JP6219356B2 - Electric brake device - Google Patents

Description

  The present invention relates to an electric brake device including a parking lock mechanism, and to a technique for preventing the electric brake device from freezing without releasing a braking force.

Normally, when a vehicle is parked, the vehicle is prevented from moving by using a parking brake that is mechanically independent from a so-called foot brake (also called a service brake). However, in winter and cold regions, the parking brake may freeze and cannot be released. Therefore, in a cold district or the like, the parking brake is not used when the vehicle is parked. For example, the automatic transmission is set to the parking range, and the locking portion in the automatic transmission is locked to the locked portion. It has been proposed to prevent the movement of the camera simply.
For example, in cold districts and the like, in order to prevent the electric parking brake from freezing while the vehicle is parked, a technique for releasing the electric parking brake when a sensor that detects the outside air temperature of the vehicle reaches a freezing temperature has been proposed (patent) Reference 1).

JP 2005-082035 A

  In the above conventional technique, the electric parking brake is released and the vehicle is prohibited from moving by the parking lock mechanism of the automatic transmission. However, the parking lock mechanism using the automatic transmission is an auxiliary mechanism, such as a slope. Then, a load is applied to the automatic transmission. If an excessive load is applied to the automatic transmission and a problem occurs in the locked state between the locking portion and the locked portion in the automatic transmission, the vehicle may move undesirably.

  An object of the present invention is to provide an electric brake device that can reliably prevent freezing with a simple configuration without releasing a braking force during parking.

An electric brake device according to a first aspect of the present invention includes an electric motor, a braking force load mechanism that applies a braking force to a wheel by the output of the electric motor, and a braking force slackening operation of the braking force load mechanism is inhibited. A lock mechanism that can be switched between a locked state and an allowed unlocked state, and the lock mechanism biases the lock member to an unlocked state and a lock member that can be switched between a locked state and an unlocked state. An electric brake device having an urging means and a drive source for switching and driving the lock member to a locked state against the urging force of the urging means, and detects an outside air temperature of the vehicle or an electric brake device temperature When the temperature sensor is provided, the braking force load mechanism applies a braking force, and the lock mechanism is in a locked state, the temperature sensor is Upon detecting the temperature T1 of freezing immediately before the constant has been electrically powered brake system, antifreezing energizing means is provided, the antifreeze energizing means for controlling to start energizing the drive source, thereby energizing the drive source Thus, when the temperature detected by the temperature sensor becomes higher than the set temperature T2 set higher than the temperature T1, the power supply to the drive source is cut off.

  According to this configuration, during running, the locking member of the locking mechanism is unlocked by the urging force of the urging means, and the braking force load mechanism applies a braking force to the wheels by driving the electric motor. To do. At the time of parking, in a state where the braking force load mechanism applies a braking force to the wheels, the lock member is driven to be switched to the locked state by the drive source against the urging force by the urging means. After that, for example, when the driver leaves the vehicle, the ignition of the vehicle is turned off, and even if the power supply to the drive source is lost, the lock member engages with the other member and the frictional force with the other member. Therefore, the locked state is not released. Thereby, the movement of the vehicle is prohibited. By setting the lock mechanism to the locked state, the braking force is maintained even when the electric motor is stopped. At the time of parking, for example, if the urging means of the lock mechanism is frozen, the lock member cannot be returned to the unlocked state only by the urging force of the urging means. That is, the locked state cannot be released.

