JP4725468B2 - Electric parking brake system - Google Patents

Description

  The present invention relates to an electric parking brake system, and more particularly, to sliding of a friction material with a brake rotating body.

The electric parking brake system operates using an electric motor as a drive source, and controls the electric parking brake by controlling the electric motor and an electric parking brake that presses the friction material against the brake rotating body and maintains the vehicle in a stopped state. And a control device. The friction material is manufactured to have a shape and size that can be pressed along the brake rotator. If the friction material is pressed against the brake rotator in advance, the braking force is normally generated from the beginning of use. For this reason, conventionally, the frictional material is pressed against the brake rotating body and blended, in addition to the normal use of the electric parking brake system.
For example, in the electric parking brake system described in Patent Document 1 below, the electric motor is operated at the time of factory shipment to slightly press the friction material against the brake rotating body, causing a minute drag between them, The sliding is automatically performed as the vehicle travels. The dragging is automatically canceled in a state where a predetermined time has elapsed from the start of use of the vehicle and the sliding can be almost completed.
JP 2006-137257 A

However, in the electric parking brake system described in Patent Document 1, the friction material is pressed against the brake rotating body until a predetermined time elapses after the start of use of the vehicle. Depending on the situation, there is a problem of lack of stability of sliding.
The present invention has been made against the background of the above circumstances, and an object of the present invention is to provide an electric parking brake system in which sliding of a friction material with a brake rotating body is stably performed.

The above-described problems are: (A) an electric parking brake that operates using an electric motor as a drive source, presses the friction material against the brake rotating body to maintain the vehicle in a stopped state, and (B) controls the electric motor. A control device for an electric parking brake system including a control device for controlling the electric parking brake; (a) an operating force during parking that is an operating force for operating the electric parking brake to maintain the vehicle in a stopped state; Two types of signals are output: a first control unit to be applied; and (b) an action command signal for causing the electric parking brake to act at least according to an operation state and a release command signal for releasing the action. Depending on the manual operation of the manual operation switch, the sliding operation is smaller than the parking force and suitable for sliding the friction material with the brake rotating body. In and a second control unit for acting, in which case the second control unit, which was continued (c) the action state of the electric parking brake setting time, an automatic releasing unit for releasing the working state automatically, (d ) Even if a release command signal is received during the set time, the release command signal is ignored during the preset ignore time, and the operating state of the electric parking brake is maintained. In this case, even if the operation state of the electric parking brake does not continue for the set time, the automatic release unit includes a release command ignoring unit that releases the operation state of the electric barking brake. Even if an action command signal is received before the ignore time elapses after receiving the signal, the action command signal is ignored, and if the action state of the electric parking brake continues for the set time, the action state is automatically It is solved by constructing so that removal.
The operating force is a force that presses the friction material against the brake rotating body. For example, the electric parking brake has a configuration in which the cable is pulled by the operation of the electric motor and the friction material is pressed against the brake rotating body. It corresponds to the tension of the cable and can be obtained by detecting the tension. The operating force is maintained even when the current supply to the electric motor is interrupted, and the friction material is kept pressed against the brake rotating body. In this state, the pressing operation of the friction material against the brake rotating body is finished, and the electric parking brake is not in operation but is in operation.

For example, even if a release command is issued due to a mistake in the operation of the manual operation switch, and the manual operation switch is operated immediately thereafter and execution of sliding is instructed, the sliding is performed again and the set time is measured again. Therefore, it is avoided that the sliding is performed for an excessively long time, and the friction material is prevented from being excessively burnt by the long-time sliding.

Aspects of the Invention

  In the following, the invention that is claimed to be claimable in the present application (hereinafter referred to as “claimable invention”. The claimable invention is at least the “present invention” to the invention described in the claims. Some aspects of the present invention, including subordinate concept inventions of the present invention, superordinate concepts of the present invention, or inventions of different concepts) will be illustrated and described. As with the claims, each aspect is divided into sections, each section is numbered, and is described in a form that cites the numbers of other sections as necessary. This is for the purpose of facilitating the understanding of the claimable invention, and is not intended to limit the combinations of the constituent elements constituting the claimable invention to those described in the following sections. In other words, the claimable invention should be construed in consideration of the description accompanying each section, the description of the embodiments, etc., and as long as the interpretation is followed, another aspect is added to the form of each section. In addition, an aspect in which constituent elements are deleted from the aspect of each item can be an aspect of the claimable invention.

In each of the following items, the technical features described in the items (2), (5) to (7) are added to the item (1) and “when a release command signal is received during the set time. Even in such a case, the cancel command signal is ignored during the ignore time, and the operation state of the electric parking brake is maintained. Furthermore, when the ignore time has elapsed, the operation state of the electric parking brake is released. The characteristic feature is that even if an action command signal is received before the ignore time has elapsed after receiving a release command signal during the set time, the action command signal is ignored and the action state of the electric parking brake is set after the set time has elapsed. The addition of the technical feature “automatically cancel” corresponds to claim 1, and the addition of the technical feature described in (10) to claim 1, claim 2, claim 1 or Claim 2 (11 (1) is added with the technical features described in (3), and (4) is added to any one of (1) to (3) above in (1) to (3). The technical features described in (9) are added to any of claims 4 to 4, respectively, and correspond to claim 5 respectively.

