JP7650657B2 - Engine start battery protection control device - Google Patents

Description

This disclosure relates to a protection control device for an engine start battery.

Patent Document 1 discloses a power supply monitoring device. This power supply monitoring device includes a remaining charge detection means for detecting the remaining charge of a storage battery that serves as a power source when starting a vehicle engine, and a storage means for storing a plurality of remaining charge determination values that are preset for a plurality of on-board devices that use the storage battery as a power source. Each time the remaining charge of the storage battery falls below a respective remaining charge determination value, this power supply monitoring device restricts the operation of the on-board device that corresponds to the remaining charge determination value.

JP 2010-76509 A

However, the power supply monitoring device (protection control device for engine start batteries) disclosed in Patent Document 1 is intended to appropriately suppress over-discharge of the storage battery (engine start battery), and does not adequately protect the storage battery (engine start battery) from over-discharge.

This disclosure was made in consideration of the above-mentioned problems, and aims to provide a protection control device for an engine starting battery that can adequately protect the engine starting battery from over-discharge.

In order to achieve the above object, the protection control device for an engine start battery according to the present disclosure includes:
A protection and control device for an engine starting battery that serves as a power source for a starter motor that cranks an engine,
A control ECU that controls charging and discharging of one or more battery cells that constitute the engine start battery;
a protection circuit for protecting the one or more battery cells from overcharging and over-discharging;
Equipped with
The control ECU limits the supply of electricity to the starter motor when the battery voltage falls below a predetermined first predetermined value when the engine switch is turned on.

According to the engine start battery protection control device disclosed herein, the control ECU limits the supply of electricity to the starter motor if the battery voltage when the engine switch is on falls below a first predetermined value, thereby appropriately protecting the engine start battery from over-discharging.

1 is a perspective view showing an engine in which a protection device for an engine starting battery according to an embodiment of the present disclosure is adopted; FIG. 2 is a circuit diagram illustrating a control configuration of the engine illustrated in FIG. 1 . FIG. 2 is a front view of a battery unit mounted on the engine shown in FIG. 1 . FIG. 4 is a left side view of the battery unit shown in FIG. 3 . FIG. 4 is a right side view of the battery unit shown in FIG. 3 . 4 is a circuit diagram illustrating a control configuration of the battery unit illustrated in FIG. 3. FIG. 1 is a perspective view showing a schematic view of a mounting structure for a battery unit according to an embodiment of the present disclosure, with a cover removed; 4 is a flowchart illustrating an outline of the control process of the protection device for the engine start battery according to the embodiment of the present disclosure.

The following describes an engine starting battery protection device according to an embodiment of the present disclosure with reference to the attached drawings. However, the dimensions, materials, shapes, relative positions, etc. of the components described as embodiments or shown in the drawings are not intended to limit the scope of the present invention and are merely illustrative examples.

Figure 1 is a perspective view showing an engine 1 in which an engine start battery protection device according to an embodiment of the present disclosure is adopted, and Figure 2 is a diagram showing a schematic diagram of the control configuration of the engine 1 shown in Figure 1.

The engine starting battery protection device according to the embodiment of the present disclosure is mounted on the engine 1 or a work machine (not shown) on which the engine 1 is mounted. In the embodiment of the present disclosure, a protection device for an engine starting battery mounted on the engine 1 is described as an example, but the scope of the present invention is not limited thereto, and also includes a protection device for an engine starting battery mounted on a work machine on which the engine 1 is mounted.

The engine 1 according to the embodiment of the present disclosure is a single-cylinder or two-cylinder air-cooled gasoline engine with a displacement of 80cc to 800cc, and is mounted on a work machine such as a rice transplanter, cultivator, tiller, pump, or generator.

As shown in FIG. 1, the engine 1 according to the embodiment of the present disclosure includes a starter motor 3 (see FIG. 2) in addition to a recoil starter 12. The recoil starter 12 is a device that rotates the crankshaft of the engine 1 and starts the engine 1 when a person who wants to start the engine 1 grasps a starter grip 121 and pulls a rope wound around a pulley. The starter motor 3 is a motor that rotates the crankshaft of the engine 1 in place of the recoil starter 12, and in the engine 1 according to the embodiment of the present disclosure, the battery unit 6 (see FIG. 2) is the power supply source for the auxiliary equipment including the starter motor 3.

