Impact Detection System

Abstract

To avoid the increase in the number of parts and simplify the vehicle configuration when a shock detection system is designed to be installed in a vehicle with a detachable battery pack.SOLUTION: A vehicle (12) is detachably provided with a battery pack 10 including acceleration sensors 72a to 72c. The vehicle inputs and outputs electric power to and from the battery pack 10. In the vehicle, a shock detection system 70 is constituted of the acceleration sensors 72a to 72c and a control unit (74) that receive input signals from the acceleration sensors 72a to 72c, and controls power input / output between the vehicle and the battery pack 10. When a value of each input signal is equal to or greater than a predetermined value, the control unit performs control to stop input / output of electric power between the battery pack 10 and the vehicle.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to an impact detection system for a vehicle that inputs and outputs electric power to and from a detachable battery pack. [Background technology]

[0002] The acceleration sensor not only makes it possible to measure the degree of inclination with respect to the direction of gravity, but also makes it possible to detect the occurrence of vibration or impact. Utilizing this point, Patent Document 1 proposes configuring a vehicle anti-theft device including an acceleration sensor (referred to as an "inclination sensor" in Patent Document 1). In the technology described in Patent Document 1, the inclination sensor is provided in a position on the center console of a four-wheeled vehicle, close to the rear seat.

[0003] In this case, the inclination sensor has two detection elements, and the inclination in the longitudinal direction or width direction of the vehicle is always detected by the two detection elements, thereby improving the detection accuracy. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2007-147493 A (see especially paragraph

[0060] ) Summary of the Invention [Problem to be solved by the invention]

[0005] When attempting to configure an impact detection system including an acceleration sensor in a vehicle equipped with a detachable battery pack, it is expected that the number of acceleration sensors and peripheral devices will increase, making the vehicle configuration more complex.

[0006] The present invention has been made to solve the above-mentioned problems, and has an object to provide an impact detection system that can avoid an increase in the number of parts and simplify the vehicle configuration. [Means for solving the problem]

[0007] In order to achieve the above object, according to one embodiment of the present invention, there is provided an impact detection system for a vehicle, in which a battery pack including an acceleration sensor is detachably positioned and fixed by a positioning mechanism, and power is input / output between the battery pack and the battery pack, the impact detection system comprising: a control unit that receives an input signal from the acceleration sensor and controls input and output of electric power between the vehicle and the battery pack; The control unit performs control to stop input and output of electric power between the battery pack and the vehicle when the value of the input signal is equal to or greater than a preset predetermined value.

[0008] In addition, in the present invention, "stopping the input / output of electric power" includes not only switching from a state in which electric power input / output is being performed to a state in which it is stopped, but also not starting the input / output of electric power (maintaining the stopped state). Effect of the Invention

[0009] According to the present invention, the acceleration sensor provided in the battery pack is used to obtain information on the vehicle's inclination, vibration, etc. as an input signal. Therefore, there is no need to provide an acceleration sensor on the vehicle side. This makes it possible to avoid an increase in the number of vehicle parts. In addition, the vehicle configuration can be simplified accordingly. [Brief description of the drawings]

[0010] [Figure 1] 1 is a schematic left side view of a vehicle (electric motorcycle) provided with an impact detection system according to an embodiment of the present invention. [Diagram 2]2 is a schematic perspective view of a main portion showing a state in which a battery pack is housed in a resin case portion provided in the vehicle of FIG. 1 and an operating lever is in a non-removal position. [Diagram 3] 3 is a schematic perspective view of the essential parts showing a state in which the operating lever from FIG. 2 is set to a removal enabling position. FIG. [Figure 4] FIG. 2 is a schematic overall perspective view of the battery pack. [Diagram 5] FIG. 2 is a schematic circuit diagram showing a circuit inside the battery pack. [Figure 6] 4 is a schematic explanatory diagram illustrating a detection axis of an acceleration sensor provided in the battery pack. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A shock detection system according to a preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings. Note that the shock detection system is provided in a battery pack.

[0012] 1 is a schematic left side view of an electric motorcycle 12 that runs on power supplied from a battery pack 10. This electric motorcycle 12 is a scooter-type vehicle that has a step floor on which a rider seated on a seat 14 can place his or her feet.

