KR20180075754A - Small hydraulic system integrated with motor and pump and built-in hydraulic curcuit - Google Patents

Abstract

The present invention relates to a small hydraulic power generator having a motor and a pump integrated with each other and embedded therein with a hydraulic circuit for direct hydraulic control. More specifically, the present invention relates to a small hydraulic power generator having a motor and a pump integrated with each other and embedded therein with a hydraulic circuit for direct hydraulic control, which includes: an electric motor unit, which includes an electric motor to generate electric power; a hydraulic piston pump unit, which includes a piston pump including an output port, receives the electric power, and generates hydraulic power; a hydraulic oil discharge port, which is used for applying hydraulic oil for the hydraulic power to an actuator; a hydraulic pressure passage, which is used for transferring the hydraulic oil from the output port to the hydraulic oil discharge port; a power transform unit, which converts the electric power having high revolutions per minute (RPM)-low torque into electric power having low RPM-high torque and applies the converted result to the hydraulic piston pump unit; and a case unit having the electric motor unit, the hydraulic piston pump, the hydraulic passage, and the power transform unit arranged therein and sealed and including a power-control line connector for applying driving power and a control signal.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a small-sized hydraulic power generating device having a motor and a pump integrated with each other,

The present invention relates to a small-sized hydraulic power generator in which a motor and a pump are integrated and a hydraulic circuit for direct oil control is incorporated. More specifically, the present invention relates to a control apparatus for a hydraulic power generation apparatus, which uses a hydraulic pump to secure an output of a required size and, instead of a complicated control system used in a general hydraulic power generation apparatus, The present invention relates to a small-sized hydraulic power generator including a motor and a pump integrated in one body by integrating a hydraulic pump and an electric motor in one body, and a hydraulic circuit for direct oil control.

The robotic industry has been expanding rapidly, as well as its numerical aspects. It is applied to various automation production equipments, it is the basis of the mass production industry, and it is developed for the purpose of putting it into work for human being in extreme situations such as a disaster scene.

Instead of the traditional all-weather moving means, a quadruped walking robot using four-legged walking animals and its gait mechanism, fishes using tail fin moving from side to side, Robot diving robot, which has been focused on implementation of specific functions in many fields, such as "submersible submersible robot", which is merely a "machine faithful to its function", is now able to perform various functions most effectively, It is being developed to resemble life.

Especially, in recent years, the development of machine and control systems of humanoid robots, which simulate human contours, has been actively developed. In addition, when artificial intelligence technology, which catches up to human brains at the speed of technological development, , A bipedal walk with human contours, and the movement of human sophisticated arms and hands, will replace the work of human beings.

In order to improve the efficiency of the robot system in various ways, it is necessary to provide a drive system capable of precise control with the required output. Although a driving system is essential for 'motion', an efficient artificial driving system that is comparable to a driving system provided by an organism has not been developed. A mechanical drive system that is comparable to a drive system that occupies a physically small volume, but with tremendous power and speed, has not yet come to fruition.

Currently, the driving system used in general robotic devices is a hydraulic actuator, which uses the principle of Pascal's principle of "the pressure applied to the incompressible fluid contained in the enclosed container is delivered at the same magnitude to all points of the fluid" to be.

Fig. 1 shows components of a general hydraulic device. As can be seen from FIG. 1, a general hydraulic pressure apparatus can be roughly classified into a hydraulic pressure generating unit, a hydraulic pressure control unit, and a hydraulic pressure driving unit. The hydraulic pressure generating portion is a portion that generates hydraulic pressure, and may be constituted by an electric motor or a motor which is an energy generating device of the entire apparatus, a hydraulic pump which generates hydraulic pressure using the energy, and other accessories.

The hydraulic pressure generated in the hydraulic pressure generating unit is controlled by the hydraulic pressure control unit, and the magnitude, direction, and speed of the hydraulic pressure are applied to the hydraulic driving unit that performs the mechanical operation. Such a current hydraulic device can generate a large force that can be applied to an excavator, a crane and the like which require a high output, and occupies most of the drive systems applied to current middle and large sized industrial robot apparatuses.