The engine 1 according to the embodiment of the present disclosure also includes an engine switch 21 and an engine start operation switch 22. The engine switch 21 is a switch for turning the power on and off, and is disposed on the side of the engine 1 according to the embodiment of the present disclosure. The engine switch 21 is, for example, a rocker switch (also called a seesaw switch), and is turned on when starting the engine 1 and turned off when stopping the operation of the engine 1. The engine start operation switch 22 is a switch for starting the engine 1, and is disposed alongside the engine switch 21 on the side of the engine 1 according to the embodiment of the present disclosure. The engine start operation switch 22 is, for example, a momentary push switch, and is pressed down when starting the engine 1 by the starter motor 3.

The engine 1 according to the embodiment of the present disclosure further includes a switch 23 for an external device. The switch 23 for an external device is, for example, a choke changeover switch 231, which is disposed on the side of the engine 1 according to the embodiment of the present disclosure. The choke changeover switch 231 is, for example, a rocker switch, and is capable of switching between auto choke and manual choke.

As shown in FIG. 2, the engine 1 according to the embodiment of the present disclosure further includes a starter relay 4, a charge coil 13, and an ignition coil 15. The starter relay 4 is a relay (magnetic relay switch) that opens and closes a contact 41 provided between the battery unit 6 and the starter 3. When the contact 41 is closed, electricity is supplied from the battery unit 6 to the starter 3. The charge coil 13 is provided inside the flywheel and is a coil for generating electricity by the rotation of the flywheel. The electricity generated by the charge coil 13 is supplied to the battery unit 6 via the regulator 14 and charged. Since the charge coil 13 always generates electricity when the engine 1 is rotating, it may have a function of grasping the operating state of the engine 1, for example, by monitoring the presence or absence of power generation in the battery unit 6. This function makes it possible to start the engine 1 safely. The ignition coil 15 is installed on the outside of the flywheel and is an integrated generator/transformer device that converts the electricity generated inside the ignition coil 15 by the rotation of the flywheel into high-voltage electricity, and the high-voltage electricity converted by the ignition coil 15 is discharged by the spark plug 16.

The battery unit 6 according to the embodiment of the present disclosure is an electrical supply source for auxiliary equipment including the starter motor 3 as described above, and supplies electricity to the starter motor 3 when the engine 1 is started, while also charging the engine 1 with electricity generated by the charge coil 13.

Figure 3 is a front view of the battery unit 6 mounted on the engine 1 shown in Figure 1. Figure 4 is a left side view of the battery unit 6 shown in Figure 3, and Figure 5 is a right side view of the battery unit 6 shown in Figure 3. Also, Figure 6 is a circuit diagram showing the control configuration of the battery unit 6 shown in Figure 3.

As shown in FIG. 3, the battery unit 6 according to the embodiment of the present disclosure has a horizontally elongated, generally rectangular parallelepiped shape and has a protrusion 6a that protrudes upward. The battery unit 6 has a generally rectangular parallelepiped shape with a length of 220 mm, a height of 75 mm, and a width of 45 mm, excluding the protrusion 6a, for example, and its weight is kept to 800 g or less, making it highly portable.

The battery unit 6 according to the embodiment of the present disclosure includes a battery pack 61 and an engine start control device 7 (see FIG. 6), which are housed in a housing 62 that is a horizontally elongated, roughly rectangular parallelepiped shape and has a protrusion 62a that protrudes upward.

The battery pack 61 is composed of, for example, a lithium ion battery. In the battery unit 6 according to an embodiment of the present disclosure, the battery pack 61 is composed of one or more battery cells 611. The individual voltage of the battery cell 611 is 3.0 to 4.2 V, and the total capacity is 6000 to 20000 mAH, which ensures portability as a battery unit 6. As shown in FIG. 6, the battery unit 6 according to an embodiment of the present disclosure is composed of, for example, four battery cells 611.