(1) An electric parking brake that operates using an electric motor as a drive source and presses the friction material against the brake rotating body to maintain the vehicle in a stopped state, and a control that controls the electric parking brake by controlling the electric motor An electric parking brake system comprising: a control device;
A first control unit that applies an electric parking brake with an operating force during parking, which is an operating force when the electric parking brake is applied to maintain the vehicle in a stopped state;
An electric parking brake including: a second control unit that causes the electric parking brake to operate with a sliding operating force that is smaller than the parking operating force and is suitable for sliding the friction material with the brake rotating body. system.
At the time of sliding, the electric parking brake has an operating force of a set magnitude and is applied with an operating force suitable for sliding, and the sliding is performed satisfactorily while avoiding deformation and wear of the friction material. .
The features described in this section and below are particularly effective when the rubbing is performed using a brake test device or using a wheel rotation driving device dedicated to rubbing. It is also possible to adopt it when running while driving.
(2) The electric parking brake system according to (1), wherein the control device operates the second control unit in response to a manual operation of the sliding command operation device.
The second control unit may be automatically operated, but if operated according to a manual operation, for example, sliding can be performed at an arbitrary time, and if necessary, at an appropriate time. Sliding can be performed.
(3) The second control unit acts when the manual operation of the sliding command operating device is performed in a state where the transmission of the vehicle is in a free rotation allowable range. Electric parking brake system.
The free rotation allowable range is a range that allows free rotation of the output shaft of the transmission, and includes, for example, a neutral range and a parking range in a transmission that is configured to allow free rotation of the output shaft in the parking range.
In a state where the transmission of the vehicle is in the free rotation allowable range, the wheels can be freely rotated from the outside, and sliding can be performed in a state where the wheels are rotated by an external driving device.
(4) Item (2) or (3), wherein the second control unit operates when a manual operation of the sliding command operating device is performed in a state where the transmission of the vehicle is in a driving range. The electric parking brake system described in 1.
The drive range includes, for example, a drive range and a reverse range.
In a state where the vehicle transmission is in the driving range, the sliding can be performed in a state where the wheels are rotated by the driving device of the vehicle. For example, the sliding can be performed in more various modes by using the function of the vehicle. It can be carried out. Examples are the start time traveling speed maintenance request and the designated speed maintenance request described in the items (11) and (12), respectively.
(5) The electric parking brake system according to any one of (2) to (4), wherein the sliding command operation device includes a manual operation switch that outputs at least two types of signals according to an operation state.
The non-holding type, in which the manual operation switch continues to output the first signal while operating force is applied to the operating member, and changes to a state in which a second signal different from the first signal is output when the operating force is released Even a switch may be a holding type switch that once the operating member is operated to a predetermined operating position, continues to output the same signal even when the operating force is released, and the output signal changes only after the operating member is operated again. In either case, a manual operation switch that changes the output signal to three or more types may be used. The holding type switch can be physically held at the position where the operation member is operated, but it is not indispensable, and the state of the output signal can be held in cooperation with the switch unit and the circuit unit. Good.
The at least two types of signals output by the manual operation switch according to the operation state may be, for example, a signal for instructing execution of sliding and a signal for instructing nothing, or each of execution and end of sliding It may be a signal to command. Depending on how to use the output signal of the manual operation switch, sliding can be performed in various ways.
Further, the manual operation switch is easy to operate and can easily command sliding.
(6) The second control unit includes an automatic release unit that automatically cancels the operation state of the electric parking brake when the operation state of the electric parking brake is continued until a set condition is satisfied (1) to (5) The electric parking brake system according to any one of the items.
In a mode in which this item is subordinate to item (5), even if the manual operation switch outputs an action command signal for instructing to operate the electric parking brake in the action direction, if the set condition is satisfied, the electric parking can be performed. The brake is automatically released. An effect of facilitating the maintenance of the electric parking brake so that the set condition is satisfied without excess or deficiency is obtained.
(7) The electric parking brake system according to item (6), wherein the setting condition includes at least that the operating state of the electric parking brake continues for a set time.
For example, in a mode in which this item is subordinate to item (5), for example, when the start and end of sliding are commanded based on the operation of the manual operation switch, the sliding is started based on the operation of the manual operation switch. After that, even if the operation for finishing the sliding is delayed, due to the elapse of the set time, the sliding is automatically canceled before the manual operation switch is operated, and the sliding time is too long. Occurrence of overburning of the friction material due to excessive sliding is prevented. In addition, there is no variation in the sliding execution time, and coupled with the fact that the electric parking brake is automatically operated by the sliding operating force, the effect of the sliding is made more uniform.
Also, for example, when one of the two types of signals output by the manual operation switch is a signal for instructing execution of sliding, and the other is a signal for instructing nothing, the operation state of the manual operation switch indicates that the output signal is The operation is changed from a state where no signal is given to a state where a signal for instructing the execution of the output is output, and after the start of the alignment based on the execution instruction for the adjustment, the time is measured by a timer. When the set time has passed, the sliding can be automatically canceled, and the sliding can be performed without excess or deficiency, and the friction material hits the brake rotating body, that is, the sliding time is insufficient. Insufficient sliding due to the occurrence of the friction material and excessive burning of the friction material are prevented.
It can be the only condition that the action state lasts for the set time, it can be a condition that is selective to other conditions, or it can be one of multiple essential conditions. Is possible.
(8) Even if the second control unit receives the release command after the electric parking brake is once activated, the release command is issued at least during a predetermined ignorance time regarding the measurement of the set time. The electric parking brake system according to item (7), including a cancel command ignoring portion to be ignored.
Even if the release command is issued, the operation of the electric parking brake is not released immediately, the sliding is continued, and the time of the operating state of the electric parking brake for the sliding is continuously measured. For this reason, for example, in a mode in which this item is subordinate to item (5), for example, when the manual operation switch outputs a signal for instructing the release of sliding, a release command is issued due to an operation error of the manual operation switch. Even if the manual operation switch is operated immediately after that and the execution of the sliding is instructed, the sliding is not performed again and the set time is not measured again, and the sliding may be performed for an excessively long time. Avoided. If the operation of the second control unit is canceled by the release command and the measurement of the set time is reset, if the manual operation switch is operated immediately after that, the set time is measured again from the start of the sliding by the operation. This means that the sliding will be performed for an excessively long time in combination with the time of the sliding performed before the release, but in the mode in which this item is subordinate to (5), the sliding is performed. The time is not remeasured, and the friction material is prevented from being excessively burnt by long-time sliding.
(9) The control device can communicate with an external control device provided outside the vehicle in a wired or wireless manner, and the sliding command operation device includes an external command operation device provided in the external control device ( The electric parking brake system according to any one of items 2) to (8).
The control device itself of the electric parking brake system includes only an input unit that receives a command supplied from the external control device in accordance with an operation of the external command operation device, and performs a sliding operation including an operation command of the second control unit. All of the commands required for the operation may be supplied from the outside by the operation of the external command operation device, and the sliding command operation device may be configured only by the external command operation device, and the control device includes an input unit, The electric parking brake system has a built-in sliding command operation device, and the second control unit is operated in cooperation with a command based on the operation of the external command operating device and a command based on the operation of the built-in command operating device. The control device does not include an input unit, and all of the commands required for the sliding operation are sent to the electric parking brake system. The control device may include an input unit, and the operation command device may be built in the electric parking brake system so that the command required for operating the second control unit may be provided. A mode in which all commands are performed by a built-in command operation device and a mode in which all commands are performed by an external command operation device may be selectively performed.
If execution of the sliding control can be instructed from the external control device, the workability when performing the sliding in a factory or the like is improved. In addition, when the control device of the electric parking brake system includes only an input unit that receives a command supplied from the external control device according to the operation of the external command operation device, the manufacturer or repair shop that owns the external control device. Only can perform the sliding, and it can be avoided that the user performs the sliding in the illusion.
(10) The second control unit includes a rising gradient control unit that controls a rising gradient, which is an increasing gradient of the operating force when the electric parking brake is put into an operating state, to a predetermined magnitude. Or the electric parking brake system according to any one of (9).
When sliding is performed, the brake rotating body is rotated. According to the electric parking brake system described in this section, the friction material is gradually pressed against the brake rotating body. Sudden contact with and damage to the rotating body is avoided. Further, the deceleration of the wheel is suppressed, and the friction material is prevented from being damaged. Further, due to the suppression of deceleration, for example, when sliding is performed on the brake test device and the wheel is driven to rotate by the wheel rotation drive device of the brake test device, the vehicle is stably stationary on the test stand. The sliding is performed more stably.
(11) The vehicle includes a start time travel speed maintaining device that controls a drive device of the vehicle so as to maintain a start time travel speed that is a travel speed at the time when the control start command is issued, The control unit includes a start time travel speed maintenance request unit that requests operation of the start time travel speed maintaining device while the electric parking brake is kept in the applied state with the sliding actuation force. The electric parking brake system according to any one of items 1).
For example, when the start of control is commanded in a state where the running speed is suitable for sliding, sliding is performed in a state where the brake rotating body is rotated at a speed suitable for sliding, and thus more stable. Then, sliding is performed.
(12) including a designated speed maintaining device that controls a drive device of the vehicle so that the vehicle maintains an arbitrarily designated traveling speed, wherein the second control unit slides the electric parking brake for the sliding The electric parking brake system according to any one of (1) to (11), further including a designated speed maintenance requesting unit that requests operation of the designated speed maintenance device while maintaining the applied state with an actuation force.
The specified travel speed is set according to, for example, the type of friction material or brake rotating body (shape, dimensions, material, operation configuration, etc.), etc. The sliding is performed in a state of being rotated at a high speed, and is performed more stably.
(13) An electric parking brake that operates using an electric motor as a drive source and presses the friction material against a brake rotating body that rotates together with the wheels to maintain the vehicle in a stopped state, and the electric parking brake controls the electric motor. An electric parking brake system including a control device controlled by a method of sliding the friction material against the brake rotating body,
The wheel which should be prevented from rotating by the electric parking brake is rotated, and in this state, the friction material is applied to the brake rotating body and the vehicle is maintained in a stopped state according to an operation of a manual operation device. Electricity that presses with a sliding operating force that is set smaller than the parking operating force that is the operating force in the case, and releases the pressing of the friction material to the brake rotator when a set time has elapsed from the start of the pressing Parking brake sliding method.
According to the sliding method described in this section, for example, the same effect as the electric parking brake system described in the sections (1), (2) and (7) can be obtained.
(14) Even if a release command is supplied while the sliding operation is being performed with the sliding operation force, the release command is ignored for at least a predetermined ignorance time with respect to the measurement of the set time ( The sliding method of the electric parking brake as described in the item 13).
According to the sliding method described in this section, for example, the same effect as the electric parking brake system described in section (8) can be obtained.
(15) The electric parking brake sliding method according to (13) or (14), wherein the second control unit is operated while the wheels are rotated by a driving force of a driving source of the vehicle itself.
According to the sliding method described in this section, for example, the same effect as the electric parking brake system described in section (4) can be obtained.
(16) The electric parking brake sliding method according to (13) or (14), wherein the second control unit is operated while the wheels are rotated by a driving force from the outside of the vehicle.
According to the sliding method described in this section, for example, an effect similar to that of the electric parking brake system described in section (3) can be obtained.

  Several embodiments of the claimable invention will now be described in detail with reference to the drawings. In addition to the following examples, the claimable invention can be practiced in various modifications based on the knowledge of those skilled in the art, including the aspects described in the above [Aspect of the Invention] section. .

  FIG. 1 schematically shows an electric parking brake system according to an embodiment of the claimable invention. In FIG. 1, the code | symbol 10 shows the electric motor which is a drive source, and the code | symbol 12 shows the motion conversion mechanism with a clutch. The electric motor 10 is constituted by an electric motor capable of duty control, for example, a brushless DC motor. The motion conversion mechanism 12 with the clutch converts the rotation of the output shaft of the electric motor 10 into a linear motion of the output member, and prevents the electric motor 10 from being rotated by the force applied to the output member. Reference numerals 14 and 16 indicate left and right rear wheels, and reference numerals 18 and 20 indicate parking brakes provided on the wheels 14 and 16, respectively. The vehicle provided with the electric parking brake system is a rear-wheel drive vehicle, and parking brakes are provided on the left and right rear wheels 14 and 16 as drive wheels, respectively. The parking brakes 18 and 20 and the motion conversion mechanism 12 with the clutch are connected by cables 22 and 24, respectively. When the cables 22 and 24 are pulled by the operation of the electric motor 10, the parking brakes 18 and 20 are activated. In this embodiment, an electric parking brake 30 is constituted by the electric motor 10, the motion conversion mechanism 12 with clutch, the cables 22, 24, the parking brakes 18, 20, and the like. The electric motor 10 may be constituted by a brushed DC motor.