However, such a hydraulic device is not only complicated in its structure, but also has a limit in miniaturization because the volume of the hydraulic control part, which is a key component for controlling hydraulic energy, is large.

On the other hand, in the case of a small robot system that simulates the outline of an organism such as an animal robot or a humanoid robot as described above, a force suitable for a working field is required rather than a force of force. In other words, in the evolution stage of tens of millions of years, it is necessary to use enough force to effectively use the most effective external structure adopted by the organism. By combining this external structure and force, It is possible to apply the present invention to a robot system capable of more complicated operations.

Therefore, instead of using a complicated control system used in a general hydraulic power generator, it is possible to directly control the flow rate of hydraulic oil by using an electric motor capable of relatively precise control, If a hydraulic power generation device that integrates an electric motor and miniaturize it is developed, it is expected to be very usefully applied to various robot systems in the future.

Korean Patent Publication No. 10-2004-0031433

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and it is an object of the present invention to provide a hydraulic power generating apparatus, . In addition, in the process of transferring energy from the motor unit 100, which is a mechanical energy generating apparatus, to the pump unit 300, which is a hydraulic energy generating apparatus, the magnitude of a force, which is a major component of energy, It is possible to integrate a motor and a pump that can be miniaturized as compared with the conventional high output hydraulic pressure generating apparatus and to provide a compact hydraulic pressure control system with a built-in hydraulic circuit for direct oil control Power generator

It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are not intended to limit the invention to the precise form disclosed. It can be understood.

A first object of the present invention is to provide an electric motor including an electric motor and generating an electric power; A hydraulic piston pump unit including a piston pump having an output port and receiving the electric power to generate hydraulic power; A hydraulic oil discharge port for applying the hydraulic oil by the hydraulic power to the actuator; A hydraulic pressure passage for transferring the hydraulic oil from the output port to the hydraulic oil discharge port; A power conversion unit for converting the electric power having a high RPM to a low torque into a low RPM-high torque and applying the electric power to the hydraulic piston pump, and an electric motor unit, A motor including a case portion having a power source-control line connector for applying a driving power source and a control signal, and a pump are integrated and a hydraulic circuit for direct hydraulic control is incorporated And can be achieved by providing a small hydraulic power generation device.

Further, the electric motor may be a BLDC (Brushless DC) motor.

The pump unit may be a bidirectional swash plate type piston pump structure.

In addition, the piston pump unit may include a pump case drain port.

The case drain port is connected to the hydraulic pressure passage through a check valve to form a hydraulic pressure-drain connection portion, and the check valve controls the hydraulic oil flowing out from the case drain port.

Further, the power converting unit may include a planetary gear reducer structure.

The power conversion unit may include a rotation angle sensor that measures the number of revolutions of the pump shaft, and controls the number of revolutions of the electric motor based on the number of revolutions of the shaft.

The hydraulic control circuit may further include an encoder or an electric speed controller (ESC) for controlling the number of revolutions of the BLDC motor.

The pressure sensor may further include a pressure sensor disposed adjacent to the hydraulic oil discharge port to measure the pressure to the hydraulic oil pressure.

The accumulator further includes an accumulator and a pilot check valve. The accumulator is connected to the hydraulic passage through the pilot check valve to constitute an accumulator connecting portion in the hydraulic passage. The accumulator connecting portion connects the case drain connecting portion And compensates for different volumes of each of the bidirectional linear hydraulic cylinders of the actuator based on the measured value of the pressure sensor.

The control unit may control the number of rotations of the electric motor based on the pressure measurement value of the hydraulic pressure.

In addition, the power-control line connector may be a waterproof, dustproof, and internal-voltage connector.

According to an embodiment of the present invention, the essential elements of the hydraulic power generation device are all integrated in the case part 500 so as to be integrally formed. In addition, in the process of transferring energy from the motor unit 100, which is a mechanical energy generating apparatus, to the pump unit 300, which is a hydraulic energy generating apparatus, the magnitude of a force, which is a major component of energy, By arranging the apparatus, there is an advantage that the operating pressure required by the joint system of the small-sized robot system is generated, and the miniaturization can be achieved compared with the conventional high-output hydraulic pressure generating apparatus.