The engine start control device 7 is composed of a control ECU 71 (Electronic Control Unit) that controls the charging and discharging of the battery pack 61. The control ECU 71 is composed of, for example, a processor including a control device and an arithmetic device, and a control board equipped with memories such as a ROM (Read Only Memory) and a RAM (Random Access Memory). In the engine start control device 7 according to the embodiment of the present disclosure, the control ECU 71 manages the temperature (battery temperature) of the battery pack 61, the voltage (total voltage) of the battery pack 61, and the voltage (cell voltage) of each battery cell. In addition, the control ECU 71 protects the battery cells 611 from over-discharging by a protection circuit 711 for each battery cell 611. The protection circuit 711 is composed of, for example, a protection IC (integrated circuit).

In addition, in the battery unit 6 according to the embodiment of the present disclosure, a wiring coupler 63 is connected to the battery unit 6. A paired wiring coupler 24 (see FIG. 2) can be attached and detached to the wiring coupler 63, and the battery unit 6 is connected to input/output devices provided outside the battery unit 6 by attaching the paired wiring coupler 24. The input/output devices provided outside the battery unit 6 are, for example, the above-mentioned engine switch 21, engine start operation switch 22, starter relay 4, etc., and are connected to the paired wiring coupler 24 described above via two or more wire harnesses included in the control harness 25. Then, by attaching the paired wiring coupler 24 to the above-mentioned wiring coupler 63, multiple input/output devices such as the engine switch 21, engine start operation switch 22, and starter relay 4 are connected to the battery unit 6 at once.

In the battery unit 6 according to the embodiment of the present disclosure, an engine charging input terminal 712, a power supply detection terminal 713, an engine start operation detection terminal 714, a starter relay control terminal 715, an external device output terminal 716, and a constant voltage output terminal 717 are provided in the battery unit 6. The engine charging input terminal 712, the power supply detection terminal 713, the engine start operation detection terminal 714, the starter relay control terminal 715, and the external device output terminal 716 are connected to the control ECU 71, and the charge/discharge current from these terminals is managed by the control ECU 71. The constant voltage output terminal 717 is directly connected to the battery pack 61, and the battery voltage (total voltage) of the battery pack 61 is applied to the constant voltage output terminal 717. The wiring couplers 63 to which these terminals are respectively connected are installed on the protrusions 62a (see FIG. 3) of the housing 62 that have a waterproof/dustproof structure.

As shown in FIG. 2, the input/output devices connected to the battery unit 6 are the regulator 14 connected to the charge coil 13, the engine switch 21, the engine start operation switch 22, the starter motor relay 4, external devices 5 such as the valve control unit 51 and the choke valve 52, and the engine switch 21 (battery voltage is constantly applied), which are each connected to a pair of wiring couplers 24 via an engine charging input line 251, an engine switch operation detection line 252, an engine start operation detection line 253, a starter motor relay control line 254, a valve device output line 255, and a battery voltage constant application line 256.

In the battery unit 6 according to the embodiment of the present disclosure, electricity is supplied from the regulator 14 connected to the charge coil 13 through the engine charging input line 251 to the control ECU 71, and the control ECU 71 evenly charges the battery cells 611 while managing the temperature and voltage of the battery pack 61 and the voltage of each battery cell 611.

In the battery unit 6 according to the embodiment of the present disclosure, a starter motor power supply terminal 64 is provided on the housing 62 of the battery unit 6. The starter motor power supply terminal 64 is a terminal to which a power line (first power line) 641 for supplying electricity from the battery pack 61 to the starter motor 3 (starter motor relay 4) can be attached and detached, and is installed, for example, on the left side surface of the housing 62 of the battery unit 6 (see FIG. 5), and is waterproofed and dustproofed by a rubber cover.

A fuse 642 is provided on the power line 641 connecting the starter motor power supply terminal 64 and the starter motor relay 4. The fuse 642 protects the starter motor relay 4 and the starter motor 3 by melting when an overcurrent exceeding the rated current flows through the power line 641 due to over-discharging of the battery pack 61. As a result, even if the fuse 642 melts due to an overcurrent, the starter motor relay 4 and the starter motor 3 can be easily restored by replacing the power line 641.

