JP2017052318A - Brake driving device and brake system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce energy loss of a brake driving device.SOLUTION: A brake driving device 100 is provided with: a cylinder 21; a drive piston 30 which divides the inside of the cylinder 21 into a first fluid pressure chamber 25 and a second fluid pressure chamber 26; and an actuator 40 which linearly moves the drive piston 30 along an inner peripheral surface of a first cylinder part 22, in which hydraulic fluid is supplied and discharged to and from the first fluid pressure chamber 25 and the second fluid pressure chamber 26 in accordance with movement of the drive piston 30, and the hydraulic fluid is circulated between the first fluid pressure chamber 25 and a brake device 10 to drive the brake device 10 in accordance with the movement of the drive piston 30.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a brake drive device and a brake system.

  Patent Document 1 discloses a brake system including a hydraulic oil supply device that is driven by an electric actuator and supplies hydraulic oil to the outside, and a hydraulic actuator that is operated by the hydraulic oil and applies a force to the brake. This hydraulic oil supply device has a cylinder having a cylindrical internal space filled with hydraulic oil.

JP 2005-8129 A

  The inside of the cylinder of the hydraulic oil supply device disclosed in Patent Document 1 is divided into two chambers by a piston. One of the two chambers is filled with hydraulic oil, while the other chamber is not filled with hydraulic oil. The other chamber is sealed with air inside.

  In this hydraulic oil supply device, when the electric actuator is driven, the piston moves and one chamber filled with the hydraulic oil contracts, whereby the hydraulic oil is supplied to the hydraulic actuator and the brake operates.

  However, when the piston is moved so as to contract the chamber filled with hydraulic oil, the pressure in the other chamber filled with air is reduced due to the expansion of the volume, and thus a negative pressure resistance is generated. Such a pressure drop hinders the movement of the piston for supplying hydraulic oil, and therefore, in the hydraulic oil supply device disclosed in Patent Document 1, energy loss occurs when the brake is operated.

  The present invention has been made in view of the above-described problems, and an object thereof is to reduce energy loss of a brake drive device that drives a brake device.

  A first invention is a brake drive device for driving a brake device that brakes a rotating body, and includes a cylinder, a drive piston that divides the inside of the cylinder into a first fluid pressure chamber and a second fluid pressure chamber, and a drive piston. An actuator that linearly moves along the inner peripheral surface of the cylinder, and the working fluid is supplied to and discharged from the first fluid pressure chamber and the second fluid pressure chamber as the drive piston moves. The brake fluid is driven by circulating a working fluid between the first fluid pressure chamber and the brake device.

  In the first invention, the working fluid is supplied to the second fluid pressure chamber as the working fluid is discharged from the first fluid pressure chamber. As described above, the working fluid is supplied to the second fluid pressure chamber according to the volume to be expanded, so that the pressure drop in the second fluid pressure chamber is prevented and the movement of the drive piston is not hindered.

  The second invention is characterized by further comprising a return spring that biases the drive piston in a direction in which braking of the rotating body by the brake device is released.

  In the second invention, the drive piston is moved by the biasing force of the return spring even when the actuator cannot be driven. Therefore, even when there is a malfunction, the braking of the rotating body by the brake device can be released.

  According to a third aspect of the invention, the actuator includes an electric motor and a ball screw mechanism that converts the rotation of the electric motor into a linear motion of the drive piston.

  In the third invention, when the electric motor rotates, the ball screw mechanism linearly moves the drive piston along the inner peripheral surface of the cylinder.

  According to a fourth aspect of the present invention, there is provided a reservoir that stores the working fluid, a first passage that allows the working fluid to flow between the first fluid pressure chamber and the brake device, and a working fluid between the second fluid pressure chamber and the reservoir. And a second passage through which the water is circulated.

  In the fourth invention, the brake device is driven by causing the working fluid to flow between the first fluid pressure chamber and the brake device through the first passage as the drive piston moves. With the movement of the drive piston, the working fluid is supplied to and discharged from the reservoir through the second passage to the second fluid pressure chamber, so even if the volume of the second fluid pressure chamber increases, the pressure drop is prevented, and the drive piston Movement is not hindered.

  The fifth invention further includes a connection passage connecting the first passage and the second passage, and a check valve provided in the connection passage and allowing only the flow of the working fluid from the second passage toward the first passage. It is characterized by providing.

  According to the fifth invention, even if the working fluid in the first fluid pressure chamber and the first passage is insufficient, the working fluid is replenished through the connection passage. Therefore, in the first fluid pressure chamber and the first passage, Generation of negative pressure can be prevented.