[0013] The electric two-wheeler 12 has a front wheel 16 which is a steering wheel, and a rear wheel 18 which is a drive wheel. The front wheel 16 is rotatably supported by a pair of left and right front forks 20. A bar handle 22 is provided on the front forks 20, and the front wheel 16 is steered by a rider seated on the seat 14 operating the bar handle 22. As shown by an imaginary line in FIG. 1, the seat 14 can be rotated around its front end as a fulcrum until it assumes an upright position with its rear end extending upward. In addition, a power drive unit (PDU) 24 is provided near the step floor.

[0014] An electric motor 30 for driving the rear wheel 18 is mounted on the swing arm 26 that supports the rear wheel 18. In addition, resin case parts 32F, 32R shown in Figs. 2 and 3 are provided below the seat 14. The battery pack 10 is detachably housed in each of these resin case parts 32F, 32R (note that the battery pack 10 in the resin case part 32R is omitted in Figs. 2 and 3). Electric power is input and output between both battery packs 10 and the electric motor 30.

[0015] The resin case parts 32F, 32R are supported by a battery support frame 35 attached to the left and right rear frames 34 so as to be arranged side by side in the front and rear. Each of the resin case parts 32F, 32R has an insertion / removal opening 36 that opens upward, and is inclined so that the insertion / removal opening 36 faces diagonally upward toward the rear of the vehicle body. Therefore, when inserting or removing the battery pack 10, the battery pack 10 can be slid obliquely along the rear inner wall of the resin case parts 32F, 32R. Therefore, the battery pack 10 is mounted on the electric motorcycle 12 in an inclined state in the same posture as the resin case parts 32F, 32R.

[0016] Therefore, part of the weight of the battery pack 10 is supported by the rear inner walls of the resin case parts 32F, 32R. In this state, the battery pack 10 is positioned and fixed to the resin case parts 32F, 32R and the battery support frame 35 by a lock mechanism 40 (positioning mechanism) shown in Fig. 2. At the same time as this positioning and fixing, vehicle side terminals (not shown) provided on the resin case parts 32F, 32R engage with battery side terminals (not shown) of the battery pack 10. That is, both terminals are electrically connected.

[0017] The operation of switching the lock mechanism 40 between the battery fixed state and the battery unfixed state, and switching the battery side terminal and the vehicle side terminal between the connected state and the disconnected state, is performed via the operation lever 44. That is, one lock mechanism 40 includes two movable blocks 46. When the operation lever 44 is in the non-removal position shown in FIG. 2, the movable block 46 abuts against the upper surface of the battery pack 10, thereby restricting the displacement of the battery pack 10 in the removal direction. In addition, a rubber material having an uneven surface is provided on the contact surface of the movable block 46 and the battery pack 10. When these rubber materials come into contact with each other, friction resistance is generated, so that when the movable block 46 abuts against the battery pack 10, that is, when a pressing force is applied to the battery pack 10 from the removal direction, the displacement of the battery pack 10 in the front-rear and left-right directions is restricted. When the operation lever 44 is in the non-removal position shown in FIG. 2, the vehicle side terminals are raised inside the resin case parts 32F and 32R and engaged with the battery side terminals.

[0018] On the other hand, when the operating lever 44 is rotated to the removal position shown in FIG. 3, the two movable blocks 46 receive an operating force from the operating lever 44 and rotate so as to move away from each other. As a result, the two movable blocks 46 are in a retracted position where they do not interfere with the battery pack 10. At the same time, the vehicle side terminals are lowered in the resin case parts 32F, 32R and are separated from the battery side terminals. Therefore, the battery pack 10 can be removed from the resin case parts 32F, 32R through the insertion / removal opening 36. In this way, the battery pack 10 is detachable from the electric motorcycle 12. Although two operating levers 44 are provided, the remaining one may be rotated synchronously by rotating one of them.

[0019] The battery packs 10 are housed inside the resin case portions 32F, 32R and are arranged side by side in the front-rear direction of the electric motorcycle 12. The battery packs 10 will be described.