However, when the vehicle is parked, the temperature sensor detects the outside air temperature of the vehicle or the temperature of the electric brake device. When the braking force load mechanism applies a braking force and the lock mechanism is in the locked state, if the temperature sensor detects the set temperature immediately before freezing of the electric brake device, the anti-freeze energizing means drives the lock mechanism. Control the source to start energization. For example, a linear solenoid is used as the drive source. By energizing the linear solenoid, the drive source itself generates heat using the coil as a heat source, thereby raising the temperature of the electric brake device. As a result, freezing of the lock mechanism of the electric brake device and the like can be reliably prevented during parking, and unlocking can be normally performed as necessary, such as when the vehicle starts. Therefore, the vehicle can be started without delay. Since the drive source of the lock mechanism is used as a heat source in this way, a heat source dedicated to freezing prevention is unnecessary, and freezing prevention can be performed with a simple configuration. When the lock mechanism is operated in the locked state, the lock member is already held in the locked state by the frictional force with other members. Therefore, even if the drive source is energized, the locked state is not desired. Will not be released.
An electric brake device according to a second aspect of the present invention includes an electric motor, a braking force load mechanism that applies a braking force to the wheels by the output of the electric motor, and a braking force slackening operation of the braking force load mechanism is inhibited. A lock mechanism that can be switched between a locked state and an allowed unlocked state, and the lock mechanism biases the lock member to an unlocked state and a lock member that can be switched between a locked state and an unlocked state. An electric brake device having urging means and a drive source for switching and driving the lock member to a locked state against the urging force of the urging means,
A temperature sensor for detecting the outside air temperature of the vehicle or the temperature of the electric brake device is provided,
When the braking force loading mechanism applies a braking force and the locking mechanism is in the locked state, the temperature sensor detects the temperature T1 immediately before freezing of the set electric brake device, and the drive source is energized. Anti-freezing energizing means for controlling to start is provided,
The antifreeze energizing means, by energizing the driving source, the temperature detected by the temperature sensor, when it is detected that set high set point temperature T _H than the temperature T1, to the drive source The current to be energized is controlled to be smaller than the original current.

  The anti-freezing energizing means may repeatedly energize and shut off the drive source at regular intervals while the temperature sensor detects the set temperature. After the energization of the drive source of the lock mechanism is started, the temperature detected by the temperature sensor tends to increase with time, for example. By continuously energizing the drive source after that, it is possible to reliably prevent the electric brake device from freezing without causing a temperature decrease tendency. In this case, however, a load is applied to the battery. Further, when the drive source is energized for a relatively long time and the drive source itself is at a high temperature, the temperature tends not to decrease even if the energization to the drive source is temporarily interrupted.

Therefore, the freeze prevention energizing means repeatedly energizes and interrupts the drive source at regular intervals, thereby reducing the load on the battery and freezing the electric brake device as compared with the case of continuously energizing the drive source. Can be prevented. Although it is conceivable to continuously energize the drive source and reduce the current supplied to the drive source when the temperature rises to a predetermined temperature, when the vehicle is parked for a long time, for example, there is a difference in temperature between day and night. When the current is large, it is possible to reduce the load on the battery and to control it more easily by repeatedly energizing and interrupting the drive source at regular intervals than when performing current control while energizing continuously.
A reduction mechanism that decelerates the rotation of the electric motor may be provided, and the braking force load mechanism may convert a rotational motion output from the reduction mechanism into a linear motion and apply a braking force to the wheels.

  The electric brake device of the reference proposal example includes an electric motor, a braking force load mechanism that applies a braking force to the wheels by the output of the electric motor, and a locked state that prevents a braking force slack operation of the braking force load mechanism. A lock mechanism that can be switched over between an unlocked state and an unlocked state, wherein the lock mechanism can be switched between a locked state and an unlocked state; And an electric brake device having a drive source for switching the lock member to a locked state against the urging force of the urging means and provided with a temperature sensor for detecting the outside air temperature of the vehicle or the temperature of the electric brake device. When the braking force load mechanism applies a braking force and the lock mechanism is in the locked state, the temperature sensor freezes the set electric brake device. When the previous temperature is detected, anti-freezing energizing means is provided for controlling the drive source to start energization, and has a start operation detecting means for detecting a detection signal indicating the start operation of the vehicle, and the anti-freeze energizing means Is a detection signal indicating the start operation of the vehicle by the start operation detecting means when the braking force load mechanism applies the braking force and the lock mechanism is in the locked state and the temperature sensor detects the set temperature. When detected, the drive source is energized. Prevention of freezing of the electric brake at the time of parking is performed by energizing the drive source by temperature detection. However, if the set temperature for energization is too high, the power consumption of the battery increases. In order to reduce power consumption, freezing may occur when the set temperature is lowered. Even if such a slight freezing occurs, if the detection signal indicating the start operation of the vehicle is detected and the drive source is energized as described above, the freezing of the electric brake device can be eliminated at an early stage. The vehicle can be started without delay.

The start operation detecting means may use a vehicle door “open” as a detection signal.
The start operation detecting means may use a detection signal indicating vehicle door lock release.
The start operation detecting means may use a vehicle ignition signal “ON” as a detection signal.
The start operation detecting means may include a sensor that detects that the driver is seated on the driver's seat side seat of the vehicle.
The start operation detecting means may use a pedal operation for applying a braking force to the wheel as a detection signal.
The start operation detecting means may use a signal for remotely starting the engine as a detection signal.