As shown in FIG. 2, the motion conversion mechanism 12 with a clutch includes a gear train 40, a clutch 42, a screw mechanism 44, and the like.
The gear train 40 includes a plurality of gears 46, 48 and 50. The gear 46 is engaged with the gear portion of the output shaft 52 of the electric motor 10 and rotated by the rotation of the output shaft 52, and the rotation of the gear 46 is transmitted to the gear 50 through the gear 48. On the end surface of the gear 50 opposite to the electric motor 10, a drive transmission portion 54 that protrudes in parallel with the axial direction is provided.

  The clutch 42 is a one-way clutch, and can rotate integrally with a housing 60, a coil spring 62 provided on the inner peripheral side of the housing 60, and an output shaft 64 of the clutch 42, as shown in FIG. Rotor 66. FIG. 3 shows a state in which the clutch 42 is cut along the line AA shown in FIG. The coil spring 62 is fitted to the housing 60 in a state where the winding diameter is elastically slightly contracted, and the outer peripheral surface thereof is in close contact with the inner peripheral surface of the housing 60, and the end portions 68, 70 are provided so as to protrude toward the inner peripheral side. The drive transmission portion 54 of the gear 50 is located in one of the two spaces sandwiched between the two end portions 68 and 70, and the rotor 66 is located in the other.

  When the gear 50 rotates along with the rotation of the electric motor 10, the drive transmission portion 54 comes into contact with one of the end portions 68 and 70, and the coil spring 62 is tightened to tighten the inner peripheral surface of the housing 60 and the spring 62. The frictional force with the outer peripheral surface is reduced. Thereby, the coil spring 62 and the rotor 66 can be rotated, and the output shaft 64 is rotated. The output shaft 64 is rotated integrally with the gear 50, and the rotation of the electric motor 10 is transmitted to the output shaft 64 by the clutch 42.

  When torque is applied to the output shaft 64 in a state where no electric current is supplied to the electric motor 10, the rotor 66 comes into contact with either one of the end portions 68 and 70, whereby the coil spring 62 is expanded in diameter. The frictional force between the outer peripheral surface of the coil spring 62 and the inner peripheral surface of the housing 60 is increased, and the rotation of the coil spring 62 is prevented. When the clutch 42 prevents the torque of the output shaft 64 from being transmitted to the gear 50 and no current is supplied to the electric motor 10, the electric motor 10 is not rotated by the torque applied to the output shaft 64. .

  As shown in FIG. 2, the screw mechanism 44 includes a housing 80, a male screw member 82 extending in a direction parallel to the axis L, a nut (not shown) screwed into the male screw member 82, and the nut axis line. And an equalizer 84 mounted so as to be rotatable around an axis perpendicular to the axis. The male screw member 82 is supported by the housing 80 through a pair of radial bearings 85 (the other is not shown) and a needle thrust bearing 86 so as to be relatively rotatable. The inner cables 87 of the cables 22 and 24 are connected to both arms of the equalizer 84, respectively. The main body of the equalizer 84 is provided with an engagement protrusion 88, which is not shown, but is engaged with a guide provided in the housing 80 in a direction parallel to the axis L. As a result, the equalizer 84 is not relatively rotatable with respect to the housing 80 around the axis L, is relatively movable in a direction parallel to the axis L, and is relatively rotated around the engaging projection 88 (around the axis M). It is possible to move.

  The equalizer 84 is movable relative to the housing 80 between a position indicated by a solid line and a position indicated by a two-dot chain line in FIG. 2, and the inner cable 22, 24 is moved along with the relative movement of the equalizer 84. The cable 87 is pulled or loosened. Further, the equalizer 84 is arranged around the engaging protrusion 88 (on the axis M) so that the tension applied to the inner cable 87 of the two cables 22 and 24 (hereinafter simply referred to as the tension of the cables 22 and 24) is the same. Around). A tension sensor 90 that detects the tension of the cable 24 is provided inside the housing 80. Since the tension applied to the cables 22 and 24 by the equalizer 84 is set to the same magnitude, the tension applied to the cable 24 detected by the tension sensor 90 is also the tension applied to the cable 22.

  Reference numeral 92 denotes an abnormality canceling device. The abnormal-time release device 92 is a device for releasing the parking brakes 18 and 20 when the electric motor 10 is abnormal. The abnormality canceling device 92 includes an outer cable 93 and an inner cable 94 that is a drive member provided in the outer cable 93 so as to be movable in the longitudinal direction, and an operator operates a grip (not shown) as an operation member. The cable 94 is engaged with the gear 96 so as not to be relatively rotatable, and the gear 96 is rotated. The rotation of the gear 96 is transmitted to the gear 50 through the gears 46 and 48, and the output shaft 64 is rotated by the rotation of the gear 50, and the equalizer 84 is moved in the direction of loosening the cables 22 and 24. Thereby, the parking brakes 18 and 20 are released.

  As shown in FIGS. 4 and 5, the parking brakes 18 and 20 are duo-servo type drum brakes in this embodiment. Therefore, hereinafter, the parking brakes 18 and 20 may be referred to as drum brakes as necessary. The electric parking brake 30 is an electric drum brake. In FIG. 4, reference numeral 97 denotes a brake disk, reference numeral 98 denotes a caliper, and the brake disk 97 and the caliper 98 together constitute a disk brake 99 as a service brake. The drum brakes as the parking brakes 18 and 20 are provided on the inner peripheral side of the brake disc 97, and are drum-in disc brakes in this embodiment. Since the drum brakes 18 and 20 have the same structure, the drum brake 18 will be described and the description of the drum brake 20 will be omitted.

  The drum brake 18 includes a backing plate 100 as a non-rotating member attached to a vehicle body (not shown) and a brake drum 104 (hereinafter referred to as a drum 104) as a brake rotating body having a friction surface 102 on its inner peripheral surface and rotating together with the wheels 14. Abbreviated). An anchor member 106 and an adjuster 108 as a relay link are provided at two positions separated in the diameter direction of the backing plate 100, respectively. The anchor member 106 is fixed to the backing plate 100, and the adjuster 108 is a floating type. Between the anchor member 106 and the adjuster 108, a pair of brake shoes 110a and 110b as friction materials each having an arc shape are attached so as to face the inner peripheral surface of the drum 104. The pair of brake shoes 110a and 110b are attached to the backing plate 100 so as to be movable along the surfaces thereof by shoe hold-down devices 112a and 112b. The through hole provided in the center of the backing plate 100 is for allowing the axle shaft (not shown) to pass therethrough.

  The pair of brake shoes 110a and 110b are operatively connected at one end to each other by an adjuster 108, and each other end abuts against the anchor member 106 and is rotatably supported. One end portions of the pair of brake shoes 110a and 110b are urged toward the adjuster 108 by an adjuster spring 114, and the other end portions are urged toward the anchor member 106 by a return spring 115. . Brake linings 116a and 116b as friction materials are held on the outer peripheral surfaces of the brake shoes 110a and 110b, and the pair of brake linings 116a and 116b are brought into contact with the friction surface 102 of the drum 104, whereby the brake linings 116a and 116b are arranged. A frictional force is generated between 116 b and the drum 104. The adjuster 108 is operated to adjust the gap between the pair of brake linings 116a and 116b and the drum 104 in accordance with the wear of the pair of brake shoes 110a and 110b.

FIG. 5 shows the pressing mechanism 120. The pressing mechanism 120 includes a brake lever 122 and a strut 124, and is supported by heads of bolts 138 and 140 that fix the anchor member 106 to the backing plate 100 so as to be relatively movable. Each of the brake lever 122 and the strut 124 is a plate-like member. When the brake lever 122 is sandwiched between two plate members constituting the strut 124, the brake lever 122 and the strut 124 have one end portion thereof. In FIG. 2, the shaft is connected so as to be relatively rotatable around the connecting shaft 126. In the brake lever 122, the brake shoe 110 a is engaged with an engaging portion 128 provided at a portion separated from the connecting shaft 126 toward the backing plate 100, and an end separated from the connecting shaft 126 in a direction parallel to the backing plate 100. The inner cable 87 of the cable 22 is connected to the engaging portion 130 provided in the portion. The inner cable 87 is guided by an outer tube 134 having one end fixed to a through-hole 132 provided in the backing plate 100, and extends to a side opposite to the side where the brake shoe 110 and the like of the backing plate 100 are disposed. It has been made.
Further, in the strut 124, the brake shoe 110 b is engaged with an engaging portion 135 provided at the end opposite to the connecting shaft 126.
In the state shown in the drawing, the engaging portion 130 is located on the backward rotation direction side of the center line N (of the fixed end of the outer tube 134 to the backing plate 100) of the through hole 132. Further, as will be described later, when the pressing mechanism 120 is relatively moved in the circumferential direction, the engaging portion 130 is also relatively moved, but by design, the pressing mechanism 120 is relatively moved from the center line N to a position on the forward rotation direction side. It is made not to be moved.