It should be understood, however, that the effects obtained by the present invention are not limited to the above-mentioned effects, and other effects not mentioned may be clearly understood by those skilled in the art to which the present invention belongs It will be possible.

Figure 1. Components of a typical hydraulic device.
2 is a perspective view of a small hydraulic power generator in which an electric motor and a piston pump according to an embodiment of the present invention are integrated and a hydraulic circuit for direct control of hydraulic pressure is incorporated.
Fig. 3 is a side view of a hydraulic circuit and a hydraulic circuit of a small hydraulic power generating device in which an electric motor and a piston pump according to an embodiment of the present invention are integrated, and a hydraulic circuit for direct control of hydraulic force is incorporated.
4. An encoder arrangement for controlling a BLDC motor applied to a small-sized hydraulic power generating device in which an electric motor and a piston pump according to an embodiment of the present invention are integrated and a hydraulic circuit for controlling hydraulic force is incorporated
5. A three-dimensional perspective view of a power conversion unit of a small-sized hydraulic power generating apparatus in which an electric motor and a piston pump according to an embodiment of the present invention are integrated and a hydraulic circuit for direct control of a hydraulic force is incorporated.
Figure 6 is a three-dimensional perspective view and side cross-sectional view of a pump section of a small hydraulic power generation apparatus in which an electric motor and a piston pump according to an embodiment of the present invention are integrated and a hydraulic circuit for direct control of hydraulic force is incorporated.
Figure 7 is a block diagram of a control flow of a small hydraulic power generator having an electric motor and a piston pump according to an embodiment of the present invention integrated with a hydraulic circuit for direct control of hydraulic force
8 is a conceptual diagram in which a small hydraulic power generation device in which an electric motor and a piston pump according to an embodiment of the present invention are integrated and a hydraulic circuit for direct control of a hydraulic force is incorporated in a hydraulic actuating robot arm

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the detailed description of known functions and configurations incorporated herein will be omitted when it may unnecessarily obscure the subject matter of the present invention.

The same reference numerals are used for portions having similar functions and functions throughout the drawings. Throughout the specification, when a part is connected to another part, it includes not only a case where it is directly connected but also a case where the other part is indirectly connected with another part in between. In addition, the inclusion of an element does not exclude other elements, but may include other elements, unless specifically stated otherwise.

Hereinafter, the structure and function of a hydraulic power generator using a swash plate type bidirectional piston pump according to an embodiment of the present invention will be described.

2 is a perspective view of a small hydraulic power generator in which an electric motor and a piston pump according to an embodiment of the present invention are integrated and a hydraulic circuit for direct control of a hydraulic force is incorporated.

2, the small hydraulic power generator according to the embodiment of the present invention includes a hydraulic hose connector 520 and a waterproof / dustproof / A connector 530, and the like.

The hydraulic hose connector 520 is a connector for connecting a hydraulic hose for exchanging hydraulic oil between the small hydraulic power generator according to the present invention and an external actuator. The waterproof / vibration-proof / pressure-resistant connector 530 is a port for connecting a control signal line and a power supply line used in an electric motor, a control circuit, a sensor, etc., mounted in the case portion. The use of a robot system to which a hydraulic power generator is applied It can be equipped with waterproof / dustproof / withstand voltage function for stable transmission of power and signal regardless of environment.

The pressure sensor 540 measures the pressure of the hydraulic path 400 and the boosting port is a port connected to a boosting system for maintaining the initial pressure in the hydraulic pressure generator according to the present invention.

FIG. 3 shows a hydraulic circuit diagram and a side sectional view of a small hydraulic power generator in which an electric motor and a piston pump according to an embodiment of the present invention are integrated and a hydraulic circuit for direct control of hydraulic pressure is incorporated. 3, a small hydraulic power generator according to an embodiment of the present invention includes a motor unit 100, a power conversion unit 200, a pump 300, and a hydraulic circuit 400 And is disposed inside the case part 500.