As shown in FIG. 6, a battery protection relay 65 is provided between the starter motor power supply terminal 64 and the battery pack 61. The battery protection relay 65 has contacts between the battery pack 61 and the starter motor power supply terminal 64, and the contacts between the battery pack 61 and the starter motor power supply terminal 64 are closed in response to a command from the control ECU 71.

In the battery unit 6 according to the embodiment of the present disclosure, an external charging input terminal 66 is provided on the housing 62 of the battery unit 6. The external charging input terminal 66 is a terminal to which a power line (second power line) (not shown) for supplying electricity for charging from an external power source to the battery unit 6 can be attached and detached, and is installed, for example, on the right side surface of the housing 62 of the battery unit 6 (see FIG. 4), and is provided with a rubber cover to provide waterproof and dustproof measures.

The external power source is, for example, a household power source or a car battery. For example, when the external power source is a household power source, the power line of a dedicated charger is attached to the external charging input terminal 66, and electricity for charging is supplied from the household power source to the external charging input terminal 66. This causes the control ECU 71 to start from a standby state, and electricity is evenly charged to the battery cells 611 while managing the temperature and voltage of the battery pack 61 and the voltage of each battery cell 611. Also, for example, when the external power source is a car battery, a power line connected to the cigarette lighter socket of the car is attached to the external charging input terminal 66, and electricity for charging is supplied from the car battery to the external charging input terminal 66. This causes the control ECU 71 to start from a standby state, and electricity is evenly charged to the battery cells 611 while managing the temperature and voltage of the battery pack 61 and the voltage of each battery cell 611.

In the battery unit 6 according to an embodiment of the present disclosure, the external charging input terminal 66 is connected to the control ECU 71, and the charging electricity supplied to the external charging input terminal 66 is controlled by the control ECU 71, so that one or more battery cells 611 constituting the battery pack 61 are evenly charged.

In the battery unit 6 according to the embodiment of the present disclosure, a charging output terminal 67 is connected to the control ECU 71. The charging output terminal 67 is a terminal to which a charging input terminal provided on a portable device can be attached and detached, and by attaching the charging input terminal provided on the portable device, the control ECU 71 provided inside the battery unit 6 and the portable device provided outside the housing are connected, and electricity is supplied from the battery pack 61 to the portable device via the control ECU 71. The portable device is, for example, a mobile phone such as a smartphone, and the charging output terminal 67 is, for example, a USB output terminal 671, which is a female terminal of any of Types A, B, or C that can provide an output of up to 2 A.

In the battery unit 6 according to the embodiment of the present disclosure, the charging output terminal 67 is provided so as to extend from a protrusion 62a provided on the housing 62 of the battery unit 6 to the outside of the battery unit 6, and is provided with waterproof and dustproof measures.

As shown in FIG. 3, the battery unit 6 according to the embodiment of the present disclosure is provided with one or more indicators 68 and a remaining charge check button 69 on the front side of the housing of the battery unit 6. The one or more indicators 68 and the remaining charge check button 69 are connected to the control ECU 71. The one or more indicators 68 constitute, for example, a remaining charge indicator light and a status indicator light of the control ECU 71.

The remaining charge indicator lamp is composed of, for example, three to five LED lamps. For example, the three to five LED lamps are composed of two to four LED lamps of the same color and one LED lamp of a different color, and are controlled so that as the remaining charge of the battery pack 61 decreases, the number of LED lamps of the same color that are lit decreases, and finally an LED lamp of a different color is lit. When the remaining charge confirmation button 69 is pressed while the control ECU 71 is in a stopped state, the control ECU 71 is started from a standby state, and one or more indicators 68 are controlled to display the remaining charge of the battery pack 61 at that time.

The status indicator lamp of the control ECU 71 is composed of one to three LED lamps of different colors, and is controlled to light any LED lamp based on the state of the control ECU 71. For example, when the engine switch 21 is on and the engine 1 can be started, an LED lamp notifying that the engine can be started is lit, and after the engine 1 has started, an LED lamp notifying that the engine 1 is running is lit.

Figure 7 is a perspective view showing a schematic diagram of the mounting structure of the battery unit 6 according to an embodiment of the present disclosure, with the cover 9 removed.