  6th invention is a brake system, Comprising: The brake drive device as described in any one of 1st to 5th invention, a brake device, the rotation detector which detects the rotational speed of a rotary body, 1st Rotation detection so that the pressure detector that detects the pressure in the fluid pressure chamber, the operation amount detector that detects the amount of operation of the operation unit by the operator, and the braking force according to the detection result of the operation amount detector And a controller for controlling the actuator of the brake drive device based on the detection results of the pressure detector and the pressure detector.

  In the sixth aspect of the invention, the controller controls the actuator of the brake drive device based on the detection results of the rotation detector and the pressure detector, so that the brake device exhibits a desired braking force according to the amount of braking operation by the operator. can do.

  According to the present invention, the energy loss of the brake drive device that drives the brake device is reduced.

It is a block diagram of the brake system which concerns on embodiment of this invention, and shows the case where a brake device is a non-braking state. It is a lineblock diagram of the brake system concerning the embodiment of the present invention, and shows the case where a brake device is in a braking state.

  Hereinafter, a brake drive device and a brake system according to embodiments of the present invention will be described with reference to the drawings.

  Below, the brake system 101 and the brake drive device 100 for aircraft which are mounted on a fixed-wing aircraft and brake the wheel 1 as a rotating body will be described.

  The brake system 101 drives the brake device 10 and brakes the wheel 1 according to the operation amount of the brake pedal 2 as an operation unit operated by an operator.

  As shown in FIG. 1, the brake system 101 circulates hydraulic oil between a brake device 10 that brakes the wheel 1 by a brake actuator 11 that expands and contracts by the pressure of the hydraulic oil (working fluid), and the brake actuator 11. And a brake drive device 100 for driving the brake device 10.

  An aircraft wheel 1 is configured by attaching a tire (not shown) to the outer periphery of a wheel (not shown). The wheel is attached to an axle (not shown) via a bearing (not shown). That is, the axle does not rotate even if the wheel rotates.

  The brake device 10 is supplied and discharged from a plurality of rotating discs 12 that rotate together with the wheels 1, a non-rotating disc 13 that is non-rotatably attached to the axle, a brake piston 14 that is pressed against the non-rotating disc 13, and the brake drive device 100. And a brake actuator 11 that advances and retracts the brake piston 14 toward and away from the non-rotating disk 13 by the pressure of hydraulic oil. The brake device 10 presses the brake piston 14 against the non-rotating disk 13 by the brake actuator 11 to bring the rotating disk 12 and the non-rotating disk 13 into contact with each other, and generates a braking force by a frictional force.

  A plurality of rotating disks 12 are provided at predetermined intervals. Non-rotating disks 13 are provided on both surfaces of the rotating disk 12. Therefore, a plurality of non-rotating disks 13 are also provided at a predetermined interval. In the brake device 10, the two rotating disks 12 are disposed between the three non-rotating disks 13. The number of each of the non-rotating disk 13 and the rotating disk 12 is not limited to this, and is arbitrarily set according to the required braking force.

  The rotating disk 12 is formed in a disk shape. The rotating disk 12 is supported on the inner periphery of the wheel and rotates integrally with the wheel 1. The rotating disk 12 is supported so as to be displaceable in the axle direction (left and right direction in FIG. 1) with respect to the wheel, that is, slidable.

  The non-rotating disk 13 is formed in a disk shape. The inner periphery of the non-rotating disk 13 is supported by the axle. The non-rotating disc 13 does not rotate even when the wheel 1 rotates. The non-rotating disk 13 is supported so as to be displaceable in the axle direction, that is, slidable.

  The brake piston 14 is provided to face the non-rotating disk 13 so as to be able to advance and retreat toward the non-rotating disk 13. A plurality of brake pistons 14 are provided on the disk-shaped base plate 15 and are arranged at predetermined intervals in the rotational circumferential direction of the wheel 1. Further, the brake piston 14 is provided with a gap between the brake piston 10 and the non-rotating disk 13 in a non-braking state where the brake device 10 does not generate a braking force. That is, the brake piston 14 is opposed to the non-rotating disc 13 by a predetermined gap. In FIG. 1, two brake pistons 14 are illustrated, but the number of brake pistons 14 is not limited thereto, and may be arbitrarily set according to a required braking force or the like.