An electric brake device according to another reference proposal includes an electric motor, a braking force load mechanism that applies a braking force to a wheel by an output of the electric motor, and a lock that prevents a braking force slack operation of the braking force load mechanism. A lock mechanism that can be switched between a locked state and an allowed unlocked state, the lock mechanism switching between a locked state and an unlocked state, and switching the lock member between a locked state and an unlocked state An electric brake device having a double-acting drive source for driving, provided with a temperature sensor for detecting an outside air temperature of the vehicle or a temperature of the electric brake device, the braking force load mechanism loading the braking force, and When the lock mechanism is in the locked state, if the temperature sensor detects the set temperature immediately before freezing of the electric brake device, the lock member maintains the locked state. As to, characterized in that a freezing preventing energization means for controlling to start energizing the double-acting driving source of the locking mechanism.
According to this configuration, when the vehicle is parked, when the braking force load mechanism applies a braking force and the lock mechanism is in the locked state, the anti-freezing energizing means is locked when the temperature sensor detects the temperature immediately before freezing. Control is performed to start energization of the double-acting drive source so that the member maintains the locked state. Accordingly, the temperature of the electric brake device is increased by the heat generated by the drive source itself. As a result, freezing of the lock mechanism of the electric brake device and the like can be reliably prevented during parking, and unlocking can be normally performed as necessary, such as when the vehicle starts. Therefore, the vehicle can be started without delay.
An automobile according to the present invention includes any one of the electric brake devices.

An electric brake device according to a first aspect of the present invention includes an electric motor, a braking force load mechanism that applies a braking force to a wheel by the output of the electric motor, and a braking force slackening operation of the braking force load mechanism is inhibited. A lock mechanism that can be switched between a locked state and an allowed unlocked state, and the lock mechanism biases the lock member to an unlocked state and a lock member that can be switched between a locked state and an unlocked state. An electric brake device having an urging means and a drive source for switching and driving the lock member to a locked state against the urging force of the urging means, and detects an outside air temperature of the vehicle or an electric brake device temperature When the temperature sensor is provided, the braking force load mechanism applies a braking force, and the lock mechanism is in a locked state, the temperature sensor is Upon detecting the temperature T1 of freezing immediately before the constant has been electrically powered brake system, antifreezing energizing means is provided, the antifreeze energizing means for controlling to start energizing the drive source, thereby energizing the drive source When the temperature detected by the temperature sensor becomes higher than the set temperature T2 set higher than the temperature T1, the power supply to the drive source is cut off. For this reason, at the time of parking, freezing can be reliably prevented with a simple configuration without releasing the braking force, and normal running can be started.
An electric brake device according to a second aspect of the present invention includes an electric motor, a braking force load mechanism that applies a braking force to the wheels by the output of the electric motor, and a braking force slackening operation of the braking force load mechanism is inhibited. A lock mechanism that can be switched between a locked state and an allowed unlocked state, and the lock mechanism biases the lock member to an unlocked state and a lock member that can be switched between a locked state and an unlocked state. An electric brake device having an urging means and a drive source for switching and driving the lock member to a locked state against the urging force of the urging means, and detects an outside air temperature of the vehicle or an electric brake device temperature temperature sensor is provided, the antifreeze energizing means, by energizing the driving source, the temperature detected by the temperature sensor, the temperature Once it is detected that set high set point temperature T _H than T1, control smaller than the original current current applied to the driving source. For this reason, at the time of parking, freezing can be reliably prevented with a simple configuration without releasing the braking force, and normal running can be started.

  The electric brake device of the reference proposal example includes an electric motor, a braking force load mechanism that applies a braking force to the wheels by the output of the electric motor, and a locked state that prevents a braking force slack operation of the braking force load mechanism. A lock mechanism that can be switched over between an unlocked state and a lock state, and a lock member that can be switched between a locked state and an unlocked state, and driving the lock member to switch between a locked state and an unlocked state. An electric brake device having a double-acting drive source, provided with a temperature sensor for detecting the outside air temperature of the vehicle or the temperature of the electric brake device, wherein the braking force load mechanism loads the braking force, and the lock mechanism When the temperature sensor detects the set temperature just before freezing of the electric brake device, the lock member maintains the locked state. As is provided with the antifreeze energizing means for controlling to start energizing the drive source of the double-acting of the locking mechanism. For this reason, at the time of parking, freezing can be reliably prevented with a simple configuration without releasing the braking force, and normal running can be started.