As shown in FIG. 7, in the mounting structure of the battery unit 6 according to the embodiment of the present disclosure, the battery unit 6 is mounted on the side of the engine 1, but the scope of the present invention is not limited to this and includes mounting at any position on the work machine on which the engine 1 is mounted.

The mounting structure of the battery unit 6 mounted on the engine 1 in which the engine start control device 7 according to the embodiment of the present disclosure is adopted includes, in addition to the battery unit 6 described above, a case 8 and a cover 9.

The case 8 is attached to the engine 1 or the work machine on which the engine 1 is mounted. The case 8 is attached, for example, to the front of the engine 1. The case 8 is box-shaped with an open front and houses the battery unit 6. The case 8 is, for example, a horizontally elongated, approximately rectangular box with an open front, with a storage area in which the battery unit 6 is stored in its lower region and a connection space for the wiring couplers 24, 63 in its upper region. The storage area has a volume slightly larger than the volume of the battery unit 6, and the battery unit 6 is stored so as to be fitted into the storage area. The connection space has a volume sufficient to connect the wiring coupler 63 and the wiring coupler 24 that is paired with the wiring coupler 63, and the above-mentioned engine switch 21 and engine start operation switch 22 are installed on the right side of the connection space, and the above-mentioned switch 23 for the external device, for example, the choke changeover switch 231, is installed on the left side of the connection space.

The cover 9 is attached to the case 8 to close the opening of the case 8 in which the battery unit 6 is housed. The cover 9 is, for example, box-shaped with an opening at the rear, and is combined with the case 8 in which the battery unit 6 is housed to close the front opening of the case 8. The cover 9 is, for example, slightly larger than the case 8 in the longitudinal direction of the case 8, and a wiring space is provided in the right area of the case 8 for the power line 641 (see Figure 2) that connects the battery unit 6 (starter motor power supply terminal 64) and the starter motor relay 4.

The cover 9 is cut out in areas corresponding to the engine switch 21 and engine start operation switch 22 described above, and the engine switch 21 and engine start operation switch 22 are exposed outside the cover 9 when the cover 9 is attached to the case 8. The cover 9 is also provided with a rectangular window 9a in an area corresponding to the switch 23 for an external device, and the switch 23 for an external device is exposed outside the cover 9 when the cover 9 is attached to the case 8.

The cover 9 also has a rectangular window 9b in an area corresponding to, for example, one or more indicators 68 and the remaining charge check button 69, and when the cover 9 is attached to the case 8, the one or more indicators 68 and the remaining charge check button 69 are exposed outside the cover 9.

The cover 9 has through holes at one end and the other end in the longitudinal direction, and the cover 9 is attached to the case 8 by inserting a bolt 91 through the through holes and fitting it into a screw hole in the case 8. The bolt 91 that passes through the through hole is, for example, a bolt with a slot into which a coin fits, or a butterfly bolt.

In addition, in the mounting structure of the battery unit 6 according to the embodiment of the present disclosure, the above-mentioned battery unit 6 has a cushioning material 6b attached to the front surface facing the cover 9. This makes it possible to suppress vibrations transmitted from the engine 1 and the work machine to the battery unit 6 and to protect the battery unit 6.

The engine starting battery protection device according to the embodiment of the present disclosure is a protection device for an engine starting battery that serves as a power source for a starter motor 3 that cranks an engine 1. The engine starting battery according to the embodiment of the present disclosure is a battery pack 61 provided in a battery unit 6, and the engine starting battery protection device is composed of a control ECU 71 and a protection circuit 711.

As described above, the control ECU 71 according to the embodiment of the present disclosure controls the charging and discharging of one or more battery cells 611 constituting the battery pack 61, and the protection circuit 711 according to the embodiment of the present disclosure protects one or more battery cells 611 from overcharging and overdischarging. The control ECU 71 according to the embodiment of the present disclosure cuts off the supply of electricity to the starter motor 3 when the battery voltage when the engine switch 21 is on falls below a first predetermined value. The first predetermined value is, for example, a value at which the remaining charge of the battery pack 61 is 30%, and can be changed depending on the temperature (battery temperature) of the battery pack 61. The first predetermined value is, for example, 12.9 V, and is changed to 12.7 V when the temperature is below 0° C.