  The brake actuator 11 is a hydraulic actuator that expands and contracts when hydraulic oil is supplied to and discharged from a pressure chamber (not shown). The brake actuator 11 extends when the hydraulic oil is supplied to the pressure chamber, and presses the brake piston 14 against the non-rotating disk 13 via the base plate 15. When the hydraulic oil is discharged from the pressure chamber, the brake actuator 11 contracts to separate the brake piston 14 from the non-rotating disk 13.

  The brake drive device 100 includes a housing 20, a cylindrical cylinder 21 formed in the housing 20, a drive piston 30 that partitions the inside of the cylinder 21 into a first fluid pressure chamber 25 and a second fluid pressure chamber 26, and a drive An actuator 40 that slidably moves the piston 30 along the inner peripheral surface of the cylinder 21 and a return spring 50 that biases the drive piston 30 in a direction in which the first fluid pressure chamber 25 expands are provided.

  The cylinder 21 includes a first cylinder portion 22 in which the drive piston 30 is accommodated, a second cylinder portion 23 that opens at an end surface of the housing 20 and has an inner diameter smaller than the inner diameter of the first cylinder portion 22, and the first cylinder portion 22. And an annular step portion 24 formed between the first cylinder portion 23 and the second cylinder portion 23.

  The drive piston 30 slides between the bottom portion 22 </ b> A of the first cylinder portion 22 and the step portion 24 along the inner peripheral surface of the first cylinder portion 22. That is, the stepped portion 24 restricts the drive piston 30 from moving in a predetermined direction or more in the direction of expanding the first fluid pressure chamber 25 (left direction in FIG. 1). As described above, the step portion 24 functions as a restricting portion that can restrict the movement of the drive piston 30 beyond a predetermined level. The drive piston 30 abuts on the stepped portion 24 via a ball nut 44 described later as shown in FIG. 1, but may be directly abutted on the stepped portion 24.

  The fluid pressure chamber defined by the drive piston 30 and the bottom portion 22 </ b> A of the first cylinder portion 22 is the first fluid pressure chamber 25. The fluid pressure chamber formed between the drive piston 30 and the stepped portion 24 in the first cylinder portion 22 and the inside of the second cylinder portion 23 are the second fluid pressure chamber 26. The first fluid pressure chamber 25 and the second fluid pressure chamber 26 are filled with hydraulic oil, respectively.

  The return spring 50 is interposed between the drive piston 30 and the bottom 22A of the first cylinder portion 22 in a compressed state. The return spring 50 biases the drive piston 30 in a direction in which the first fluid pressure chamber 25 expands, in other words, in a direction in which braking by the brake device 10 is released, as will be described later.

  In the housing 20, a first port 25 </ b> A communicating with the first fluid pressure chamber 25, a second port 26 </ b> A communicating with the second fluid pressure chamber 26, and supply / discharge through which hydraulic oil supplied to and discharged from the brake device 10 passes. Port 20A is formed.

  As shown in FIG. 1, the second port 26 </ b> A is formed so as not to be completely blocked by the drive piston 30 and the ball nut 44 even when the movement of the drive piston 30 is restricted by the step portion 24. The Specifically, the second port 26 </ b> A is formed so that at least a part thereof opens to the inner peripheral surface of the second cylinder portion 23. Immediately before the drive piston 30 and the ball nut 44 move toward the stepped portion 24 and contact the stepped portion 24, a part of the second port 26A is closed by the drive piston 30 and the ball nut 44 and the second port 26A is closed. The opening area is reduced. Even in this state, the opening area of the second port 26A is secured by opening at least a part of the second port 26A to the inner peripheral surface of the second cylinder portion 23, and the second port 26A is discharged through the second port 26A. A large resistance is prevented from being imparted to the hydraulic oil. Therefore, the hydraulic oil in the second fluid pressure chamber 26 is smoothly discharged through the second port 26A.

  The supply / discharge port 20A communicates with a pressure chamber of the brake actuator 11 in the brake device 10 through a hydraulic pipe 16 serving as a supply / discharge passage.

  The actuator 40 includes an electric motor 41 attached to the housing 20 and a ball screw mechanism 42 that converts the rotation of the electric motor 41 into a linear motion of the drive piston 30.

  The electric motor 41 rotates an output shaft (not shown) when electric power is supplied. The electric motor 41 has a holding brake 41A that allows and restricts rotation of the output shaft.

