controls various functions of the lower traveling body 100 of the work vehicle MV. The controller 60 includes a power supply circuit 61, a general-purpose microcomputer (MCU: Micro Controller Unit) 62, a sensor power supply output 63, a general-purpose analog interface 64, a switching circuit 65, a general-purpose digital interface 66, a Controller Area Network (CAN) driver 67, a sensor 68, and a radio chip 69. The configuration of the controller 60 is an example and is not limited thereto.

[0041] The power supply circuit 61 is supplied with a direct current of approximately 10 [V] or more and 15 [V] or less from the smoothing circuit 54 of the power supply unit 50. The power supply circuit 61 supplies electrical power to each unit of the controller 60.

[0042] The MCU 62 is a general-purpose microcontroller. The MCU 62 is coupled to the general-purpose analog interface 64 and the general-purpose digital interface 66 for data transfer. In this embodiment, the general-purpose analog interface 64 and the general-purpose digital interface 66 contain multiple channels.

[0043] The sensor power supply output 63 outputs a direct current of about 5 [V] to the sensor 68 and the like arranged in the lower traveling body 100.

[0044] The CAN driver 67 is a driver for communicating data with sensors arranged in the lower body 100 via the CAN.

[0045] The sensors 68 are various sensors arranged in the lower body 100. For example, the sensor 68 is a sensor that detects an abnormality in the lower body 100. The sensor 68 is a sensor that detects a vibration in the lower body 100.

[0046] The wireless chip 69 communicates data using a wireless standard such as ZigBee (registered trademark) or TWELITE (registered trademark). In this embodiment, the wireless chip 69 wirelessly transmits sensor data to the main controller in the upper oscillating body 200. <betrieb>

[0047] The operation of the power supply unit 50 configured as described above, particularly the flow path of the electric power supplied to the lower traveling body 100 by the power supply unit 50, will be described with reference to Fig. 4 described.

[0048] A current flow path A1 is a current flow path for a positive voltage in the smoothing circuit 54. The current flow path A1 is a flow path of a current of a positive voltage taken from the lower portion 11 of the pivot joint 1 via the mounting plate 542, the spring 545, the crimp terminal 546 and the cable from the smoothing circuit 54.

[0049] A current flow path A2 is a current flow path of a negative voltage in the smoothing circuit 54. The current flow path A2 is a flow path of a current of a negative voltage flowing into the smoothing circuit 54 via the tube 21 of the pivot joint 1, the mounting shaft 595, the spring 547, and the rotating shaft 592.

[0050] A current flow path A3 is another current flow path of a negative voltage in the smoothing circuit 54. The current flow path A3 is a current flow path of a negative voltage flowing into the smoothing circuit 54 via the pivot joint 1, the main body portion 591, the bushing 593a, the bushing 593b, and the rotary shaft 592. <wirkungen>

[0051] As described above, according to the embodiment, the electrode on the negative side of the smoothing circuit 54 is electrically coupled to the housing of the lower traveling body 100. According to the embodiment, the electrode on the positive side of the smoothing circuit 54 is led out from the lower portion 11 of the pivot joint 1 via the cable that is passed through the pipe 21 inside the pivot joint 1 in the axial direction. Therefore, according to the embodiment, a single-core cable can be arranged inside the pivot joint 1. For example, if a cable hole is provided inside the pivot joint 1, the cross-sectional area occupied by the cable can be made smaller than that of a two-core cable. According to this embodiment, it is possible to reduce the influence on the wall thickness of the hydraulic oil flow path 22 of the pivot joint 1 and minimize a decrease in the strength of the pivot joint 1.Specifically, assuming that the diameter of the two-core cable is Φ2d, the diameter of the single-core cable is Φd or less, and the cross-sectional area is 1 / 4 times. According to the embodiment, the number of cores of the cable can be reduced. According to this embodiment, the swivel joint 1 can be made smaller and more cost-effective. As described above, the embodiment can suppress a reduction in the area of ​​the hydraulic oil flow 22 of the swivel joint 1 and minimize an increase in pressure loss. The embodiment can suppress a decrease in the strength of the swivel joint 1.

[0052] In the embodiment, the rotary transformer 53 can be arranged coaxially with the rotation axis AX of the pivot joint 1. In the embodiment, the rotary transformer 53 can be arranged at a suitable location.

[0053] In the embodiment, the rotation sensor 55 that detects the rotation of the pivot joint 1 can be arranged. In the embodiment, it is possible to transmit electrical power to the lower traveling body 100 side and detect the rotation of the pivot joint 1.