It is sectional drawing of the electric brake device which concerns on 1st Embodiment of this invention. It is an expanded sectional view of the deceleration mechanism of the same electric brake device. It is an expanded sectional view of the lock mechanism of the electric brake device. (A) is a diagram schematically showing a lock mechanism in a locked state, and (B) is a diagram schematically showing a lock mechanism in an unlocked state. It is a block diagram of a control system of the electric brake device. It is a figure showing the relationship between the preset temperature by a temperature sensor and time in the electric brake device. It is a figure showing the relationship between the preset temperature by a temperature sensor, and time in the electric brake device which concerns on other embodiment of this invention. It is a figure showing the relationship between the preset temperature by a temperature sensor, and time in the electric brake device which concerns on further another embodiment of this invention. It is a block diagram of the control system of the electric brake device which concerns on a reference proposal example. It is the schematic of the lock mechanism of the electric brake device which concerns on another reference proposal example. (A) is the schematic which made the lock mechanism of the electric brake device which concerns on another reference proposal example into the locked state, (B) is the schematic which made the lock mechanism the unlocked state.

A first embodiment of the present invention will be described with reference to FIGS. The electric brake device according to this embodiment serves as both a service brake used when the vehicle is driven and a parking brake used when the vehicle is stopped. The electric brake device can be used as a service brake by setting a lock mechanism described later to an unlocked state, and the electric brake device can be used as a parking brake by setting the lock mechanism to a locked state.
As shown in FIG. 1, the electric brake device includes a housing 1, an electric motor 2, a speed reduction mechanism 3 that decelerates rotation of the electric motor 2, a braking force load mechanism 4, a lock mechanism 5, a temperature sensor. 6 (FIG. 5) and anti-freezing energizing means 7 (FIG. 5). A base plate 8 extending radially outward is provided at the open end of the housing 1, and the electric motor 2 is supported on the base plate 8. In the housing 1, a braking force load mechanism 4 that loads a braking force to the wheels, in this example, the brake disk 9, is incorporated by the output of the electric motor 2. The opening end of the housing 1 and the outer surface of the base plate 8 are covered with a cover 10.

The braking force load mechanism 4 will be described.
The braking force load mechanism 4 is a so-called linear motion mechanism that loads the braking force on the wheels by converting the rotational motion output from the speed reduction mechanism 3 into a linear motion. The braking force load mechanism 4 includes a slide member 11, a bearing member 12, an annular thrust plate 13, a thrust bearing 14, rolling bearings 15 and 15, a rotating shaft 16, a carrier 17, a sliding bearing 18, 19. A cylindrical slide member 11 is supported on the inner peripheral surface of the housing 1 so as to be prevented from rotating and movable in the axial direction. On the inner peripheral surface of the slide member 11, a spiral protrusion 11 a that protrudes a predetermined distance radially inward and is formed in a spiral shape is provided. A plurality of planetary rollers, which will be described later, mesh with the spiral protrusion 11a.

  A bearing member 12 is provided on one end side in the axial direction of the slide member 11 in the housing 1. The bearing member 12 has a flange portion extending radially outward and a boss portion. Rolling bearings 15 and 15 are fitted into the boss portions, and a rotary shaft 16 is fitted to the inner ring inner surface of each of the bearings 15 and 15. Therefore, the rotating shaft 16 is rotatably supported by the bearing member 12 via the bearings 15 and 15.

  A carrier 17 is provided on the inner periphery of the slide member 11 so as to be rotatable about the rotary shaft 16. The carrier 17 includes disks 17a and 17b that are arranged to face each other in the axial direction. The disk 17b close to the bearing member 12 may be referred to as an inner disk 17b, and the disk 17a may be referred to as an outer disk 17a. Of the one disk 17a, a side surface facing the other disk 17b is provided with an interval adjusting member 17c protruding in the axial direction from the outer peripheral edge portion on this side surface. In order to adjust the interval between the plurality of planetary rollers 20, a plurality of the interval adjusting members 17 c are arranged at intervals in the circumferential direction. The discs 17a and 17b are integrally provided by the distance adjusting member 17c.