  The ball screw mechanism 42 is connected to an output shaft (not shown) of the electric motor 41 and is inserted into the first cylinder portion 22 and the second cylinder portion 23. The ball screw mechanism 42 is screwed into the ball screw 43 and the drive piston 30. And a ball nut 44 fixed to the head. When electric power is supplied to the electric motor 41 and the output shaft rotates, the ball screw 43 rotates together with the output shaft. As the ball screw 43 rotates, the ball nut 44 linearly moves in the axial direction of the ball screw 43 according to the rotation direction. Therefore, the drive piston 30 linearly moves along the inner peripheral surface of the first cylinder portion 22 by rotating the electric motor 41.

  The brake drive device 100 includes an accumulator 51 serving as a reservoir for storing hydraulic oil, a first passage 60 through which hydraulic oil flows between the first fluid pressure chamber 25 and the brake device 10, and a second fluid pressure chamber 26. And a second passage 61 through which hydraulic oil flows between the accumulator 51 and the accumulator 51.

  The accumulator 51 stores the hydraulic oil while accumulating the hydraulic oil by the gas pressure sealed inside. The accumulator 51 is provided inside the housing 20. The storage unit is not limited to the accumulator 51 that stores and stores hydraulic oil, but may be a reservoir or a tank that stores without accumulating pressure.

  The 1st channel | path 60 connects the 1st port 25A and the supply / discharge port 20A, and distribute | circulates hydraulic oil between both. The first fluid pressure chamber 25 communicates with the pressure chamber of the brake actuator 11 through the first port 25A, the first passage 60, the supply / discharge port 20A, and the hydraulic piping 16.

  In addition, the brake driving device 100 includes a connection passage 62 and a relief passage 63 that connect the first passage 60 and the second passage 61, and hydraulic oil that is provided in the connection passage 62 and that travels from the second passage 61 to the first passage 60. A check valve 52 that allows only the flow of the oil, a relief valve 53 that is provided in the relief passage 63 and opens when the pressure in the first passage 60 exceeds the valve opening pressure, and allows hydraulic oil to escape to the second passage 61; Is further provided.

  The connection passage 62 and the relief passage 63 are each formed in the housing 20. Further, the check valve 52 and the relief valve 53 are each provided in the housing 20. As described above, the accumulator 51, the check valve 52, and the relief valve 53 are built in the housing 20, but may be externally attached to the housing 20.

  By providing the connection passage 62 and the check valve 52 in the brake driving device 100, when the hydraulic oil in the first fluid pressure chamber 25 and the first passage 60 is insufficient, the hydraulic oil is supplied from the accumulator 51 through the connection passage 62. To be replenished. Therefore, the generation of negative pressure in the first fluid pressure chamber 25 and the first passage 60 can be prevented.

  The brake system 101 includes a rotation sensor 70 as a rotation detector that detects the rotation speed of the wheel 1, a pressure sensor 71 as a pressure detector that detects the pressure in the first fluid pressure chamber 25, and a brake pedal 2 by an operator. The operation amount sensor 72 as an operation amount detector for detecting the operation amount of the vehicle and the brake based on the detection results of the rotation sensor 70 and the pressure sensor 71 so as to exhibit the braking amount according to the detection result of the operation amount sensor 72. And a controller 80 for controlling the actuator 40 of the driving apparatus 100.

  The rotation sensor 70 is attached to the wheel 1 and detects the rotation speed of the wheel 1. The detection result of the rotation sensor 70 is transmitted to the controller 80. By detecting the rotation speed of the wheel 1 by the rotation sensor 70, it is possible to detect a malfunction such as the wheel 1 being locked.

  The pressure sensor 71 is attached to the housing 20 of the brake driving device 100 and detects the pressure in the first fluid pressure chamber 25. The detection result of the pressure sensor 71 is transmitted to the controller 80.

  The operation amount sensor 72 is provided on the brake pedal 2 operated by the operator, and detects the operation amount of the brake pedal 2. The detection result of the operation amount sensor 72 is transmitted to the controller 80.

  The controller 80 controls the rotation of the electric motor 41 so as to exhibit a desired braking force according to the amount of operation of the brake pedal 2 by the operator.

  Next, the operation of the brake system 101 and the brake drive device 100 will be described.

  In the following, the moving direction (right direction in FIG. 1) of the drive piston 30 that contracts the first fluid pressure chamber 25 is the “braking direction”, and the moving direction of the drive piston 30 that expands the first fluid pressure chamber 25 (in FIG. 1). (Left direction) is referred to as “release direction”. The rotation direction of the electric motor 41 that moves the drive piston 30 in the braking direction is referred to as “forward direction”, and the rotation direction of the electric motor 41 that moves the drive piston 30 in the release direction is referred to as “reverse direction”.