[0020] 4 is a schematic overall perspective view of the battery pack 10. The battery pack 10 includes a casing 56 including a bottom cover 50, a long casing body 52, and a top cover 54. The casing body 52 is a hollow body having a generally rectangular tubular shape with openings at both ends in the longitudinal direction (height direction), i.e., the lower end and the upper end in FIG. 1. The bottom cover 50 closes the opening at the lower end of the casing body 52, and the top cover 54 closes the opening at the upper end. The casing 56 thus configured has a generally rectangular prism shape.

[0021] The bottom cover 50 is provided with the battery side terminals. An arch-shaped portion 58 and a tab-shaped portion 60 protrude from opposing ends on the upper surface of the top cover 54. A handle 62 is bridged from the apex of the arch-shaped portion 58 to the apex of the tab-shaped portion 60. A user (e.g., a driver) can easily lift or carry the battery pack 10 by gripping the handle 62. When the battery pack 10 is housed inside the resin case portions 32F, 32R, the battery pack 10 is in a position where the bottom cover 50 faces downward and the top cover 54 faces upward.

[0022] A cell holder that holds a number of battery cells is housed within the casing 56. The battery cells are, for example, lithium secondary batteries, and after their capacity (amount of stored electricity) is reduced by supplying power to an external load, the capacity can be restored by receiving power from a charging device. In other words, the battery cells can be repeatedly charged and discharged. Since this configuration is well known, the cell holder and battery cells are not specifically shown.

[0023] 5, an impact detection system 70 according to this embodiment is further housed within the casing 56. The impact detection system 70 includes a plurality of (e.g., three) acceleration sensors 72a to 72c, a battery management unit 74 as a control unit, and the like. In the following, the battery management unit may be abbreviated as "BMU."

[0024] The acceleration sensor 72a is a so-called three-axis sensor having three detection axes 76aa to 76ac. As shown in Fig. 6, when the battery pack 10 is placed on a horizontal plane H, the three detection axes 76aa to 76ac of the acceleration sensor 72a are inclined with respect to the horizontal plane H and the vertical direction G. For example, the detection axis 76aa has a predetermined azimuth angle or elevation angle (or depression angle) with respect to the vertical direction G. The detection axis 76ab has a predetermined azimuth angle with respect to the vehicle width direction, and the detection axis 76ac has a predetermined azimuth angle with respect to the vehicle length direction. The detection axes 76ab and 76ac may further have a predetermined elevation angle (or depression angle) with respect to the horizontal plane H.

[0025] The acceleration sensors 72b and 72c are also three-axis sensors like the acceleration sensor 72a. However, the degree and direction of inclination of the detection axes 76ba-76bc of the acceleration sensor 72b differ from the degree and direction of inclination of the detection axes 76aa-76ac of the acceleration sensor 72a. Furthermore, the degree and direction of inclination of the detection axes 76ca-76cc of the acceleration sensor 72c differ from the degree and direction of inclination of the detection axes 76aa-76ac of the acceleration sensor 72a, and also differ from the degree and direction of inclination of the detection axes 76ba-76bc of the acceleration sensor 72b.

[0026] The acceleration sensors 72a to 72c respectively detect the inclination of the electric motorcycle 12 in the vehicle height direction, vehicle width direction, and vehicle length direction. Furthermore, when the electric motorcycle 12 vibrates or receives an impact, they detect the vibration or impact. The acceleration sensors 72a to 72c transmit information relating to such inclination, vibration, and impact, indicating the extent of the inclination, vibration, and impact in the vehicle height direction, vehicle width direction, and vehicle length direction, to the BMU 74 as an information signal.

[0027] The BMU 74 performs cell management and receives information signals related to the voltage and temperature inside the battery pack 10. The BMU 74 controls the operation of the battery pack 10 based on such various information. That is, for example, the BMU 74 controls the input and output of electric power between the battery pack 10 and the electric motorcycle 12 (PDU 24). Here, the input and output of electric power includes the transfer of electric energy and the transfer of communication signals.

[0028] In this embodiment, two battery packs 10 are simultaneously mounted on the electric motorcycle 12. Therefore, each electric motorcycle 12 is equipped with two of each of the acceleration sensors 72a to 72c.