  The inner disk 17b is supported by a slide bearing 18 fitted between the inner shaft 17b and the inner shaft 17b so as to be rotatable and movable in the axial direction. A shaft insertion hole is formed at the center of the outer disk 17a, and a slide bearing 19 is fitted in the shaft insertion hole. The outer disk 17a is rotatably supported on the rotary shaft 16 by a slide bearing 19. A washer that receives a thrust load is fitted to the end of the rotating shaft 16, and a retaining ring for preventing the washer from coming off is provided.

  The carrier 17 is provided with a plurality of roller shafts 21 at intervals in the circumferential direction. Both end portions of each roller shaft 21 are supported across the disks 17a and 17b. That is, the discs 17a and 17b are formed with a plurality of shaft insertion holes each having a long hole, and both end portions of the roller shafts 21 are inserted into the shaft insertion holes, and the roller shafts 21 are supported so as to be movable in the radial direction. The An elastic ring 22 that urges the roller shafts 21 radially inward is stretched around the plurality of roller shafts 21.

A planetary roller 20 is rotatably supported on each roller shaft 21, and each planetary roller 20 is interposed between the outer peripheral surface of the rotary shaft 16 and the inner peripheral surface of the slide member 11. Each planetary roller 20 is pressed against the outer peripheral surface of the rotating shaft 16 by the urging force of the elastic ring 22 spanned across the plurality of roller shafts 21. As the rotating shaft 16 rotates, each planetary roller 20 that contacts the outer peripheral surface of the rotating shaft 16 rotates due to contact friction. On the outer peripheral surface of the planetary roller 20, a spiral groove that meshes with the spiral protrusion 11a of the slide member 11 is formed.
A washer and a thrust bearing (both not shown) are interposed between the inner disk 17b of the carrier 17 and one axial end of the planetary roller 20. In the housing 1, an annular thrust plate 13 and a thrust bearing 14 are provided between the inner disk 17 b and the bearing member 12.

The deceleration mechanism 3 will be described.
As shown in FIG. 2, the speed reduction mechanism 3 is a mechanism that transmits the rotation of the electric motor 2 at a reduced speed to the output gear 23 fixed to the rotation shaft 16, and includes a plurality of gear trains. In this example, the speed reduction mechanism 3 is fixed to the end of the rotary shaft 16 by sequentially reducing the rotation of the input gear 24 attached to the rotor shaft 2 a of the electric motor 2 by the gear trains 25, 26 and 27. Transmission to the output gear 23 is possible.

The lock mechanism 5 will be described.
As shown in FIG. 3, the lock mechanism 5 is configured to be switchable between a locked state where the braking force slack operation of the braking force load mechanism 4 (FIG. 2) is blocked and an allowed unlocked state. In the round frame A of FIG. 3, the locked state of the locking mechanism 5 is represented by a two-dot chain line, and the unlocked state is represented by a solid line. The deceleration mechanism 3 is provided with a lock mechanism 5. As shown in FIG. 4A, the lock mechanism 5 is a casing 40, a lock pin 29 that is a lock member, a biasing means 41 that biases the lock pin 29 to an unlocked state, and a drive source. And a linear solenoid 30. The casing 40 is supported by the base plate 8 (FIG. 3), and a pin hole that allows the lock pin 29 to advance and retreat is formed in the base plate 8.

  A linear solenoid 30 including a coil bobbin 42 and a coil 43 wound around the coil bobbin 42 is provided in the casing 40. A part of the lock pin 29 made of an iron core is slidably provided in the hole of the coil bobbin 42. In the casing 40, a flange-shaped spring receiving member 44 is fixed to the middle portion in the longitudinal direction of the lock pin 29. In the casing 40, a base end portion 40a in which a through hole allowing the lock pin 29 to advance and retract is formed. In the casing 40, an urging means 41 including a compression coil spring is interposed between the base end portion 40a and the spring receiving member 44.

The lock pin 29 can be switched between a locked state shown in FIG. 4 (A) and an unlocked state shown in FIG. 4 (B). That is, as shown in FIG. 3, the intermediate gear 28 on the output side of the gear train 26 has a plurality of locking holes 28a formed at regular intervals in the circumferential direction. A lock pin 29 is provided at one point on the pitch circle of the locking holes 28a so as to be advanced and retracted by a linear solenoid 30 which is a pin driving actuator. When the linear solenoid 30 is energized when the lock pin 29 is in the unlocked state shown in FIG. 4B, the linear solenoid 30 resists the urging force by the urging means 41 as shown in FIG. Then, the lock pin 29 is switched to the locked state and driven.
The lock mechanism 29 is locked by advancing the lock pin 29 by the linear solenoid 30 to engage the locking hole 28a and prohibiting the rotation of the intermediate gear 28. When the linear solenoid 30 is turned off, the spring receiving member 44 is pushed down to the bottom side in the casing 40 by the urging force of the urging means 41. As a result, the lock pin 29 is retracted into the casing 40 to be detached from the locking hole 28a, and the rotation of the intermediate gear 28 is allowed, whereby the lock mechanism 5 can be unlocked.