  The pressing mechanism 120 is supported by the heads of the bolts 138 and 140 at the supported portions 136 and 137. The electric motor 10 is rotated in the direction in which the parking brakes 18 and 20 are applied, the male screw member 82 is rotated, and the equalizer 84 is moved from the position indicated by the solid line to the position indicated by the two-dot chain line in FIG. When the cable 87 is pulled, the brake lever 122 rotates around the contact point between the supported portion 136 and the head of the bolt 138, and as a result, the connecting shaft 126 and the strut 124 are moved to the right in FIG. The strut 124 pushes the brake shoe 110b to the right. At that time, the reaction force from the brake shoe 110b is transmitted to the brake shoe 110a via the strut 124, the connecting shaft 126 and the brake lever 122, and the brake shoe 110a is pushed to the left in FIG. The brake shoes 110a and 110b are spread by being applied with the same spreading force. As a result, the brake linings 116a and 116b have the same magnitude on the friction surface 102 of the drum 104. Pressed with force. The tensile force applied to the cable 22 is boosted in accordance with the lever ratio of the brake lever 122, and the friction force between the supported portion 136 and the head of the bolt 138 is calculated from the boosted force. It is applied to the brake shoe 110a as the expanding force of the subtracted size.

  When the drum brake 18 is operated in a state where torque is applied to the drum 104, a circumferential force is applied from the drum 104 to the brake shoes 110a, 110b, and one of the brake shoes 110a, 110b is applied to the anchor member 106. A so-called duo-servo effect occurs. When torque in the forward rotation direction (the rotation direction of the wheel when the vehicle moves forward) P is applied, the brake shoe 110a is pressed against the drum 104 with a greater force than when only the expansion force is applied due to the self-servo effect (contact surface pressure). Is increased). The circumferential force due to the self-servo effect is transmitted to the brake shoe 110b by the adjuster 108 together with the spreading force, and the brake shoe 110b is pressed against the drum 104 more strongly than the brake shoe 110a. The brake shoe 110b is brought into contact with the anchor member 106, and braking torque is generated. When a torque in the reverse rotation direction (the rotation direction of the wheel when the vehicle moves backward) Q is applied, conversely, the brake shoe 110a is pressed against the drum 104 more strongly than the brake shoe 110b. One output of the pair of brake shoes 110a and 110b becomes the other input. In this case, the pressing force of the brake shoes 110a, 110b against the drum 104 has a magnitude corresponding to the tension of the cable 22, and the curve shown in FIG. There is a relationship represented by When the vehicle is in a stopped state and the friction coefficient between the brake linings 116a and 116b and the drum inner peripheral surface 102 is constant, the braking force, the frictional force, the pressing force, and the spreading force If a certain relationship is established and the expansion force increases, the pressing force, the frictional force, and the brakeable torque also increase. Therefore, for example, based on the relationship between tension and spreading force, it is possible to acquire the relationship between tension and pressing force, the relationship between tension and frictional force, and the relationship between tension and brakeable torque.

  The electric parking brake 30 is controlled by a parking brake (PKB) ECU (electronic control unit) 200 which is a control device shown in FIG. The parking brake ECU 200 includes an input / output unit 202, an execution unit 204, and a storage unit 206, and a parking brake switch 210 (hereinafter abbreviated as a PKB switch 210) and a tension sensor 90 are connected to the input / output unit 202.

  The PKB switch 210 is a manual operation switch. As shown in FIGS. 7 and 8, for example, the PKB switch 210 is rotatably provided on the instrument panel 218, and includes a lock side operation unit 220 and a release side operation unit 222. 7 is automatically positioned at an OFF position indicated by a solid line, a lock position indicated by a one-dot chain line, and a release position indicated by a two-dot chain line, and automatically returns to the OFF position when no operating force is applied. It is a return type switch. The PKB switch 210 outputs an OFF signal when it is in the OFF position. As will be described later, when the electric parking brake 30 is applied during traveling during normal use of the vehicle, the action is released based on the output of the OFF signal. The OFF signal of the PKB switch 210 is a release command signal for the operation of the electric parking brake 30. When the lock side operation unit 220 shown in FIG. 8 is pressed, the PKB switch 210 is rotated to the lock position and outputs a lock signal, and the electric parking brake 30 is actuated based on the lock signal. The lock signal of the PKB switch 210 is an action command signal for the electric parking brake 30. When the release side operation unit 222 of the PKB switch 210 is pressed, the PKB switch 210 is rotated to the release position and outputs a release signal. As will be described later, when the electric parking brake 30 is applied for parking during normal use of the vehicle, the action is released based on the output of the release signal. The release signal of the PKB switch 210 is a parking control release command signal.

  As shown in FIG. 1, the electric motor 10 is connected to the input / output unit 202 via the drive circuit 230 and driven. Further, a CAN (Car Area Network) 232 is connected to the input / output unit 202, whereby communication is performed between the parking brake ECU 200, the skid control computer 234, the engine control computer 236, and the like. The skid control computer 234 receives detection signals of various sensors such as a wheel speed sensor 238 and a front / rear G sensor 239, etc., and controls the brake actuator 240 and the like based on these signals to control braking, anti-lock control, and vehicle stability. Control and so on. From the skid control computer 234 to the parking brake ECU 200, for example, the traveling speed of the vehicle (hereinafter abbreviated as vehicle speed) is supplied.

  As shown in FIG. 1, the engine control computer 236 includes an engine control unit 250, a transmission control unit 252, and a cruise control control unit 254. The engine control computer 236 includes a shift position sensor 256, an accelerator sensor, a throttle position sensor, and the like not shown. Based on the detection signals of the sensors, the driving device 258 including the engine 262 and the transmission 264 as the driving source of the vehicle is controlled based on them, and the left and right rear wheels 14 and 16 are rotationally driven. In the cruise control, for example, by setting the cruise control switch 260 at a desired vehicle speed, the vehicle is driven at a desired vehicle speed at a desired vehicle speed by adding control of the driving device 258 and, if necessary, the brake actuator 240. Control, which is performed under the control of the cruise control control unit 254.

  In the electric parking brake system, a performance test, for example, a braking force test is performed by a brake test device 300 shown in FIG. The brake test device 300 includes a test stand 302 and a plurality of sets, for example, four sets of wheel rotation drive devices 304. Each of these wheel rotation driving devices 304 includes two rollers 306 and a roller rotation device 308, and is provided on the test table 302. The two rollers 306 are provided so as to be rotatable around axes parallel to each other. The roller rotating device 308 uses the electric motor 310 as a drive source, and the rotation of the electric motor 310 is transmitted to the two rollers 306 via the torque meter 312 and the rotation transmitting device 314, and the two rollers 306 are simultaneously at the same speed. It is rotated in the same direction. The torque meter 312 detects the counter torque that the electric motor 310 receives from the left and right rear wheels 14 and 16 via the rollers 306.

  The electric motor 310 of the roller rotating device 308 is controlled by a special operation control device 320 shown in FIG. The special operation control device 320 is provided outside the vehicle and in a factory where a brake test or the like is performed, and constitutes an external control device. The special operation control device 320 is mainly composed of a computer, and controls the electric motor 310 via a drive circuit (not shown). The counter torque detected by the torque meter 312 is input to the special operation control device 320 and is converted into a braking torque based on the wheel diameter and the like. The calculated braking torque is displayed on the display screen 324 by the display device 322.

  The special operation control device 320 is also connected with an input device 326 as an external command operation device such as a keyboard for inputting commands and the like. The special operation control device 320 is connected to the input / output unit 202 of the parking brake ECU 200 via a communication cable when the electric parking brake 30 is operated in the special control mode, performs communication, transmits a command, and the like. The special control mode is a control mode different from the normal control mode in which the electric parking brake 30 is applied during normal use of the vehicle. For example, the test control mode for performing a braking force test of the electric parking brake 30 and the brake shoes 110a, A sliding control mode for performing sliding matching with the drum 104 of 110b (hereinafter, simply referred to as “sliding unless otherwise necessary”) is included. The normal control mode includes, for example, a parking control mode for parking the vehicle and an emergency control mode for operating the parking brakes 18 and 20 as emergency brakes. The emergency control mode is a mode in which the electric parking brake 30 is applied in place of the service brake in order to suppress the rotation of the wheel when an abnormality occurs in the service brake that is applied based on depression of a brake pedal that is a kind of brake operation member. It is a kind of auxiliary control mode. These control modes are both an operation mode and an operation mode of the electric parking brake 30.