  In the non-braking state in which the operation amount of the brake pedal 2 is zero, the ball nut 44 contacts the stepped portion 24 of the cylinder 21 as shown in FIG. In this state, the brake actuator 11 of the brake device 10 is in the most contracted state, and the brake piston 14 is separated from the non-rotating disk 13 with a predetermined gap.

  When the brake pedal 2 is depressed by the operator from the non-braking state, the controller 80 instructs the electric motor 41 to rotate in the positive direction according to the operation amount of the brake pedal 2 detected by the operation amount sensor 72. Is output.

  As the electric motor 41 rotates in the forward direction, the ball screw 43 also rotates, and the drive piston 30 moves linearly in the braking direction against the urging force of the return spring 50 as shown in FIG. As a result, the hydraulic oil is discharged from the first fluid pressure chamber 25. Since the check valve 52 is provided in the connection passage 62, the hydraulic oil discharged from the first fluid pressure chamber 25 is not guided to the second passage 61 through the connection passage 62. Therefore, the hydraulic oil discharged from the first fluid pressure chamber 25 is supplied to the pressure chamber of the brake actuator 11 through the first port 25A, the first passage 60, the supply / discharge port 20A, and the hydraulic piping 16. Therefore, the braking actuator 11 is extended.

  When the brake actuator 11 is extended, the brake piston 14 is pressed toward the non-rotating disk 13. When the brake piston 14 is pressed against the non-rotating disk 13, the non-rotating disk 13 and the rotating disk 12 come into contact with each other. Thereby, a braking force (frictional force) corresponding to the pressing force of the braking piston 14 against the non-rotating disk 13 and the rotational speed of the wheel 1 is generated.

  The braking force by the brake device 10 is controlled by adjusting the pressing force of the braking piston 14 against the non-rotating disc 13. Specifically, an appropriate pressing force for exerting a desired braking force is calculated by the controller 80 with respect to the rotation speed of the wheel 1 detected by the rotation sensor 70. The pressing force by the brake device 10 is determined by the pressure of the hydraulic oil supplied to the brake actuator 11, that is, the pressure of the hydraulic oil discharged from the first fluid pressure chamber 25. Therefore, the controller 80 outputs a command signal to drive the electric motor 41 so that the pressure in the first fluid pressure chamber 25 detected by the pressure sensor 71 becomes a pressure that exerts a desired pressing force. As a result, the brake piston 14 is pressed against the non-rotating disk 13 with an appropriate pressing force with respect to the rotational speed of the wheel 1. In this way, a desired braking force corresponding to the amount of operation of the brake pedal 2 by the operator is exhibited by the brake device 10.

  As the drive piston 30 moves in the braking direction, the second fluid pressure chamber 26 expands. When the second fluid pressure chamber 26 is enlarged, hydraulic oil is supplied from the accumulator 51 to the second fluid pressure chamber 26 through the second passage 61 and the second port 26A. Thus, even if the second fluid pressure chamber 26 expands with the movement of the drive piston 30 in the braking direction, the hydraulic fluid is supplied from the accumulator 51 to the second fluid pressure chamber 26. There is no resistance to movement.

  When the amount of operation of the brake pedal 2 by the operator decreases, the controller 80 outputs a command signal to the electric motor 41 so as to rotate in the reverse direction.

  With the rotation of the electric motor 41 in the reverse direction, the ball screw 43 also rotates, and the drive piston 30 moves in the release direction. With the expansion of the first fluid pressure chamber 25, the hydraulic oil is discharged from the pressure chamber of the brake actuator 11 and supplied to the first fluid pressure chamber 25. Therefore, the braking actuator 11 is contracted.

  When the brake actuator 11 is contracted by a predetermined stroke, the brake piston 14 and the non-rotating disk 13 are separated from each other, and the braking of the brake device 10 is released. When the amount of operation of the brake pedal 2 by the operator becomes zero, as shown in FIG. 1, the ball nut 44 abuts on the stepped portion 24 and further movement of the drive piston 30 in the release direction is restricted. At this time, the brake actuator 11 is in the most contracted state. As a result, the brake piston 14 is separated from the non-rotating disk 13 so as to leave a predetermined gap.

  As the drive piston 30 moves in the release direction, the second fluid pressure chamber 26 contracts and hydraulic oil is discharged from the second fluid pressure chamber 26. The hydraulic oil discharged from the second fluid pressure chamber 26 is stored in the accumulator 51.