The temperature sensor 6 and the freeze prevention energizing means 7 will be described.
As shown in FIG. 5, the vehicle is provided with an ECU 31 that is an electric control unit that controls the entire vehicle, and a temperature sensor 6 that detects the outside air temperature of the vehicle. A temperature sensor 6 is attached to, for example, a knuckle arm of the vehicle. The ECU 31 mainly includes a travel control unit 31a and a general control unit 31b. The traveling control unit 31 a issues an acceleration / deceleration command from an acceleration command output from the sensor 38 according to the depression amount of the accelerator pedal 37 and a deceleration command output from the sensor 33 according to the operation amount of the brake pedal 32. Generate. In this example, the temperature sensor 6 is provided on the knuckle arm of the vehicle main body, but is not limited to this form. When the space between the housing 1 and the speed reduction mechanism 3 is frozen, the temperature sensor 6 may be provided in the electric brake device, for example, the housing 1 or the casing 40 of the lock mechanism 5 to detect the temperature of the electric brake device. In these cases, the temperature immediately before freezing of the electric brake device can be detected more accurately.

The general control unit 31b has a function of controlling the brake control unit 31ba, the freeze prevention energizing means 7, and various auxiliary machine systems (not shown). The brake control unit 31ba is means for controlling the electric brake device as a parking brake when the vehicle is stopped. The brake control unit 31ba can drive the linear solenoid 30 via the drive circuit 35 based on the detection signal of the sensor 33 and the operation command of the lock mechanism operation unit 34.
An inverter device 39 is connected to the ECU 31, and the inverter device 39 includes a power circuit unit 39a provided for each electric motor 2 and a motor control unit 39b for controlling the power circuit unit 39a. The motor control part 39b may be provided in common with respect to each power circuit part 39a, or may be provided separately.

The motor control unit 39b includes a computer, a program executed on the computer, and an electronic circuit. This motor control part 39b converts into a current command according to the deceleration command given from the traveling control part 31a or the brake control part 31ba, and gives a current command to the PWM driver of the power circuit part 39a.
When the braking force load mechanism 4 applies a braking force and the lock mechanism 5 is in the locked state, the anti-freezing energization means 7 detects the set temperature immediately before freezing of the electric brake device. The linear solenoid 30 that is the drive source of the lock mechanism 5 is controlled to start energization. The set temperature immediately before freezing of the electric brake device can be arbitrarily determined based on a temperature of 0 ° C. When the temperature sensor 6 detects the outside air temperature, if the temperature in the housing 1 of the electric brake device is kept relatively higher than the outside air temperature, the temperature immediately before freezing of the electric brake device is determined as the temperature sensor. The temperature may be corrected to be lower than the outside air temperature detected in 6.

  As described above, the anti-freezing energizing means 7 has three conditions, that is, (1) the braking force load mechanism 4 applies the braking force, (2) the lock mechanism 5 is in the locked state, (3) the temperature sensor. When all of 6 is equal to or lower than the set temperature, the linear solenoid 30 is energized. The freeze prevention energization means 7 always detects the outside air temperature with the temperature sensor 6. When the temperature sensor 6 becomes higher than the set temperature by energizing the linear solenoid 30, the anti-freezing energizing means 7 interrupts energization to the linear solenoid 30. Here, even if the energization to the linear solenoid 30 is interrupted, the lock pin 29 is engaged with the engagement hole 28a and is held in the locked state by the frictional force with the engagement hole 28a. Will not be released. As shown in FIG. 6, the set temperatures are different between energization and shut-off, and an energization set temperature T1 and a shut-off set temperature T2 are set, respectively. The energization set temperature T1 and the shut-off set temperature T2 are both set higher than the temperature 0 ° C., and the shut-off set temperature T2 is set higher than the energization set temperature T1.