The motor unit 100 receives external electrical energy to generate mechanical energy, and the power converting unit 300 converts the magnitude of the mechanical energy generated in the motor unit and applies the mechanical energy to the pump unit. The pump 300 converts the applied mechanical energy into hydraulic energy using a plurality of piston reciprocating motions. The hydraulic operating fluid pressurized / depressurized by the pump is transferred through the hydraulic passage 400 and flows into the cylinder of the external actuator of the case unit 500.

2 to 3, the small hydraulic power generator according to the embodiment of the present invention integrates all the essential elements of the hydraulic power generator in the case part 500, thereby manufacturing the hydraulic power generator in one piece. In addition, in the process of transferring energy from the motor unit 100, which is a mechanical energy generating apparatus, to the pump unit 300, which is a hydraulic energy generating apparatus, the magnitude of a force, which is a major component of energy, By arranging the apparatus, it is possible to reduce the operating pressure as compared with the conventional high output hydraulic pressure generating apparatus, while generating operating pressure required by the joint system of the small robot system.

As shown in FIG. 3A, the flow rate generated by the hydraulic pump is transmitted to the linear actuator through the check valve 401 and the pilot check valve 402. The hydraulic pump employs a bidirectional piston pump, and an input / output port corresponding to each compression / suction stroke is formed. Further, by transmitting the pump case pressure to the hydraulic circuit again and constituting the hydraulic circuit as a closed circuit, accuracy and controllability of force control of the hydraulic pressure can be secured.

Since the volumes of the bidirectional hydraulic cylinders of the linear actuators are different from each other, it is possible to compensate them using the accumulator 403 and the pilot check valve. As shown in the hydraulic circuit diagram, the pressure sensor is installed in the oil pressure passage 400 to measure the pressure change of the oil pressure passage 400 according to the change in the cylinder volume of the actuator. Based on this, To compensate for the pressure.

A hydraulic pressure line including a check valve and a pilot check valve is formed inside the first and second manifolds shown in FIG. 3B.

FIG. 4 is a diagram showing an arrangement of an encoder for controlling a BLDC motor applied to a small hydraulic power generator in which an electric motor and a piston pump according to an embodiment of the present invention are integrated, and a hydraulic circuit for direct control of hydraulic pressure is incorporated. Respectively. Various types of electric motors applicable to the motor unit 100 can be used, and preferably a small BLDC (brushless DC, 111) motor can be used.

Since BLDC motors are less mechanical, they have less noise than brushed motors and are semi-permanent because they have no wear. In addition, energy loss is small and accurate rotation speed control is possible. The BLDC motor uses the attractive force and the repulsive force between the electromagnet and the permanent magnet, which are wound in the form of a coil, and generally includes a sensor motor including a rotor detection sensor such as an encoder or a hall sensor, and a sensorless Motor can be divided into. Since there is no mechanical contact, noise is low and reliability is high, so it can be used semi-permanently. In addition, high-speed miniaturization and weight reduction are possible, and there is no energy loss due to mechanical contact, and magnetic force is used, resulting in low power density and efficiency. In particular, the Sensored motor can determine the number of revolutions according to the number of pulses of DC current pulse considering the number of coils and permanent magnets, and can receive the PRM information of the actual motor from the sensor, There are advantages.

4, the motor unit 100 may include an encoder for controlling the BLDC motor 111 or a motor control unit 120 including an electric speed controller (ESC). The control unit including the encoder can improve the convenience and accuracy of the control unit of the BLDC motor as described above.

Generally, the mechanical energy generated by an electric motor is the rotational kinetic energy of high RPM - low torque. In the power converting unit 200, the high-RPM-low torque mechanical energy is converted into a low RPM-high torque energy to rotate the pump shaft 301.

FIG. 5 is a three-dimensional perspective view of a power converting unit of a small hydraulic power generator in which an electric motor and a piston pump according to an embodiment of the present invention are integrated and a hydraulic circuit for direct control of hydraulic pressure is incorporated. As described above, the power conversion unit 200 converts the mechanical energy of the high RPM-low torque generated in the motor unit into energy of low RPM-high torque.