[0054] In the embodiment, the rotation sensor 55 can be arranged coaxially with the rotation axis AX of the pivot joint 1. In the embodiment, the rotation sensor 55 can be arranged at a suitable location.

[0055] In this embodiment, the smoothing circuit 54 may be arranged below the rotary transformer 53. In this embodiment, the smoothing circuit 54 may be arranged at a suitable location. According to this embodiment, the lower side of the traveling body 100 may be supplied with electrical power via a single-core cable.

[0056] In the embodiment, the rotary transformer 53 may be arranged below the oscillation circuit 52. In the embodiment, the rotary transformer 53 may be arranged at a suitable location.

[0057] In the embodiment, the rotation sensor 55 may be arranged below the oscillation circuit 52 and above the rotary transformer 53. In the embodiment, the rotation sensor 55 may be arranged at a suitable location. <modifikation>

[0058] The arrangement of the rotary transformer 53 and the rotation sensor 55 in the power supply unit 50 is not limited to the above. The rotary transformer 53 may be arranged above the rotation sensor 55. List of reference symbols 1 SWIVEL JOINT 5 ENERGY SUPPLY SYSTEM 10 ROTOR 20 WAVE 21 PIPE 22 HYDRAULIC OIL FLOW PATH 30 OIL WAY 50 CONTACTLESS ENERGY SUPPLY UNIT (ENERGY SUPPLY UNIT) 51 DC / DC CONVERTERS 52 Oscillation Circuit 53 ROTARY TRANSFORMER 54 SMOOTHING CIRCUIT 55 ROTATION SENSOR 56 MAGNET SECTION 60 SENSOR INTERFACE CONTROL (CONTROL) 61 POWER SUPPLY CIRCUIT 62 universal microcomputers (MCUs) 63 SENSOR POWER SUPPLY FOR HOUSE OUTPUT 64 ANALOG UNIVERSAL INTERFACE 65 Switching 66 DIGITAL UNIVERSAL INTERFACE 67 CAN DRIVERS 68 SENSOR 69 RADIO CHIP 100 LOWER DRIVE BODY 101 PIPE 102 HYDRAULIC MOTOR 200 UPPER OSCILLATING BODY 201 PIPE 202 HYDRAULIC PUMP 203 HYDRAULIC OIL TANK 204 OIL WAY 300 ROTARY MECHANISM 301 INNER RING ELEMENT 302 OUTER RING ELEMENT 541 INSULATION SECTION 542 MOUNTING PLATE 543 INSULATION SECTION 544 MOUNTING PLATE 545 SPRING 546 CRIMP TERMINAL 547 FEATHER 591 MAIN BODY SECTION 592 ROTATING SHAFT 593a SOCKET 593b SOCKET 594 COVER SECTION 595 MOUNTING SHAFT AX SWIVEL AXIS MV WORK VEHICLE QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP S63-266292 A

[0003] < / modifikation> < / wirkungen> < / betrieb> < / steuerung> < / schwenkgelenk> < / arbeitsfahrzeug>

Claims

[1] Energy supply unit mounted on a swivel joint of a work vehicle, the energy supply unit comprising: a rotary transformer coupled to an upper oscillating body and a lower traveling body of the work vehicle; an oscillation circuit coupled to the upper oscillating body, converting electrical energy into an alternating current and supplying the alternating current to the rotary transformer; and a smoothing circuit coupled to the lower traveling body and converting the electrical energy output from the rotary transformer into a direct current, wherein an electrode on a negative side of the smoothing circuit is electrically coupled to a housing of the lower traveling body, and an electrode on the positive side of the smoothing circuit is led out of the lower section of the swivel joint via a cable which is guided in the axial direction through a tube provided inside the swivel joint. [2] Energy supply unit according to claim 1, wherein the rotary transformer is arranged coaxially to a rotation axis of the pivot joint. [3] The energy supply unit according to claim 1, further comprising: a rotation sensor that detects the rotation of the swivel joint. [4] Energy supply unit according to claim 3, wherein the rotation sensor is arranged coaxially to a rotation axis of the pivot joint. [5] The power supply unit according to claim 1, wherein the smoothing circuit is arranged below the rotary transformer. [6] The power supply unit according to claim 5, wherein the rotary transformer is arranged below the oscillation circuit. [7] The power supply unit according to claim 4, wherein the rotation sensor is arranged below the oscillation circuit and above the rotary transformer. [8] Swivel joint, comprising: the energy supply unit according to one of claims 1 to 7; a rotor; a shaft arranged in a bore of the rotor; and a hydraulic oil flow path provided within the shaft in an axial direction.

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