In addition, the control ECU 71 according to the embodiment of the present disclosure limits discharge from the input/output terminal via the control ECU 71 when the battery voltage when the engine switch 21 is on falls below a second predetermined value that is lower than the first predetermined value. The second predetermined value is, for example, a value at which the remaining charge of the battery pack 61 is 5%, for example, 12 V. In addition, when the control ECU 71 detects that the battery voltage continues to be below the second predetermined value for a predetermined time (first predetermined time), it causes the LED lamp indicating the lower limit state of the remaining charge indicator lamp (indicator 68) to flash. Then, when a predetermined time (second predetermined time) has elapsed since the LED lamp started flashing, the control ECU 71 turns off the power to the control ECU 71.

Even if the battery voltage falls below the second predetermined value and discharging from the input/output terminal via the control ECU 71 is restricted, when electricity generated by the engine 1 (charge coil 13) is supplied to the control ECU 71 or electricity is supplied to the control ECU 71 from an external power source, the control ECU 71 starts up and starts charging the battery pack 61.

In addition, the control ECU 71 according to the embodiment of the present disclosure electrically disconnects the battery pack 61 and the control ECU 71 when the battery voltage when the engine switch 21 is on falls below a third predetermined value that is smaller than the second predetermined value. The third predetermined value is, for example, a value at which the power consumption of the control ECU 71 becomes an issue, such as 10 V.

Even if the battery voltage falls below the third predetermined value and the battery pack 61 and the control ECU 71 are electrically disconnected, when electricity generated by the engine 1 (charge coil 13) is supplied to the control ECU 71 or electricity is supplied to the control ECU 71 from an external power source, the electrical disconnection between the battery pack 61 and the control ECU 71 is released and charging of the battery pack 61 begins. Then, if the supply of electricity is interrupted before the battery voltage recovers to the third predetermined value , the battery pack 61 and the control ECU 71 are electrically disconnected again.

In addition, the control ECU 71 according to the embodiment of the present disclosure electrically disconnects the battery pack 61 and the control ECU 71 when the voltage (cell voltage) of at least one of the one or more battery cells 611 falls below a fourth predetermined value. The fourth predetermined value is, for example, the voltage of the battery cell 611 when it is over-discharged, and the input/output terminals are disconnected except for the power supply detection terminal 713, and electricity generated by the engine 1 (charge coil 13) and electricity from an external power source cannot be supplied (protection circuit 711 is activated).

Furthermore, the control ECU 71 according to an embodiment of the present disclosure restricts input and output via the control ECU 71 when the temperature rise rate of the battery cell 611 exceeds a predetermined temperature rise rate. The predetermined temperature rise rate is for determining abnormal heat generation in the battery cell 611, and is set, for example, based on the temperature rise rate when heat is generated due to over-discharge. For example, the predetermined temperature rise rate is a rise rate at which the temperature of the battery cell 611 rises by 3°C in three seconds, and when the temperature of the battery cell 611 rises by 3°C in three seconds, all input and output via the control ECU 71 is blocked.

Figure 8 is a flowchart that shows the outline of the control process of the engine start battery protection device according to an embodiment of the present disclosure.

As shown in FIG. 8, in the protection device for an engine starting battery according to an embodiment of the present disclosure, when the engine switch 21 is turned on (step S21: Yes), the power is turned on and the control ECU 71 switches from a standby state to a start-up state (step S22).

Next, the control ECU 71 compares the battery voltage of the battery pack 61 with a first predetermined value (step S23). If the battery voltage of the battery pack 61 falls below the first predetermined value (step S23: Yes), the control ECU 71 cuts off the supply of electricity to the starter motor 3 (step S24). As a result, even if the engine start operation switch 22 is operated to start the engine 1, electricity is not supplied to the starter motor 3, and the starter motor 3 does not crank the engine 1.

If the battery voltage of the battery pack 61 falls below the first predetermined value (step S23: Yes), the control ECU 71 compares the battery voltage of the battery pack 61 with a second predetermined value (step S25). If the battery voltage of the battery pack 61 falls below the second predetermined value (step S25: Yes), the control ECU 71 limits the discharge from the input/output terminal via the control ECU 71 (step S26). Then, when the control ECU 71 detects that the battery voltage continues to fall below the second predetermined value for a predetermined time (first predetermined time), the control ECU 71 blinks the LED lamp indicating the lower limit state of the remaining charge indicator lamp (indicator 68) (step S27). Then, when a predetermined time (second predetermined time) has elapsed since the LED lamp blinked, the control ECU 71 turns off the power to the control ECU 71 (step S28).