[0029] In this embodiment, an acceleration sensor is not provided in the electric motorcycle 12. Therefore, the PDU 24 receives information via the BMU 74 regarding the degree to which the electric motorcycle 12 is tilted, the degree of vibration and impact applied to the electric motorcycle 12, and the like.

[0030] The impact detection system 70 according to this embodiment is basically configured as described above, and its effects will be described below. Note that the user in the following description is typically the driver of the electric motorcycle 12, but may also be an operator who replaces the battery pack 10.

[0031] When replacing the battery pack 10 with a fully charged one, the user of the electric motorcycle 12 rotates the seat 14 so that the front end is the center of rotation and the rear end faces vertically upward (see the imaginary line in Fig. 1). This exposes the insertion / removal port 36 as shown in Fig. 3, and enables the user to visually check the battery packs 10 in the resin case portions 32F, 32R from above the electric motorcycle 12.

[0032] Next, the user grasps the operating lever 44 and pulls it forward, that is, down to the removal position shown in FIG. 3. As a result, the two movable blocks 46 move to a retracted position where they do not interfere with the battery pack 10, and the locking mechanism 40 is released. Also, the vehicle side terminals move down and are separated from the battery side terminals. As a result, the battery pack 10 is released from being restrained by the electric motorcycle 12. The user simply grasps the handle 62 of the battery pack 10 and pulls it upward. This causes the battery pack 10 to be pulled out of the resin case portions 32F, 32R. That is, the battery pack 10 is detached from the electric motorcycle 12.

[0033] Next, the user inserts the two fully charged battery packs 10 into the resin case portions 32F, 32R, respectively. At this time, the user just needs to grasp the handle 62 to lift the battery pack 10, pass it through the insertion / removal opening 36, and slide it obliquely along the rear inner wall of the resin case portions 32F, 32R. Thus, the battery pack 10 is inserted into the resin case portions 32F, 32R with the bottom cover 50 facing downward and the top cover 54 facing upward.

[0034] However, after the user lifts the battery pack 10, an unexpected event may occur that causes the battery pack 10 to drop. The acceleration sensors 72a to 72c acquire the acceleration during this drop and the degree of impact when the battery pack 10 hits the ground as input signals, and transmit them as information signals to the BMU 74. The BMU 74 stores the acceleration and the degree of impact as numerical values.

[0035] As described above, the detection axes 76aa-76ac, 76ba-76bc, and 76ca-76cc of the acceleration sensors 72a-72c are inclined with respect to the horizontal plane H and the vertical direction G. This makes it easy to detect that the battery pack 10 has been dropped. In addition, the degree of acceleration and impact during the drop can be precisely quantified.

[0036] The two battery packs 10 that have reached the bottom walls of the resin case parts 32F, 32R are inclined with respect to the vertical direction G (vehicle height direction) along the inclination of the resin case parts 32F, 32R. At this time, all of the detection axes 76aa-76ac, 76ba-76bc, and 76ca-76cc of the acceleration sensors 72a-72c in the battery packs 10 are inclined with respect to the vehicle height direction, the vehicle width direction, and the vehicle length direction.

[0037] Next, the user grasps the operating lever 44 and pulls it backward, that is, to the non-removal position shown in FIG. 2. As a result, the two movable blocks 46 reach an interference position where they cover the battery pack 10, and the locking mechanism 40 locks the battery pack 10. The vehicle-side terminals also rise to engage (connect) with the battery-side terminals. As a result, the battery pack 10 is restrained to the electric motorcycle 12. This restraint firmly positions and fixes the battery pack 10 within the resin case portions 32F, 32R.

[0038] That is, the inclination angle of the battery pack 10 in the resin case parts 32F, 32R is restricted. Also, the battery pack 10 is restricted so as not to move in any of the vehicle height direction, vehicle width direction, and vehicle length direction. Therefore, the battery pack 10 is strictly prevented from inclining or vibrating in the resin case parts 32F, 32R. This prevents rattling of the battery pack 10 in the resin case parts 32F, 32R from being detected as inclination or vibration of the electric motorcycle 12.