  According to the electric brake device described above, during traveling, the lock pin 29 of the lock mechanism 5 is unlocked by the urging force of the urging means 41, and the electric motor 2 is driven, whereby the braking force load mechanism. 4 applies a braking force to the wheels. At the time of parking, in a state where the braking force load mechanism 4 applies a braking force to the wheels, the lock pin 29 of the lock mechanism 5 is switched to the locked state by the linear solenoid 30 against the urging force by the urging means 41. To do. After that, for example, when the driver leaves the vehicle, the ignition of the vehicle is turned off, and even if the power supply to the linear solenoid 30 is lost, the lock pin 29 engages with the locking hole 28a and the locking hole 28a. Therefore, the locked state is not released. Thereby, the movement of the vehicle is prohibited. By setting the lock mechanism 5 to the locked state, the braking force is maintained even when the electric motor 2 is stopped. If, for example, the urging means 41 of the lock mechanism 5 is frozen during parking, the lock pin 29 cannot be returned to the unlocked state only by the urging force of the urging means 41. That is, the locked state cannot be released.

  However, when the vehicle is parked, the temperature sensor 6 detects the outside air temperature of the vehicle or the temperature of the electric brake device. When all the three conditions are satisfied when the vehicle is parked, the freeze prevention energization means 7 controls the linear solenoid 30 of the lock mechanism 5 to start energization. By energizing the linear solenoid 30, the linear solenoid 30 itself generates heat using the coil 43 of the linear solenoid 30 as a heat source, thereby increasing the temperature of the electric brake device. Thereby, at the time of parking, freezing of the lock mechanism 5 etc. of an electric brake device can be prevented reliably, and unlocking etc. can be performed normally. Therefore, the vehicle can be started without delay. Since the linear solenoid 30 of the lock mechanism 5 is used as a heat source in this way, a dedicated heat source for preventing freezing is unnecessary, and freezing can be prevented with a simple configuration. When the lock mechanism 5 is operated in the locked state, the lock pin 29 is already held in the locked state by the frictional force with any one of the locking holes 28a of the intermediate gear 28. Therefore, the linear solenoid 30 Even if current is supplied to the power supply, the locked state is not undesirably released.

As another embodiment, as shown in FIG. 7, when the linear solenoid 30 is energized at the energization set temperature T _< b> 1 when the vehicle is parked, it is detected that the set temperature TH is higher than the temperature T _< b> 1. Thus, the current supplied to the linear solenoid 30 may be controlled to be small. In this case, it is possible to reduce the load on the battery mounted on the vehicle, rather than continuing to energize the linear solenoid 30 with a constant current.
As shown in FIG. 8, the freeze prevention energizing means 7 may repeatedly energize and shut off the linear solenoid 30 at regular intervals (every time t1) while detecting the temperature. After the energization of the linear solenoid 30 is started, the temperature detected by the temperature sensor 6 tends to increase with time, for example. By continuously energizing the linear solenoid 30 thereafter, it is possible to reliably prevent the electric brake device from freezing without a tendency to decrease in temperature, but in this case, a load is applied to the battery. Further, when the linear solenoid 30 is energized for a relatively long time and the linear solenoid itself becomes high temperature, the temperature tends not to decrease even if the energization to the linear solenoid 30 is temporarily interrupted.

  Therefore, the freeze prevention energizing means 7 repeatedly performs energization and interruption to the linear solenoid 30 at regular intervals, thereby reducing the load on the battery and reducing the load on the battery as compared with the case of continuously energizing the linear solenoid 30. Can be prevented from freezing. In the case where the parking time of the vehicle is long, for example, when there is a large difference in temperature between day and night, it is more battery-powered to repeat energization and interruption of the linear solenoid 30 at regular intervals than when current control is performed while energizing continuously. Can be reduced and can be controlled easily.

As shown in FIG. 9, a start operation detecting means 36 for detecting a detection signal representing a start operation of the vehicle is provided, and the antifreezing energizing means 7 is provided with a braking force applied by the braking force load mechanism 4 and a lock mechanism 5. When the temperature sensor 6 detects the set temperature in the locked state, the linear solenoid 30 may be energized when the start operation detecting means 36 detects a detection signal indicating the start operation of the vehicle. .
The start operation detection means 36 can apply the following detection signals.
-The vehicle door "open" is used as a detection signal.
・ The vehicle door lock release is used as a detection signal.
-The vehicle's ignition "ON" is used as a detection signal.
A detection signal by a sensor that detects that the driver is seated on the driver's seat of the vehicle. A pedal operation that applies braking force to the wheel is used as a detection signal.
A signal for remotely starting the engine from a location away from the vehicle is used as a detection signal.
Even if a slight freezing has occurred, as described above, if the electric motor 2 is energized when a detection signal indicating the start operation of the vehicle is detected, the freezing of the electric brake device can be quickly eliminated, The vehicle can be started without delay.