If the battery voltage of the battery pack 61 falls below the second predetermined value (step S25: Yes), the control ECU 71 compares the battery voltage of the battery pack 61 with a third predetermined value (step S29). If the battery voltage of the battery pack 61 falls below the third predetermined value (step S29: Yes), the control ECU 71 electrically disconnects the battery pack 61 from the control ECU 71 (step S30).

If the battery voltage of the battery pack 61 does not fall below the third predetermined value (step S29: No), the voltage (cell voltage) of the battery cell 611 is compared with a fourth predetermined value (step S31). If the voltage (cell voltage) of at least one of the one or more battery cells 611 falls below the fourth predetermined value (step S31: Yes), the battery pack 61 and the control ECU 71 are electrically disconnected (step S30).

According to the engine start battery protection control device according to the embodiment of the present disclosure described above, the control ECU 71 can appropriately protect the engine start battery from over-discharge by limiting the supply of electricity to the starter motor 3 when the battery voltage when the engine switch 21 is on falls below a first predetermined value. This allows the control ECU 71 to suppress deterioration of the battery pack 61 (battery cells 611) and also suppress the operation of the protection circuit 711.

In addition, according to the protection control device for the engine starting battery according to the embodiment of the present disclosure, when the battery voltage when the engine switch 21 is on falls below a second predetermined value that is smaller than the first predetermined value, the control ECU 71 can appropriately protect the battery pack 61 (battery cells 611) from over-discharge by limiting discharge from the input/output terminal via the control ECU 71.

In addition, according to the protection control device for the engine starting battery according to the embodiment of the present disclosure, when the battery voltage when the engine switch 21 is on falls below a third predetermined value that is smaller than the second predetermined value, the control ECU 71 electrically disconnects the battery pack 61 from the control ECU 71, thereby appropriately protecting the battery pack 61 from over-discharge.

In addition, according to the protection control device for the engine starting battery according to the embodiment of the present disclosure, when the temperature rise rate of the battery cell 611 exceeds a predetermined temperature rise rate, the control ECU 71 restricts the input and output via the control ECU 71, thereby preventing accidents such as fire caused by abnormal heat generation in the battery cell 611.

The present invention is not limited to the above-described embodiments, but also includes variations of the above-described embodiments and appropriate combinations of these embodiments.

The contents described in each of the above embodiments can be understood, for example, as follows:

The protection and control device for an engine starting battery (battery pack) according to the aspect of [1] comprises:
A protection and control device for an engine starting battery (battery pack 61) that serves as a power source for a starter motor (3) that cranks an engine (1),
A control ECU (71) for controlling charging and discharging of one or more battery cells (611) constituting the engine starting battery (battery pack 61);
a protection circuit (711) for protecting the one or more battery cells (611) from overcharging and over-discharging;
Equipped with
The control ECU (71) limits the supply of electricity to the starter motor (3) when the battery voltage when the engine switch (21) is on falls below a predetermined first predetermined value.

According to the protection control device for the engine starting battery (battery pack 61) disclosed herein, the control ECU (71) can appropriately protect the engine starting battery (battery pack) from over-discharge by limiting the supply of electricity to the starter motor (3) when the battery voltage falls below a first predetermined value when the engine switch (21) is on.

[2] A protection control device for an engine starting battery (battery pack 61) according to another aspect is a protection control device for an engine starting battery (battery pack 61) according to [1],
The control ECU (71) limits discharge from the input/output terminal via the control ECU (71) when the battery voltage when the engine switch (21) is on falls below a second predetermined value that is smaller than the first predetermined value.

With this configuration, when the battery voltage when the engine switch (21) is on falls below a second predetermined value that is smaller than the first predetermined value, the control ECU (71) limits the discharge from the input/output terminal via the control ECU (71), thereby appropriately protecting the engine starting battery (battery pack 61) from over-discharge.