As shown in FIG. 5, the power converting unit 200 according to an embodiment of the present invention employs a planetary gear reducer using a planetary gear system. The planetary gear reducer, in which the planetary gears rotate around the sun gear, has a very high power transmission rate per unit volume and can transmit several times the power compared to a common gear reducer of the same size. The reduction ratio can be adjusted by adjusting the gear ratio of the gear to be used. It is used for realizing the operating force (0 to 60 bar, less than 40 kg) required for a general miniature robot to which the small hydraulic power generator according to the present invention is applied .

Further, the power conversion unit of the small hydraulic power generator according to one embodiment of the present invention is disposed at the outer side of the apparatus, and when the cover is removed, the shape of the cover is removed so that the maintenance or the gear change of the planetary gear reducer is facilitated Respectively. Further, the rotation angle sensor for measuring the rotational kinetic energy via the planetary gear reducer is further provided, and the proper number of rotations of the electric motor can be controlled based on the measured rotation number.

FIG. 6 shows a three-dimensional arrangement view eh of the pump unit of the small hydraulic power generator in which the electric motor and the piston pump according to the embodiment of the present invention are integrated and the hydraulic circuit for controlling the hydraulic pressure is incorporated.

As shown in FIG. 6, the small hydraulic power generator according to the embodiment of the present invention employs a swash plate type piston pump. The axial type piston pump can be largely divided into a swash plate type and a boss type. The boss shafts have good sealing at high pressure and are more efficient than the swash plate type, but they have a disadvantage that they have a large installation area. The swash plate type is advantageous in that the capacity of the hydraulic oil can be controlled by the inclination angle change of the swash plate, and the inertia moment is small so that high speed control can be performed.

3 to 6, as described above, the small hydraulic power generation apparatus according to an embodiment of the present invention is designed to cope with a low operating pressure (0 to 60 bar) required in small robots in general . When the range of the total operating pressure is narrow, a high resolution is required to control the operating pressure. Accordingly, the BLDC motor, the swash plate type piston pump, and the power conversion unit disposed therebetween, which are employed in one embodiment of the present invention, operate organically so that the reaction speed to the external control is increased and the small hydraulic power generation Device can be implemented.

FIG. 7 is a block diagram illustrating a control flow of a small hydraulic power generator in which an electric motor and a piston pump according to an embodiment of the present invention are integrated and a hydraulic circuit for direct control of hydraulic pressure is incorporated.

As shown in Fig. 7, the hydraulic power generator according to the present invention converts electric energy injected from the outside of the case portion into hydraulic energy that can apply operating oil to the actuator. In the small hydraulic power generation apparatus according to the present invention constructed as shown in FIG. 7, operation can be applied to an actuator using hydraulic oil without a flow rate / pressure control valve by directly controlling the flow rate of the hydraulic oil through an electric motor. , The hydraulic circuit, and the accumulator can be integrated.

FIG. 8 is a conceptual diagram of applying a small hydraulic power generation device having an electric motor and a piston pump integrated with an oil pressure circuit for direct control of oil pressure to a hydraulic operation robot arm according to an embodiment of the present invention.

As shown in FIG. 8, a small hydraulic power generation apparatus according to an embodiment of the present invention is connected to a rotary actuator of a robot arm by a hydraulic hose, and hydraulic fluid is used as hydraulic power of a robot arm. Further, since the hydraulic power generating apparatus according to the present invention can be downsized as compared with the conventional hydraulic power generating apparatus, the hydraulic power generating apparatus can be integrally formed with a rotary type or linear type actuator.

It should be noted that the above-described apparatus and method are not limited to the configurations and methods of the embodiments described above, but the embodiments may be modified so that all or some of the embodiments are selectively combined .