  As described above, the brake drive device 100 distributes the hydraulic oil between the first fluid pressure chamber 25 and the pressure chamber of the brake actuator 11 in the brake device 10 with the movement of the drive piston 30. Is driven to brake and release. The brake system 101 generates a desired braking force by the brake device 10 by driving the brake drive device 100 according to the amount of operation of the brake pedal 2 by the operator.

  Here, in the case where the second fluid pressure chamber is an air chamber in which gas is sealed, when the drive piston is moved in the braking direction, the volume of the second fluid pressure chamber increases and the pressure decreases. Such a pressure drop becomes a resistance of movement of the drive piston when braking the wheel by the brake device, and energy loss occurs in driving the brake device.

  In order to move the drive piston in the release direction and release the braking by the brake device, the second fluid pressure chamber must be contracted to compress the gas inside. When the hydraulic oil enters the second fluid pressure chamber and the volume occupied by the air chamber decreases, the gas must be compressed accordingly, and resistance is generated even when the drive piston is moved in the release direction. If the amount of hydraulic oil entering the second fluid pressure chamber is large, the amount of gas compression required to release braking of the brake device increases, and the drive piston cannot be moved sufficiently. There is also a possibility that 10 cannot be completely canceled.

  In order to prevent such a problem, it is conceivable to form a hole that opens in the surface of the housing and communicates with the second fluid pressure chamber 26 to release the second fluid pressure chamber 26 to the atmosphere. However, in this case, when the hydraulic oil in the first fluid pressure chamber enters the second fluid pressure chamber, the hydraulic oil may leak to the outside of the housing through the hole.

  On the other hand, the hydraulic fluid is supplied to and discharged from the first fluid pressure chamber 25 and the second fluid pressure chamber 26 of the brake drive device 100 as the drive piston 30 moves. For this reason, even if the first fluid pressure chamber 25 and the second fluid pressure chamber 26 expand as the drive piston 30 moves, resistance to the movement of the drive piston 30 does not occur. Therefore, energy loss in the brake drive device 100 can be reduced.

  Moreover, since resistance due to gas does not occur when releasing the brake device 10, there is no possibility that the brake device 10 cannot be completely released due to resistance to compress the gas. Further, since there is no need to form a hole that opens on the surface of the housing 20, there is no possibility that the hydraulic oil leaks through the hole.

  In general, in the braking state as shown in FIG. 2, if a problem such as failure to supply electric power to the electric motor 41 occurs, there is a possibility that the braking of the wheel 1 cannot be released. If the state where the braking of the wheel 1 cannot be released continues, there is a risk of causing a tire burst.

  On the other hand, in the brake drive device 100, the drive piston 30 is urged in the release direction by the return spring 50. Accordingly, even when such a malfunction occurs, the braking of the brake device 10 can be released by moving the drive piston 30 in the release direction by the urging force of the return spring 50. Therefore, even if a problem that the electric motor 41 cannot be driven occurs, tire burst can be prevented.

  Further, since the ball screw mechanism 42 has a small resistance to move the ball screw 43 and the ball nut 44 relative to each other, the ball nut 44 can be moved in the axial direction even if the biasing force of the return spring 50 is relatively small. Therefore, when the actuator 40 has the ball screw mechanism 42, a small return spring 50 having a small urging force can be used.

  Next, a modification of this embodiment will be described.

  In the above embodiment, the brake system is the brake system 101 that brakes the wheel 1 of the fixed-wing aircraft. Alternatively, the brake system may brake an automobile or a railroad wheel. Further, the brake system may brake a rotor of a helicopter (rotary wing aircraft) as a rotating body.

  In the above embodiment, the brake drive device 100 drives the brake device 10. The brake driving device 100 is not limited to driving the brake device 10 and may be used as a clutch driving device that drives a friction plate of a friction clutch mechanism.

  In the above embodiment, at least a part of the second port 26 </ b> A opens into the second cylinder part 23. Thereby, even immediately before the drive piston 30 contacts the stepped portion 24, the opening area of the second port 26A can be secured and the hydraulic oil can be smoothly discharged from the second fluid pressure chamber 26. Instead of this, the second port 26 </ b> A may not open to the second cylinder part 23. In this case, in order to smoothly discharge the hydraulic oil from the second fluid pressure chamber 26, a notch or the like is formed in the ball nut 44 or the drive piston 30, and the drive piston 30 is in contact with the step portion 24. Even if it exists, it is desirable for the 2nd port 26A and the 2nd cylinder part 23 to communicate through a notch etc.