[3] A protection control device for an engine starting battery (battery pack 61) according to yet another aspect is a protection control device for an engine starting battery (battery pack 61) according to [2],
The control ECU (71) electrically disconnects the one or more battery cells (611) from the control ECU (71) when the battery voltage when the engine switch (21) is on falls below a third predetermined value that is smaller than the second predetermined value.

According to this configuration, when the battery voltage when the engine switch (21) is on falls below a third predetermined value that is smaller than the second predetermined value, the control ECU (71) electrically disconnects one or more battery cells (611) from the control ECU (71), thereby appropriately protecting one or more battery cells (611) from over-discharge.

[4] A protection control device for an engine starting battery (battery pack 61) according to yet another aspect is a protection control device for an engine starting battery (battery pack 61) according to any one of [1] to [3],
The control ECU (71) limits input/output passing through the control ECU (71) when a temperature rise rate of the battery cell (611) exceeds a predetermined temperature rise rate.

According to this configuration, when the temperature rise rate of the battery cell (611) exceeds a predetermined temperature rise rate, the control ECU (71) limits the input/output via the control ECU (71), thereby preventing accidents such as fires caused by abnormal heat generation in the battery cell (611).

LIST OF REFERENCE NUMERALS 1 Engine 12 Recoil starter 121 Starter grip 13 Charge coil 14 Regulator 15 Ignition coil 16 Spark plug 21 Engine switch 22 Engine start operation switch 23 Switch for external device 231 Choke changeover switch 24 Wiring coupler 25 Control harness 251 Engine charging input line 252 Engine switch operation detection line 253 Engine start operation detection line 254 Starter motor relay control line 255 Valve device output line 256 Battery voltage constant application line 3 Starter motor 4 Starter motor relay 41 Contact 5 External device 51 Valve control unit 52 Choke valve 6 Battery unit 6a Protrusion 6b Cushioning material 61 Battery pack 611 Battery cell 62 Housing 62a Protrusion 63 Wiring coupler 64 Starter motor power supply terminal 641 Power line (first power line)
642 Fuse 65 Battery protection relay 66 External charging input terminal 67 Charging output terminal 671 USB output terminal 68 Indicator 69 Charge remaining amount check button 7 Starting control device 71 Control ECU
711 Protection circuit 712 Engine charging input terminal 713 Power supply detection terminal 714 Engine start operation detection terminal 715 Starter motor relay control terminal 716 External device output terminal 717 Constant voltage output terminal 8 Case 9 Covers 9a, 9b Window 91 Bolt

Claims (3)

A protection and control device for an engine starting battery that serves as a power source for a starter motor that cranks an engine,
A control ECU that controls charging and discharging of one or more battery cells that constitute the engine start battery;
a protection circuit for protecting the one or more battery cells from overcharging and over-discharging;
Equipped with
When an engine switch is turned on, the control ECU switches from a standby state to a start state, and then compares a battery voltage with a first predetermined value. If the battery voltage when the engine switch is turned on falls below the first predetermined value, the control ECU limits the supply of electricity to the starter motor.
the control ECU limits discharge from an input/output terminal via the control ECU when a battery voltage at the time when the engine switch is turned on falls below a second predetermined value that is lower than the first predetermined value;
the control ECU electrically disconnects the one or more battery cells from the control ECU when a battery voltage at the time when the engine switch is turned on falls below a third predetermined value that is lower than the second predetermined value;
Even if the control ECU is electrically disconnected from the one or more battery cells, when electricity generated by a charge coil of the engine is supplied to the control ECU, or when electricity is supplied to the control ECU from an external power source, the control ECU releases the electrical disconnection between the one or more battery cells and the control ECU and starts charging the one or more battery cells .
Protection control device for engine starting battery. The control ECU limits input/output via the control ECU when a temperature rise rate of the battery cell exceeds a predetermined temperature rise rate.
The protection and control device for an engine starting battery according to claim 1 . When the supply of electricity is cut off before the battery voltage of the one or more battery cells recovers to the third predetermined value, the control ECU again electrically cuts off the one or more battery cells and the control ECU.
3. The protection and control device for an engine starting battery according to claim 1 or 2 .

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