  The operation of the electric parking brake 30 in both the normal control mode and the special control mode is controlled by the parking brake ECU 200. For this reason, the storage unit 206 of the parking brake ECU 200 stores an electric parking brake control routine represented by a flowchart in FIG. 10 in addition to a main routine (not shown), and is repeatedly executed at regular minute time intervals. Hereinafter, four control modes of the electric parking brake system will be described based on this flowchart.

First, the operation of the electric parking brake system in the parking control mode will be described.
The parking control of the vehicle is started when the PKB switch 210 is turned on to the lock position in a state where the vehicle speed is equal to or lower than the set vehicle speed. The electric motor 10 is activated based on the output of the lock signal, and the brake shoes 110a and 110b are pressed against the drum 104 by the operating force during parking. The set vehicle speed is set to a magnitude at which it can be determined that the vehicle is stopped. The parking operating force is an operating force for maintaining the vehicle in a stopped state, and is set, for example, according to the gradient of the road surface and stored in the storage unit 206. The gradient of the road surface is acquired based on the longitudinal acceleration detected by the longitudinal G sensor 239, and the parking operating force is obtained by, for example, a map or an expression, and is set to be larger as the road surface gradient is larger. The part that acquires the road surface gradient based on the longitudinal acceleration of the front / rear G sensor 239 and the parking brake ECU 200 constitutes the road surface gradient detection device. In the case of parking control, even if the force applied to the PKB switch 210 is released and the PKB switch 210 returns to the OFF position, the electric parking brake 30 is in an applied state until the release side operation unit 222 is operated and a release signal is output. The parking control is continued and the vehicle is maintained in a stopped state.

  In step 1 of the electric parking brake control routine shown in FIG. 10 (hereinafter abbreviated as S1. The same applies to other steps), it is determined whether or not the PKB switch 210 has been switched to the lock position. This determination is made based on whether or not the output signal of the PKB switch 210 is a lock signal. If the PKB switch 210 is operated and switched to the lock position, the determination result of S1 is YES and S2 is executed. Whether or not parking control is being performed is determined. This determination is made based on whether the flag F1 is set to 1. The flag F1 is set to indicate that parking control is being executed.

  When the parking control is not started, the flag F1 is not set, the determination result of S2 is NO, S3 is executed, and it is determined whether execution of the factory mode is instructed. As for the electric parking brake system, special control including sliding control and test control is performed by operating the electric parking brake system at the factory. Execution is input to the special control device 320, and an execution command is transmitted from the special operation control device 320 to the parking brake ECU 200. The parking brake ECU 200 stores these execution commands while the sliding control or the test control is performed. The input for executing the factory mode is a kind of input for executing the special control mode.

  When the electric parking brake system is activated during normal driving of the vehicle, the execution command for the factory mode is not supplied. Therefore, the determination result in S3 is NO, S14 is executed, and whether or not the vehicle speed v is equal to or higher than the set vehicle speed α. Is determined. The vehicle speed v is supplied from the skid control computer 234 and read. If the vehicle speed v is smaller than the set vehicle speed α, the vehicle may be considered to be in a stopped state, the determination result in S14 is NO, S16 is executed, and parking control is executed. The electric motor 10 is activated, the brake shoes 110a and 110b are pressed against the friction surface 102 of the drum 104, the rotation of the wheels is prevented, and the vehicle is kept stationary. At this time, the current supply to the electric motor 10 is controlled based on the tension of the cables 22 and 24 detected by the tension sensor 90, the electric parking brake 30 is applied with a predetermined parking operating force, and the vehicle is stopped. To be maintained. The operating force is a force that presses the brake shoes 110a and 110b against the drum 104, and corresponds to the tension of the cable 22 and is acquired by detecting the tension. The operating force is maintained even when the current supply to the electric motor 10 is interrupted, and the brake shoes 110 a and 110 b are kept pressed against the drum 104. In S16, the flag F1 is also set, indicating that parking control is being performed.

  If the lock side operation unit 220 is continuously operated even after the parking control is started and the PKB switch 210 is switched to the lock position, the determination result of S1 is YES and S2 is executed, but the flag F1 is set. Therefore, the determination result in S2 is YES and S16 is executed. If the operation of the PKB switch 210 is released and the state returns to the OFF position, an OFF signal is output by the PKB switch 210, the determination result of S1 is NO, and S17 is executed, and a release signal is output. It is determined whether or not. The determination result is NO, and it is determined whether or not parking control is being performed in S18. This determination is made based on whether or not the flag F1 is set. However, since the flag F1 is set, the determination result in S18 is YES, S16 is executed, and parking control is continuously performed. If the release side operation unit 222 of the PKB switch 210 is operated and the PKB switch 210 is turned ON to the release position, the determination result of S1 is NO, the determination result of S17 is YES, S27 is executed, and parking control is performed. Be terminated. The electric motor 10 is rotated in the opposite direction to the case where the electric parking brake 30 is applied, the cables 22 and 24 are loosened, and the brake shoes 110a and 110b are separated from the drum 104 by the bias of the return spring 115. Thus, the electric parking brake 30 is released. In S27, the flag F1 is reset to 0.

The emergency control mode will be described.
The emergency control is started when the lock-side operation unit 220 of the PKB switch 210 is operated in a state where the vehicle speed is equal to or higher than the set speed, a lock signal is output, and a command for operating the electric parking brake 30 is output. The The electric parking brake 30 is operated with a preset operating force during travel. The driving force during the running is set in advance to a constant magnitude, is fixed, and is stored in the storage unit 206. As described above, the parking operating force is set according to the slope of the road surface and is not constant, but the running operating force is the variable parking operating force, whichever is smaller, and the parking operating force. It is set to a certain size within a range including an operating force smaller than the power, and is different from the parking operating force. The emergency control is performed while the PKB switch 210 is operated to the locked position, and is terminated when the force applied to the PKB switch 210 is released and the PKB switch 210 returns to the OFF position.

  When emergency control is performed, the PKB switch 210 is operated to the locked position, the determination result of S1 is YES, and S2 is executed, but since parking control is not performed, the determination result of S2 is NO become. Since the factory mode is not executed, the determination result of S3 is NO and S14 is executed. In a state where the emergency control is performed and the electric parking brake 30 is operated instead of the service brake, the vehicle is normally in a traveling state, the vehicle speed v is equal to or higher than the set vehicle speed α, and the determination result in S14 is YES S15 is executed and emergency control is performed. The electric motor 10 is activated, and the brake shoes 110a and 110b are pressed against the drum 104 to suppress the rotation of the wheels. The electric motor 10 is controlled based on the tension of the cables 22 and 24 detected by the tension sensor 90 so that an emergency operating force can be obtained. In S15, the flag F2 is also set to indicate execution of emergency control. While the vehicle speed v is equal to or higher than the set vehicle speed α and the PKB switch 210 is operated to the locked position, the determination result of S1 is YES, the determination results of S2 and S3 are NO, the determination result of S14 is YES, and S15 Is executed and emergency control is performed.

  If the operation of the PKB switch 210 by the driver is released, the PKB switch 210 returns to the OFF position and an OFF signal is output, the determination results of S1, S17, and S18 are NO and S19 is executed, and emergency control is performed. It is determined whether it is in the middle. This determination is made based on whether or not the flag F2 is set. However, since the flag F2 is set, the determination result in S19 is YES, S20 is executed, the electric parking brake 30 is released, and the emergency control is performed. Is terminated. Further, the flag F2 is reset.

The sliding control mode will be described.
The sliding is performed, for example, when the vehicle is assembled, repaired, or inspected. The electric parking brake system is performed on the brake test device 300 in the same manner as the braking force test, but parking brakes 18 and 20 are provided. The left and right rear wheels 14 and 16 are driven and rotated on the vehicle side. Therefore, the vehicle is placed on the test stand 302, and the four wheels are respectively placed on the two rollers 306 of the wheel rotation driving device 304, and the driving device 258 is operated in a supported state so that the left and right rear wheels 14, 16 is rotated. Here, the left and right rear wheels 14 and 16 are rotated in the vehicle forward direction, and forward sliding is performed. At this time, the electric motor 310 of the roller rotating device 308 of the brake test device 300 is allowed to rotate the left and right rear wheels 14, 16, and the roller 306 rotates along with the rotation of the left and right rear wheels 14, 16.

  The sliding is performed according to a preset procedure. When the vehicle is turned on, the shift lever as the operating range switching member is operated to set the operating range of the transmission 264 to the D (drive) range as the driving range, the accelerator pedal is depressed, and the driving device 258 is operated. The left and right rear wheels 14 and 16 are rotated in a direction to advance the vehicle. Also, the special operation control device 320 is connected to the parking brake ECU 200, a factory mode execution instruction is input to the special operation control device 320 using the input device 326, and the instruction command is sent from the special operation control device 320 to the parking brake ECU 200. Sent and stored.