[0039] Here, if the numerical values ​​(input signals) of the degree of acceleration or impact stored in the BMU 74 exceed a predetermined value set in advance due to a fall or the like, the BMU 74 judges that "power output from the battery pack 10 to the electric motorcycle 12 or in the reverse direction is not permitted." This makes it possible to avoid using a battery pack 10 that may have malfunctioned or been damaged due to a fall or the like.

[0040] When the numerical value of the degree of acceleration or impact falls below a predetermined value, the BMU 74 determines that "power output from the battery pack 10 to the electric motorcycle 12 or in the reverse direction is permitted." As a result, power is supplied from the battery pack 10 to the electric motor 30, and information signals are exchanged between the BMU 74 and the PDU 24.

[0041] When the electric motorcycle 12 starts traveling, the electric motorcycle 12 tilts depending on the road surface conditions. This tilt is constantly detected by the acceleration sensors 72a to 72c, and the information is sent as an information signal to the BMU 74. The BMU 74 further sends this information signal to the PDU 24. As described above, the battery pack 10 is strictly prevented from tilting relative to the vehicle body inside the resin case parts 32F, 32R, so the tilt of the electric motorcycle 12 can be detected with high accuracy.

[0042] It is assumed that an object may collide with the electric motorcycle 12 while the electric motorcycle 12 is traveling. In this case, the acceleration sensors 72a to 72c acquire the degree of vibration or impact applied to the electric motorcycle 12 in the vehicle height direction, vehicle width direction, and vehicle length direction as an input signal (numeric value). By quantifying the impact at multiple locations in this way, the accuracy of the information is improved. The BMU 74 then receives information related to this numerical value.

[0043] At this time, the numerical values ​​sent from the acceleration sensors 72a to 72c may differ from each other. Also, the numerical value sent from the battery pack 10 in the front resin case part 32F may differ from the numerical value sent from the battery pack 10 in the rear resin case part 32R. In such a case, the BMU 74 compares the numerical values ​​(input signals) obtained from the total of six acceleration sensors 72a to 72c and refers to the largest input signal. In this way, by adopting the maximum value from among the input signals of the multiple acceleration sensors 72a to 72c, it is possible to improve the detection accuracy.

[0044] Then, when the referenced maximum input signal is equal to or greater than a preset predetermined value, the BMU 74 stops the supply of power from the battery pack 10 to the electric motor 30. The BMU 74 also stops sending and receiving information signals between the BMU 74 and the PDU 24. In other words, the input and output of power between the battery pack 10 and the electric motorcycle 12 is stopped, and the battery pack 10 is electrically insulated from the electric motorcycle 12. Therefore, for example, the electric motor 30 is stopped and the electric motorcycle 12 is stopped. This prevents leakage of electricity and the like.

[0045] In this embodiment, the acceleration sensors 72a to 72c and the BMU 74, which is a control unit, are provided on the battery pack 10 side. Therefore, the process from when an information signal of an input signal is input to the BMU 74 until the input and output of electric power is stopped, in other words, until the control is terminated, is carried out quickly. Of course, the electric motorcycle 12 also stops quickly.

[0046] In this way, by providing the acceleration sensors 72a-72c and the BMU 74 (control unit) on the battery pack 10 side, judgment and control by the BMU 74 can be performed quickly. Furthermore, since vibrations and impacts applied to the electric motorcycle 12 can be detected by the acceleration sensors 72a-72c provided on the battery pack 10, there is no need to provide a separate acceleration sensor on the electric motorcycle 12 side. Furthermore, since the BMU 74 is provided on the battery pack 10, there is no need to provide a separate control unit for acquiring information from the acceleration sensors 72a-72c on the electric motorcycle 12. For the above reasons, it is possible to avoid an increase in the number of parts when constructing the impact detection system 70. Furthermore, this can simplify the configuration of the electric motorcycle 12 accordingly.