100. Motor section
110. Electric motor 111. BLDC motor 120. Motor control unit
200. Power conversion unit
300. Pump section
301. Pump shaft 302. Swash plate 303. Piston
400. Hydraulic
401. Check valve 402. Pilot check valve 403. Accumulator
500. Case
510. Working fluid discharge port. 520. Hydraulic hose connector 530. Waterproof / dustproof / pressure connector 540 Pressure sensor 550. Boosting port
600. Linear Actuator

Claims (12)

An electric motor part including an electric motor and generating an electric power;
A hydraulic piston pump unit including a piston pump having an output port and receiving the electric power to generate hydraulic power;
A hydraulic oil discharge port for applying the hydraulic oil by the hydraulic power to the actuator;
A hydraulic pressure passage for transferring the hydraulic oil from the output port to the hydraulic oil discharge port;
A power converting unit for converting the electric power of a high RPM-low torque into a low RPM-high torque and applying the torque to the hydraulic piston pump;
And a case portion including a power-control line connector for sealing the electric motor portion, the hydraulic piston pump, the hydraulic pressure passage, and the power conversion portion disposed inside and hermetically closed to apply a driving power and a control signal. And a pump are integrated, and a hydraulic hydraulic power generator with a hydraulic circuit for direct hydraulic control is incorporated. The method according to claim 1,
Wherein the electric motor is a BLDC (Brushless DC) motor. The motor and the pump are integrated, and a hydraulic circuit for direct hydraulic control is incorporated. The method according to claim 1,
Wherein the pump unit is a bidirectional swash plate type piston pump structure. The motor and the pump are integrated, and a hydraulic circuit for direct hydraulic control is incorporated. The method according to claim 1,
Wherein the piston pump unit includes a pump case drain port, and the hydraulic pump is integrated with the hydraulic circuit for direct hydraulic control. 5. The method of claim 4,
The pump case drain port is connected to the hydraulic passage through a check valve to form a hydraulic pressure-drain connection,
And the check valve adjusts the hydraulic oil flowing out from the case drain port, wherein the motor and the pump are integrated, and the hydraulic circuit for direct hydraulic control is incorporated. The method according to claim 1,
Wherein the power converting portion includes a planetary gear reducer structure, wherein the motor and the pump are integrated, and a hydraulic circuit for direct hydraulic control is incorporated. The method according to claim 1,
Wherein the power converting unit includes a rotation angle sensor for measuring the number of revolutions of the pump shaft and controls the number of revolutions of the electric motor based on the number of revolutions of the shaft, wherein the motor and the pump are integrated, Small Hydraulic Power Generator with Integrated Circuit. 3. The method of claim 2,
Further comprising an oil pressure control circuit part including an encoder or an electric speed controller (ESC) for controlling the number of revolutions of the BLDC motor, wherein the motor and the pump are integrated, and the oil pressure control circuit part Hydraulic power generator. 6. The method of claim 5,
Further comprising a pressure sensor provided adjacent to the hydraulic oil discharge port to measure the pressure to the hydraulic pressure, wherein the motor and the pump are integrated, and the hydraulic pressure circuit for hydraulic control is integrated Hydraulic power generator.
10. The method of claim 9,
Further comprising an accumulator and a pilot check valve,
Wherein the accumulator is connected to the hydraulic pressure passage through the pilot check valve to constitute an accumulator connection portion in the hydraulic pressure passage,
Wherein the accumulator connecting portion is located between the case drain connecting portion and the pressure sensor,
Wherein the controller is configured to compensate for different volumes of each of the bidirectional linear hydraulic cylinders of the actuator based on the measured value of the pressure sensor, wherein the motor and the pump are integrated, and the hydraulic hydraulic power generation Device.
10. The method of claim 9,
Wherein the control unit controls the number of revolutions of the electric motor on the basis of the measured pressure value of the hydraulic pressure. The small hydraulic power generation device incorporates a motor and a pump, and incorporates a hydraulic circuit for direct hydraulic control.
The method according to claim 1,
Wherein the power-control line connector is a waterproof, vibration-proof, and pressure-resistant connector, and the hydraulic power circuit is integrated with a hydraulic circuit for direct control of hydraulic pressure.

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