  In the above embodiment, the actuator 40 includes the electric motor 41 and the ball screw mechanism 42. Alternatively, the actuator may have other configurations as long as the drive piston 30 is linearly moved. For example, the actuator 40 may be a voice coil motor, a linear actuator, a piezoelectric actuator, or the like.

  In the above embodiment, the brake drive device 100 includes the check valve 52 provided in the connection passage 62 and the relief valve 53 provided in the relief passage 63. The hydraulic fluid in the first fluid pressure chamber 25 and the first passage 60 is prevented by oil leakage or the like while preventing the hydraulic fluid from being guided from the first passage 60 to the second passage 61 by the connection passage 62 and the check valve 52. Is insufficient, the hydraulic fluid can be replenished from the accumulator 51 through the connection passage 62. The relief valve 53 is opened when the pressure in the first fluid pressure chamber 25, the first passage 60, and the hydraulic pipe 16 is abnormally increased, and the abnormal pressure can be released. Therefore, although it is desirable for the brake drive device 100 to include the connection passage 62, the check valve 52, the relief passage 63, and the relief valve 53, these may not be provided.

  According to the above embodiment, there exist the following effects.

  In the brake driving device 100, hydraulic fluid is supplied to the second fluid pressure chamber 26 as the hydraulic fluid is discharged from the first fluid pressure chamber 25. As described above, the hydraulic oil is supplied in accordance with the expansion of the second fluid pressure chamber 26, so that the pressure drop in the second fluid pressure chamber is prevented and the movement of the drive piston 30 is not hindered. Therefore, the energy loss of the brake drive device 100 can be reduced.

  Further, in the brake driving device 100, since the gas is not sealed in the first fluid pressure chamber 25 and the second fluid pressure chamber 26, there is no possibility that the brake device 10 cannot be completely released by the resistance to compress the gas. . Further, since it is not necessary to form a hole that opens in the surface of the housing 20 in order to eliminate resistance due to gas, there is no possibility that hydraulic oil leaks through the hole.

  In the brake driving device 100, the drive piston 30 is moved by the urging force of the return spring 50 even when the electric motor 41 of the actuator 40 cannot be driven. Therefore, even when a malfunction occurs, braking of the wheel 1 by the brake device 10 can be released, and a tire burst is prevented.

  Hereinafter, the configuration, operation, and effect of the embodiment of the present invention will be described together.

  A brake drive device 100 that drives a brake device 10 that brakes the wheel 1 includes a cylinder 21, a drive piston 30 that partitions the inside of the cylinder 21 into a first fluid pressure chamber 25 and a second fluid pressure chamber 26, and a drive piston 30. An actuator 40 that linearly moves along the inner peripheral surface of the first cylinder portion 22, and hydraulic oil is supplied to and discharged from the first fluid pressure chamber 25 and the second fluid pressure chamber 26 as the drive piston 30 moves. As the drive piston 30 moves, hydraulic oil is circulated between the first fluid pressure chamber 25 and the brake device 10 to drive the brake device 10.

  In this configuration, hydraulic fluid is supplied to the second fluid pressure chamber 26 as the hydraulic fluid is discharged from the first fluid pressure chamber 25. As described above, the hydraulic oil is supplied in accordance with the expansion of the second fluid pressure chamber 26, so that the pressure drop in the second fluid pressure chamber is prevented and the movement of the drive piston 30 is not hindered. Therefore, the energy loss of the brake drive device 100 that drives the brake device 10 is reduced.

  The brake drive device 100 further includes a return spring 50 that biases the drive piston 30 in a direction in which braking of the wheel 1 by the brake device 10 is released.

  In this configuration, even when the actuator 40 cannot be driven, the drive piston 30 is moved by the urging force of the return spring 50. Therefore, according to this configuration, the braking of the wheel 1 by the brake device 10 can be released even when there is a malfunction.

  In the brake drive device 100, the actuator 40 includes an electric motor 41 and a ball screw mechanism 42 that converts the rotation of the electric motor 41 into a linear motion of the drive piston 30.

  In this configuration, when the electric motor 41 rotates, the ball screw mechanism 42 causes the drive piston 30 to linearly move along the inner peripheral surface of the first cylinder portion 22.

  In addition, the brake drive device 100 includes an accumulator 51 that stores hydraulic oil, a first passage 60 that allows hydraulic oil to flow between the first fluid pressure chamber 25 and the brake device 10, a second fluid pressure chamber 26, and an accumulator 51. And a second passage 61 through which hydraulic fluid flows.