  In this state, the lock side operation unit 220 of the PKB switch 210 is pressed, the PKB switch 210 is switched to the lock position, a lock signal is output, and execution of sliding is instructed. In principle, the sliding is performed while the PKB switch 210 is operated to the locked position, and is terminated if the operation is released. However, even if the operation is performed to the locked position, a set time from the start of the sliding is performed. When the time elapses, it is automatically terminated to avoid excessive sliding. In addition, even if the canceling of the rubbing is instructed before the set time for rubbing elapses, the rubbing is continued until another set time elapses. Even if the command is issued, the rubbing is not performed beyond the set time for the rubbing.

  If execution of the factory mode is instructed and the left and right rear wheels 14 and 16 are rotated and the PKB switch 210 is operated to the locked position, the determination result of S1 is YES, the determination result of S2 is NO, S3 , S4a is YES, S4b is executed, and it is determined whether or not the sliding is finished. This determination is made based on whether or not the flag F5 is set to 1. However, since the sliding has not been completed yet and F5 has been reset to 0, the determination result in S4b is NO and S5 Is executed, and it is determined whether or not the sliding is being executed. This determination is made based on whether or not the flag F3 is set. When S5 is executed for the first time, the flag F3 is reset, the determination result is NO, S6a is executed, and an instruction to maintain the vehicle speed at the traveling speed at the time of execution of S6a is output. This instruction is sent from the parking brake ECU 200 to the engine control computer 236, the drive device 258 is controlled by the cruise control control unit 254, and the left and right rear wheels 14, 16 are maintained so that the vehicle speed is maintained at the instructed magnitude. Rotated. When starting the sliding, the operator operates the PKB switch 210 to the lock position in a state where the vehicle speed becomes a desired vehicle speed. After S1 is executed, S6a is executed in a very short time, and an instruction is given to maintain the vehicle speed when the start of the sliding control is instructed, and the cruise control control unit 254 controls The vehicle speed is maintained at the indicated magnitude. This vehicle speed maintenance request is stored in the cruise control control unit 254 until the sliding is completed, and while the sliding is performed, the vehicle speed is maintained at the desired vehicle speed and the vehicle speed at the start of control, and the sliding is stabilized. Done. In S6a, the output control start time vehicle speed is also stored in the storage unit 206. Next, S6b is executed, and it is determined whether or not the vehicle speed is maintained at the instructed magnitude. Since the PKB switch 210 is operated to the lock position in a state where the vehicle speed has reached a desired vehicle speed, when S6b is executed, the vehicle speed is almost the vehicle speed instructed to maintain, and the determination result of S6b is extremely high. It becomes YES in a short time, and as shown in FIG. 11A, the sliding operation is started almost immediately by the ON operation of the PKB switch 210 to the lock position.

  And after flag F3 is set to 1 in S7, S8 is performed and sliding is performed. The electric motor 10 is activated, and the brake shoes 110a and 110b are pressed against the drum 104 with a sliding operation force. The electric motor 10 is controlled based on the tension of the cables 22 and 24 detected by the tension sensor 90 so as to obtain a sliding operation force. In this system, the sliding actuation force is smaller than the parking actuation force, and, as shown in FIG. 11 (a), the smaller one of the ranges of the actuation force within which the running actuation force is set. Therefore, a size suitable for sliding is set in advance and stored in the storage unit 206. The sliding actuation force is an actuation force when the electric parking brake 30 is operated in the special control mode, is a special actuation force, and is a regulated actuation force regulated to a magnitude smaller than the parking actuation force. The sliding is performed in the state in which the execution of the factory mode is instructed, the transmission is set to the D range, and the left and right rear wheels 14 and 16 are rotated. The electric parking brake 30 is operated with the sliding actuation force even if the required vehicle speed is equal to or higher than the set vehicle speed α used to select between parking control and emergency control. The sliding is performed.

  Further, the current supply to the electric motor 10 is duty controlled, and the duty ratio is changed according to a predetermined pattern, and the rising gradient, which is the increasing gradient of the operating force, is controlled to a predetermined magnitude. Even when the normal control mode is executed, the current supply to the electric motor 10 is duty-controlled, but during the sliding control, the duty control is performed so that the rising gradient of the operating force is smaller than that during parking control and emergency control. . A pattern of the duty ratio for this duty control is stored in the storage unit 206, and the tension of the cables 22 and 24 is normally indicated by a one-dot chain line as shown by a thick line in the time chart of FIG. The brake shoes 110 a and 110 b are gradually pressed against the drum 104 by increasing the gradient at a smaller gradient than that at the time of control.

  Next, S9 is executed, the count value C1 of the first counter is incremented by 1, and the time during which the sliding is performed is measured. The first counter is provided in the storage unit 206. Next, S10 is executed, and it is determined whether or not the count value C1 is greater than or equal to the set value CA. The time for performing the sliding is set in advance, and the set value CA represents the sliding time. In S10, it is determined whether or not the sliding has been performed for a set time. This determination is NO until the sliding time has elapsed, and the execution of the routine ends.

  Since the flag F3 is set to indicate that sliding control is being performed, while the PKB switch 210 is operated to the locked position, S1 to S5 and S8 to S10 are repeatedly executed until sliding ends, Matching is done. If the sliding time has elapsed, the determination result in S10 is YES, S11 is executed, and an end process is performed. The action of the electric parking brake 30 is released, and the flag F3, the first and second counters are reset. Further, the flag F5 is set to 1 to indicate that the sliding has been completed. Therefore, even if the sliding time has elapsed and the sliding has been sufficiently performed, if the PKB switch 210 is operated to the locked position, the determination result of S1 is YES, but the determination result of S4b is YES S5 to S11 are skipped, and no sliding is performed. As indicated by a thick line in FIG. 11 (a), the operation of the PKB switch 210 is released and the sliding is finished before returning to the OFF position, so that excessive sliding is avoided. Further, in S11, the storage of the execution of the factory mode is reset, and a traveling speed maintenance end command is output and transmitted to the engine control computer 236, and the traveling speed maintenance control by the cruise control control unit 254 is terminated.

  If the operation of the PKB switch 210 is released after the sliding is finished, the determination results of S1, S17 to S19, S21, and S25 are NO, S28 is executed, and it is determined whether or not the flag F5 is set. Is done. Since the sliding is performed for the set time and the flag F5 is set, the determination result in S28 is YES, S29 is executed, and the flag F5 is reset to 0. If the flag F5 is not set, the determination result in S28 is NO and the execution of the routine ends.

  If the operation of the PKB switch 210 is canceled before the sliding time elapses, the determination result of S1 is NO and S17 is executed, but this determination result is also NO, and the subsequent determinations of S18 and S19 The result is also NO, S21 is executed, and it is determined whether or not the sliding control is being performed. This determination is made depending on whether or not the flag F3 is set. However, since the sliding is started and the flag F3 is set, the determination result in S21 is YES and S22 is executed, and the second counter Count value C2 is incremented by one. The second counter is provided in the storage unit 206. The time from when the operation of the PKB switch 210 is canceled and the cancellation of sliding is instructed by the output of the OFF signal is measured.

  In S23, it is determined whether or not the count value C2 is equal to or greater than the set value CB. The set value CB is set to a value corresponding to an ignoring time for ignoring the sliding cancel command. For example, the disregard time is set to a time slightly longer than the time when it is predicted that re-execution will be re-commanded immediately because the cancel command is issued due to an operation error of the PKB switch 210. Until the neglected time elapses, the determination result in S23 is NO, S8 to S10 are executed, and the sliding is continued. Even if the release command is output, the sliding is not immediately finished, and the sliding time is continuously measured by the first counter.

  If the PKB switch 210 is operated to the locked position before the ignore time elapses, the determination result of S1 is YES, S2 to S5, S8 to S10 are executed, and this is performed when a release command is output. The rubbing is performed from the start of the rubbing until the set rubbing time elapses. It is assumed that there was no release command. Therefore, as shown by a two-dot chain line in the time chart of FIG. 11 (b), the operation of the electric parking brake 30 is released based on the output of the release command (OFF signal), and the sliding is finished. If the execution of rubbing is instructed immediately after that, the rubbing time is re-measured from the start of the rubbing by the output of the second rubbing execution command, and the rubbing performed when the release command is output However, when the release command is ignored, as shown by the thick line in FIG. 11 (b), the sliding is performed only for the set time. Is avoided. If the ignore time elapses without the PKB switch 210 being operated to the locked position after the release command is output, the determination result in S23 is YES, S24 is executed, and the sliding is finished. This end process is performed in the same manner as S11 except for the setting of the flag F5. In the time chart shown in FIG. 11 (b), the one-dot chain line indicates that the duty control for supplying current to the electric motor 10 at the start of sliding is performed in the same way as during the normal control of the electric parking brake 30. Comparison with this shows that the cable tension increase gradient during sliding control is small.