Instead of the aforementioned locking mechanism 5, a locking mechanism 5A shown in FIG. 10 may be applied. The lock mechanism 5A includes a casing 40, a lock pin 29 that is a lock member, and double-acting linear solenoids 30A and 30B that switch and drive the lock pin 29 between a locked state and an unlocked state. When the linear solenoid 30A is energized and the linear solenoid 30B is de-energized, the lock pin 29 is switched to the locked state and driven. When the energization of the linear solenoid 30A is released and the linear solenoid 30B is energized, the lock pin 29 is switched to the unlocked state and driven.
Even in this configuration, the temperature of the electric brake device is raised by heating the linear solenoid 30A using the coil 43 of the linear solenoid 30A as a heat source during parking. Thereby, at the time of parking, freezing of the lock mechanism 5A of the electric brake device can be surely prevented, and unlocking can be normally performed.

  A lock mechanism 5B shown in FIGS. 11A and 11B may be applied. The lock mechanism 5B includes a casing 40, a lock pin 29 that is a lock member, a biasing means 41 that biases the lock pin 29 to the locked state of FIG. 11A, and a biasing force by the biasing means 41. It has a linear solenoid 30 that is a release drive source that releases the lock pin 29 to the unlocked state shown in FIG. An inner flange 45 is fixed in the casing 40, and an urging means 41 including a compression coil spring is interposed between the inner flange 45 and the spring receiving member 44 in the casing 40. Also in this case, the temperature of the electric brake device is raised by heating the linear solenoid 30 using the coil 43 of the linear solenoid 30 as a heat source during parking. Thereby, at the time of parking, freezing of the lock mechanism 5B of the electric brake device can be surely prevented, and unlocking can be normally performed.

DESCRIPTION OF SYMBOLS 2 ... Electric motor 3 ... Deceleration mechanism 4 ... Braking force load mechanism 5, 5A, 5B ... Lock mechanism 6 ... Temperature sensor 7 ... Anti-freezing energizing means 29 ... Lock pin 30, 30A, 30B ... Linear solenoid 36 ... Starting operation detection means

Claims (2)

Switchable between an electric motor, a braking force load mechanism that applies a braking force to the wheels by the output of the electric motor, and a locked state that prevents the braking force slack operation of the braking force load mechanism and an allowed unlocked state A locking member that can be switched between a locked state and an unlocked state, a biasing means that biases the lock member to the unlocked state, and a biasing force generated by the biasing means. An electric brake device having a drive source for switching the lock member to a locked state against the drive,
A temperature sensor for detecting the outside air temperature of the vehicle or the temperature of the electric brake device is provided,
When the braking force loading mechanism applies a braking force and the locking mechanism is in the locked state, the temperature sensor detects the temperature T1 immediately before freezing of the set electric brake device, and the drive source is energized. Anti-freezing energizing means for controlling to start is provided,
The anti-freezing energization means energizes the drive source when the temperature detected by the temperature sensor becomes higher than a set temperature T2 set higher than the temperature T1 by energizing the drive source. An electric brake device characterized by being cut off. Switchable between an electric motor, a braking force load mechanism that applies a braking force to the wheels by the output of the electric motor, and a locked state that prevents the braking force slack operation of the braking force load mechanism and an allowed unlocked state A locking member that can be switched between a locked state and an unlocked state, a biasing means that biases the lock member to the unlocked state, and a biasing force generated by the biasing means. An electric brake device having a drive source for switching the lock member to a locked state against the drive,
A temperature sensor for detecting the outside air temperature of the vehicle or the temperature of the electric brake device is provided,
When the braking force loading mechanism applies a braking force and the locking mechanism is in the locked state, the temperature sensor detects the temperature T1 immediately before freezing of the set electric brake device, and the drive source is energized. Anti-freezing energizing means for controlling to start is provided,
The antifreeze energizing means, by energizing the driving source, the temperature detected by the temperature sensor, when it is detected that set high set point temperature T _H than the temperature T1, to the drive source An electric brake device that controls a current to be energized to be smaller than an original current.

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