  In this configuration, the brake device 10 is driven by causing hydraulic oil to flow between the first fluid pressure chamber 25 and the brake device 10 through the first passage 60 as the drive piston 30 moves. As the driving piston 30 moves, the hydraulic fluid is supplied to and discharged from the accumulator 51 through the second passage 61 to the second fluid pressure chamber 26, so that even if the volume of the second fluid pressure chamber 26 increases, the pressure drop is prevented. The movement of the drive piston 30 is not hindered.

  Further, the brake driving device 100 allows only a connection passage 62 that connects the first passage 60 and the second passage 61 and a flow of hydraulic oil provided in the connection passage 62 toward the first passage 60 from the second passage 61. And a check valve 52.

  According to this configuration, even if the hydraulic oil in the first fluid pressure chamber 25 and the first passage 60 is insufficient, the hydraulic oil is replenished through the connection passage 62. Therefore, the first fluid pressure chamber 25 and the first passage 60 are used. It is possible to prevent the generation of negative pressure in the interior.

  The brake system 101 includes any one of the above-described configurations of the brake drive device 100, the brake device 10, a rotation sensor 70 that detects the rotational speed of the wheel 1, and a pressure sensor that detects the pressure in the first fluid pressure chamber 25. 71, an operation amount sensor 72 for detecting the operation amount of the brake pedal 2 by the operator, and the detection results of the rotation sensor 70 and the pressure sensor 71 so as to exert a braking force according to the detection result of the operation amount sensor 72. And a controller 80 for controlling the actuator of the brake driving device 100 based on the controller 80.

  In this configuration, the controller 80 controls the actuator 40 of the brake drive device 100 based on the detection results of the rotation sensor 70 and the pressure sensor 71, so that a desired braking force corresponding to the amount of braking operation by the operator is applied to the brake device 10. Can be demonstrated.

  The embodiment of the present invention has been described above. However, the above embodiment only shows a part of application examples of the present invention, and the technical scope of the present invention is limited to the specific configuration of the above embodiment. Absent.

  DESCRIPTION OF SYMBOLS 1 ... Wheel (rotary body) 10 ... Brake device, 11 ... Brake actuator, 21 ... Cylinder, 25 ... 1st fluid pressure chamber, 26 ... 2nd fluid pressure chamber, 30 ... Drive piston, 40 ... Actuator, 41 ... Electricity Motor, 42 ... Ball screw mechanism, 50 ... Return spring, 51 ... Accumulator (storage part), 52 ... Check valve, 60 ... First passage, 61 ... Second passage, 62 ... Connection passage, 70 ... Rotation sensor (Rotation) Detector), 71 ... pressure sensor (pressure detector), 72 ... operation amount sensor (operation amount detector), 80 ... controller, 100 ... brake drive device, 101 ... brake system

Claims (6)

A brake drive device for driving a brake device for braking a rotating body,
A cylinder,
A drive piston that divides the inside of the cylinder into a first fluid pressure chamber and a second fluid pressure chamber;
An actuator for linearly moving the drive piston along the inner peripheral surface of the cylinder,
Working fluid is supplied to and discharged from the first fluid pressure chamber and the second fluid pressure chamber as the drive piston moves.
A brake drive device that drives the brake device by causing a working fluid to flow between the first fluid pressure chamber and the brake device as the drive piston moves.   The brake drive device according to claim 1, further comprising a return spring that biases the drive piston in a direction in which braking of the rotating body by the brake device is released. The actuator is
An electric motor;
The brake drive device according to claim 1, further comprising: a ball screw mechanism that converts rotation of the electric motor into linear motion of the drive piston. A reservoir for storing the working fluid;
A first passage for flowing a working fluid between the first fluid pressure chamber and the brake device;
4. The brake drive device according to claim 1, further comprising a second passage through which a working fluid is circulated between the second fluid pressure chamber and the storage portion. 5. A connection passage connecting the first passage and the second passage;
The brake drive device according to claim 4, further comprising: a check valve provided in the connection passage and allowing only a flow of the working fluid from the second passage toward the first passage. The brake drive device according to any one of claims 1 to 5,
The brake device;
A rotation detector for detecting a rotation speed of the rotating body;
A pressure detector for detecting the pressure of the first fluid pressure chamber;
An operation amount detector for detecting the operation amount of the operation unit by the operator;
A controller for controlling the actuator of the brake driving device based on the detection results of the rotation detector and the pressure detector so as to exert a braking force according to the detection result of the operation amount detector. Brake system characterized by

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