The braking force test will be described.
The braking force test is performed, for example, when the vehicle is assembled, repaired, or inspected. A vehicle equipped with the electric parking brake system is placed on the test table 302, and the left and right rear wheels 14 and 16 are moved by the wheel rotation driving device 304. This is performed by operating the electric parking brake 30 in the rotated state. During the braking force test, the left and right rear wheels 14, 16 are driven from the outside. Therefore, at the time of the test, the operation range of the transmission 264 is set to an N (neutral) range which is a free rotation allowable range so that the rotational driving of the left and right rear wheels 14 and 16 by the wheel rotation driving device 304 is not hindered. Here, the roller 306 of the wheel rotation device 304 is rotated in a direction to rotate the left and right rear wheels 14, 16 in the vehicle forward direction, and a forward braking force test is performed. In this case, the traveling speed of the vehicle, that is, the rotational speed of the wheel is determined by the performance of the wheel rotation driving device 304 and is not constant.

  The braking force test is performed according to a preset procedure as in the case of sliding. The vehicle is turned on and the shift lever is operated to set the operating range of the transmission 264 to the N range. Also, the special operation control device 320 is connected to the parking brake ECU 200, a factory mode execution instruction is input to the special operation control device 320 using the input device 326, and the instruction command is sent from the special operation control device 320 to the parking brake ECU 200. Sent and stored.

  In this state, the lock side operation unit 220 of the PKB switch 210 is pressed, the PKB switch 210 is switched to the lock position, a lock signal is output, and execution of the braking force test is instructed. The braking force test is performed while the PKB switch 210 is operated to the locked position. When the operation is released and the PKB switch 210 returns to the OFF position, the braking force test is terminated.

  If the tester operates the PKB switch 210 to switch to the locked position, the determination result of S1 is YES, the determination result of S2 is NO, the determination result of S3 is YES, the determination result of S4a is NO, and S12 is executed. Then, it is determined whether or not the operating range of the transmission 264 is the N range. If it is the N range, the determination result in S12 is YES, S13 is executed, and a braking force test is executed. The electric motor 10 is activated, the brake shoes 110a and 110b are pressed against the drum 104, and the rotation of the left and right rear wheels 14 and 16 is suppressed. At this time, the current to the electric motor 10 is duty controlled, the duty ratio is changed according to a predetermined pattern, the cable tension is gradually increased, and the brake shoes 110a and 110b are gradually pressed against the drum 104. . The operating force of the electric parking brake 30 is a preset operating force at the time of the test. In this electric parking brake system, the operating force is the same as the emergency operating force and is different from the variable parking braking force. It is a special operating force of magnitude. The electric motor 10 is controlled based on the tension detected by the tension sensor 90 so that this operating force can be obtained, and it is tested whether or not an appropriate driving force for the electric parking brake 30 can be obtained.

  If the brake shoes 110a, 110b are pressed against the drum 104 while the left and right rear wheels 14, 16 are rotated, a reaction force acts on the electric motor 310 of the roller rotating device 308, and the torque is detected by the torque meter 312. In addition to being sent to the special operation control device 320, it is converted into a braking force and displayed on the display screen 324. Based on the displayed braking force, the tester can determine whether or not the braking force of the electric parking brake 30 is normally obtained when the vehicle moves forward. Some brake test devices 300 that perform a braking force test have different rotational drive speeds for rotating the left and right rear wheels 14 and 16 during the test, and are equal to or higher than a set vehicle speed α that is used for selection between parking control and emergency control. In other words, in the electric parking brake system, the electric parking brake 30 is acted on by the operating force during the test regardless of the rotational speed of the left and right rear wheels 14, 16. The braking force test is performed stably. In S13, the flag F4 is also set to indicate execution of the braking force test.

  When the operation of the PKB switch 210 is released and the PKB switch 210 returns to the OFF position, the determination results of S1, S17 to S19, and S21 are NO and S25 is executed, and whether or not the braking force test is being executed. Is determined. This determination is made based on whether or not the flag F4 is set, but the determination result is YES, S26 is executed, and the braking force test is terminated. The operation of the electric parking brake 30 is released, and processing such as resetting the flag F4 is performed.

  When the PKB switch 210 is in the OFF position and none of parking control, emergency control, test control, and sliding control is performed, the determination results of S1, S17 to S19, S21, S25, and S28 are NO. The routine execution ends.

  As is clear from the above description, in this electric parking brake system, the PKB switch 210 constitutes a non-holding type manual operation switch, constitutes a sliding command operation device together with the input device 326, and the cruise control control unit 254. Constitutes the starting time travel speed maintaining device. Moreover, the part which performs S16 of parking brake ECU200 comprises the 1st control part which acts the electric parking brake 30 with the operating force at the time of parking. Further, the part that executes S9 to S11 of the parking brake ECU 200 constitutes an automatic release part, the part that executes S22 and S23 constitutes a release command ignoring part, and duty-controls the current supply to the electric motor 10 in S8. The part constitutes the rising slope control part at the time of the sliding control, the part that executes S6a constitutes the starting travel speed maintenance requesting part, and these are used for sliding the electric parking brake 30 according to the manual operation of the PKB switch 210. The 2nd control part made to act with an operating force is comprised. Further, the part for duty-controlling the current supply to the electric motor 10 in S13 of the parking brake ECU 200 constitutes the rising gradient control unit at the time of test control. Furthermore, the part that executes S14 of the parking brake ECU 200 constitutes an emergency control / parking control selection part that is a normal control mode selection part, and the part that executes S3 and S4a is a sliding control execution determination part that is a special control execution determination part. The portion that executes S3 and S12 constitutes a braking force test execution determination unit as a performance test execution determination unit that is a special control execution determination unit. The parking control mode performed by execution of S16 of the parking brake ECU 200 is the first control mode, the emergency control mode performed by the execution of S15 is the second control mode, and the special control mode performed by the execution of S8. The control mode is the third control mode. The braking force test control mode, which is a performance test control mode as a special control mode performed by the execution of S13, is the third control mode, and the part that executes S16 of the parking brake ECU 200 is a parking control unit that is a normal control unit, The first control unit that executes the first control mode is configured, the part that executes S15 is the emergency control unit that is the normal control unit, the second control unit that executes the second control mode is configured, and S8 is executed The part to be operated is a sliding control unit as a special control unit, and constitutes a third control unit for executing the third control mode, and the part for executing S13 is a braking force test control unit as a performance test control unit as a special control unit And the 3rd control part which performs the 3rd control mode is constituted. The fact that the execution of the factory mode is instructed and that the transmission 264 is set to the D range are conditions set in advance for performing the sliding, the execution of the factory mode is instructed, and the transmission 264 Is set to the N range is a condition set in advance for performing the braking force test.

  In addition, when performing the sliding control, the left and right rear wheels 14 and 16 may be rotated in the direction in which the vehicle is moved backward to perform the sliding for vehicle backward movement. In this case, the operating range of the transmission 264 is set to the R (reverse) range, and the left and right rear wheels 14 and 16 are rotated in the direction of moving the vehicle backward. The electric parking brake control routine, for example, after the determination result of S4a of the electric parking brake control routine shown in FIG. 10 is NO, before determining whether the operating range of the transmission 264 is the N range, It is determined whether or not it is in the R (reverse) range, and if it is in the R range, steps S4b and the subsequent steps are executed and sliding is performed.

  Further, the braking force test may be performed in a state where the wheels are rotated in the direction in which the vehicle is moved backward. In this case, the operating range of the transmission 264 is set to the N range, and the left and right rear wheels 14 and 16 are rotated in the direction of moving the vehicle backward by the wheel rotation driving device 304 of the brake test device 300. Others are performed in the same manner as the forward braking force test.

When performing the sliding control, when the wheels are rotated on the vehicle side, the drive device of the vehicle may be controlled so that the vehicle maintains a designated traveling speed that is arbitrarily designated. Examples thereof will be described with reference to FIGS. In addition, the same code | symbol is attached | subjected to the component which performs the same effect | action as the said Example, description is abbreviate | omitted.
The control of the driving device 258 for maintaining the specified traveling speed is performed using, for example, cruise control control. As shown in FIG. 12, the engine speed control device 400 is connected to the engine control computer 236. When maintaining the travel speed during normal travel, an arbitrary travel speed to be maintained is input and designated. . The cruise control control unit 402 has a function of controlling the driving device 258 based on the designation of the running speed, controlling the running speed of the vehicle to the designated running speed, and maintaining the magnitude. This type of cruise control control unit 402 is already known and will not be described further.

During the sliding control, an electric parking brake control routine shown in FIG. 13 is executed. This routine is configured in the same manner as the electric parking brake control routine shown in FIG. 10 except that the traveling speed of the vehicle is maintained at the designated traveling speed at the time of sliding.
The sliding is performed according to a preset procedure in the same manner as in the electric parking brake system described with reference to FIGS. 1 to 11. Further, the traveling speed specifying device 400 inputs a traveling speed to be maintained during the sliding. Is called. If the PKB switch 210 is turned ON to the locked position, the determination result of S1 is YES, the determination result of S2 is NO, each determination result of S3, S4a is YES, each determination result of S4b, S5 is NO, and S106a And a designated speed maintenance request is output to the engine control computer 236. Thereby, the cruise control control unit 402 starts control, and controls the rotation of the left and right rear wheels 14 and 16 so that the designated traveling speed is obtained. The designated speed maintenance request is canceled by the end of the sliding, and the cruise control control unit 402 controls the driving device 258 so that the designated traveling speed is maintained until a cancellation command is supplied.

Next, 106b is executed, and it is determined whether or not the vehicle speed has reached the specified travel speed. The determination result in S106b is NO until the vehicle speed reaches the specified travel speed. If the vehicle speed becomes the designated travel speed, the determination result in S106b is YES, the steps after S7 are executed, and the sliding is performed in a state where the vehicle speed is maintained at the magnitude designated by the travel speed designation device 400. . Since it is awaited that the vehicle speed becomes the designated travel speed, as shown in the time chart of FIG. 14, the sliding is started with a delay with respect to the ON operation to the lock position of the PKB switch 210 in the OFF position. The ON operation of the PKB switch 210 to the locked position is often performed in a state where the vehicle speed is suitable for sliding and almost reaches the vehicle speed specified by the travel speed specifying device 400. Execution waits for the vehicle speed to become the specified travel speed, but the time is short. When the sliding is completed, a designated speed maintenance control release command is output to the engine control computer 236 in the termination process at S11 or S24, whereby the cruise control control unit 402 terminates the designated speed maintenance control.
In this electric parking brake system, the cruise control control unit 402 constitutes a designated speed maintaining device, and the part that executes S106a of the parking brake ECU 200 constitutes a designated speed maintenance request unit.

  The electric parking brake system may be a system in which only one of the sliding control and the test control is performed as the special control.

  Further, the vehicle includes a start time travel speed maintaining device and a designated speed maintenance device, and the electric parking brake system includes a start time travel speed maintenance request unit and a specified speed maintenance request unit. The maintenance control may be selectively performed.

  Further, the sliding control is started by operating the PKB switch 210 to the locked position, the operation is released before the sliding time elapses, and thereafter, the execution of the sliding control is instructed by operating the PKB switch 210 again. If the neglected time has elapsed, for example, the notification device may notify that the sliding is insufficient, and if the execution of the sliding control is instructed later, the insufficient time Minutes and slides may be performed. For example, if a storage unit and a notification unit are provided and the execution time of the sliding control measured by the first counter at the time of releasing the sliding is shorter than a preset time for the sliding, the actual sliding execution is performed. The time is stored, and based on that, the notifying part notifies the lack of sliding, or a sliding compensation part is provided, and the lacking time of sliding is obtained and used at the time of the next sliding. A display unit may be provided, and the insufficient sliding time may be displayed by a display device.

  In addition, performance tests such as sliding and braking force tests are executed only by inputting commands from an external command operation device such as an input device of a special operation control device to an input unit of the control device of the electric parking brake system. It may be. At the time of special control, the electric parking brake is started in response to a command from the outside.

  Further, the performance test of the electric parking brake system may be, for example, a cable tension test during parking, in addition to the braking force test. For example, the relationship between the tension and the counter-torque received by the electric motor of the wheel rotation drive device by operating the electric parking brake while the wheel is rotated at a low speed by an external wheel rotation drive device and pressing the friction material slowly against the drum Ask for. The friction material may be pressed against the drum while the wheel is stopped, and the wheel may be rotated in that state.

Further, the sliding control may be performed in a state where the wheels are rotated by the wheel rotation driving device of the brake test device, or may be performed while the vehicle is actually running on a test course or the like. In the former case, as in the case of the braking force test, some brake test devices have different rotational drive speeds for rotating the wheels, and the vehicle speed exceeds the set vehicle speed used for selection between parking control and auxiliary control during traveling. Although it may be smaller than the set vehicle speed, the electric parking brake is operated with the sliding operation force regardless of the rotational speed of the wheel, and the sliding is performed stably.

  The claimable invention can also be applied to an electric parking brake system provided in a four-wheel drive vehicle or a front wheel drive vehicle, or an electric parking brake system in which the electric brake system includes a disc brake.

It is a figure showing roughly the electric parking brake system which is an example of the claimable invention. It is a front view (partial cross section) which shows the motion conversion mechanism with a clutch of the said electric parking brake system. It is side surface sectional drawing which shows the clutch of the said motion conversion mechanism with a clutch, and is AA sectional drawing in FIG. It is a front view which shows the drum brake which is a parking brake of the said electric parking brake system. It is a front view (partial cross section) which shows the pressing mechanism of the said electric parking brake system. It is a graph showing the relationship between the tension | tensile_strength of a cable at the time of the action | operation of the said electric parking brake system, and a brakeable torque. It is a front view which shows the parking brake switch which operates the said electric parking brake system. It is a top view which shows the said parking brake switch. It is a top view which shows roughly the brake test apparatus which tests about the said electric parking brake system. It is a flowchart which shows the electric parking brake control routine memorize | stored in the memory | storage part of parking brake ECU of the said electric parking brake system. It is a time chart representing the relationship between the operation of the parking brake switch and the passage of time and the tension of the cable when sliding is performed in the electric parking brake system, and the operation of the parking brake switch is not released halfway, It is a time chart showing when the set time has passed and when the sliding is instructed again immediately after being canceled halfway. It is a figure which shows schematically the electric parking brake system which is another Example. It is a flowchart which shows the electric parking brake control routine memorize | stored in the memory | storage part of parking brake ECU of the electric parking brake system shown in FIG. FIG. 13 is a time chart showing the relationship between the operation of the parking brake switch and the passage of time and the tension of the cable when sliding is performed in the electric parking brake system shown in FIG. 12.

Explanation of symbols

  10: Electric motor 14: Left rear wheel 16: Right rear wheel 18, 20: Parking brake 30: Electric parking brake 90: Tension sensor 100: Backing plate 102: Friction surface 104: Drum 110a: Brake shoe 110b: Brake shoe 120: Pushing mechanism 200: Parking brake ECU 210: PKB switch 220: Lock side operation unit 222: Release side operation unit 254: Cruise control control unit 258: Drive device 262: Engine 264: Transmission 300: Brake test device 304: Wheel rotation drive device 216: Special operation control device

Claims (5)

An electric parking brake that operates using an electric motor as a drive source and presses the friction material against the brake rotating body to maintain the vehicle in a stopped state, and a control device that controls the electric parking brake by controlling the electric motor An electric parking brake system including:
The control device is
A first control unit that applies an electric parking brake with an operating force during parking, which is an operating force when the electric parking brake is applied to maintain the vehicle in a stopped state;
Manual operation for outputting two types of signals, that is, an operation command signal for applying at least the electric parking brake in response to an operation state of the electric parking brake and a release command signal for releasing the operation state of the parking brake. A second control unit that is actuated by a sliding actuation force having a magnitude that is smaller than the parking actuation force and that is suitable for sliding the friction material with the brake rotating body according to a manual operation of the switch ,
The second control unit is
An automatic release unit that automatically releases the operation state when the operation state of the electric parking brake continues for a set time;
Even when the release command signal is received by manual operation of the manual operation switch during the set time, the release command signal is ignored during a predetermined ignore time, and the operation of the electric parking brake is performed. The release command ignoring unit that releases the operating state of the electric barking brake even if the operating state of the electric parking brake has not continued for the set time when the ignored time has passed. Including
The automatic release unit is
After receiving the release command signal during the set time, even if the operation command signal is received by manual operation of the manual operation switch before the ignoring time elapses, the operation command signal is ignored, and the electric parking brake An electric parking brake system configured to automatically release an operation state when the operation state continues for the set time . The said 2nd control part contains the rising gradient control part which controls the rising gradient which is an increase gradient of the operating force at the time of making the said electric parking brake into an action | operation state to a predetermined magnitude | size. electric parking brake system according to 1. The vehicle includes a start time travel speed maintaining device that controls a drive device of the vehicle so as to maintain a start time travel speed that is a travel speed at the time when a control start command is issued, and the second control unit includes: , while keeping the electric parking brake in the activated condition in the sliding aligning operation force, according to claim 1 or claims characterized in that it comprises a start time running speed maintenance request unit that requests the actuation of the start time running speed maintainer Item 3. The electric parking brake system according to Item 2 . A designated speed maintaining device that controls a driving device of the vehicle so as to maintain a designated traveling speed that is arbitrarily designated by the vehicle, and the second control unit uses the sliding parking force to drive the electric parking brake. The electric parking brake system according to any one of claims 1 to 3 , further comprising a designated speed maintenance requesting unit that requests operation of the designated speed maintenance device while maintaining the operating state. The control device can communicate with an external control device provided outside the vehicle by wire or wirelessly, and the manual operation switch includes an external command operation device provided in the external control device. The electric parking brake system according to any one of 4.

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