[0047] Depending on the degree of the impact, it may be difficult for the ECM or the like to send accurate information to the BMU 74. Therefore, if input / output of electric power continues between the battery pack 10 and the electric motorcycle 12, there is a concern that the BMU 74 may erroneously control the battery pack 10 based on erroneous information, which may cause the electric motorcycle 12 to continue traveling. However, in this embodiment, the input / output of electric power is stopped as described above. This stops the electric motor 30, allowing the electric motorcycle 12 to stop spontaneously. In addition, for example, it is also possible to prevent leakage of electric power from the battery pack 10.

[0048] Instead of providing a control unit in the battery pack 10, a control unit may be provided in the electric motorcycle 12. In this case, for example, the PDU 24 can serve as the control unit. Even in this configuration, there is no need to provide the acceleration sensors 72a to 72c in the electric motorcycle 12, so it is possible to avoid an increase in the number of parts when constructing the impact detection system 70. Furthermore, the configuration of the electric motorcycle 12 can be simplified.

[0049] According to this configuration, the input and output of electric power between the battery pack 10 and the electric motorcycle 12 is determined on the electric motorcycle 12 side.

[0050] The present invention is not particularly limited to the above-described embodiment, and various modifications are possible without departing from the spirit and scope of the present invention.

[0051] For example, the inclinations of the detection axes 76aa-76ac, 76ba-76bc, and 76ca-76cc of the acceleration sensors 72a-72c may be made to match in the same battery pack 10. Even in this case, the BMU 74 or PDU 24 stops the input / output of electric power from the battery pack 10 to the electric motorcycle 12 in the same manner as described above when any of the information signals received from the total of six acceleration sensors 72a-72c is equal to or greater than a predetermined value.

[0052] Furthermore, the number of acceleration sensors is not limited to three, but may be one or two.

[0053] Furthermore, the vehicle to which the impact detection system 70 according to the present invention is applied is not limited to the electric motorcycle 12, but also includes saddle-type three-wheeled vehicles, four-wheeled vehicles, etc. In a vehicle provided with a passenger compartment (for example, a four-wheeled vehicle), it is preferable to activate an airbag when the impact detection system 70 detects an impact value equal to or greater than a predetermined value. [Explanation of symbols]

[0054] 10... Battery pack 12... Electric two-wheeler 14…Seat 24…Power drive unit 30: Electric motor 32F, 32R: Resin case 40...lock mechanism 44...operating lever 46... Movable block 50... Bottom cover 52...Casing body 54...Top cover 56…Casing 62…Handle 70...Impact detection system 72a to 72c...Acceleration sensor 74…Battery management unit 76aa~76ac, 76ba~76bc, 76ca~76cc...Detection axis

Claims

1. An impact detection system for a vehicle, in which a battery pack including a plurality of acceleration sensors is detachably positioned and fixed by a positioning mechanism, and power is input and output between the battery pack and the battery pack, the plurality of acceleration sensors detect inclination of the vehicle in a vehicle height direction, a vehicle width direction, and a vehicle length direction while the vehicle is traveling, and detect vibrations or impacts on the vehicle; a control unit that receives input signals related to vibration or impact in the vehicle acquired by the plurality of acceleration sensors and controls input / output of electric power between the vehicle and the battery pack; The control unit is provided in the battery pack, and is an impact detection system that performs control to stop the input and output of power between the battery pack and the vehicle when the value of the input signal is equal to or greater than a predetermined value set in advance.

2. 2. The impact detection system of claim 1, wherein the vehicle is provided with a separate control unit which communicates information signals with the control unit.

3. 3. The impact detection system according to claim 1, wherein when a maximum value among the input signals from the plurality of acceleration sensors is equal to or greater than the predetermined value, input / output of power between the battery pack and the vehicle is stopped.

4. 4. The impact detection system according to claim 3, wherein the inclinations of the detection axes of the plurality of acceleration sensors are different from each other.

5. 5. An impact detection system as claimed in claim 1, wherein when the battery pack is removed from the vehicle and placed on a horizontal surface, the detection axis of the acceleration sensor is inclined at a predetermined angle with respect to the horizontal plane and the vertical direction.

6. 6. The impact detection system according to claim 1, wherein the control unit obtains the input signal when the battery pack is attached to the vehicle.

7. An impact detection system as described in any one of claims 1 to 5, wherein the control unit acquires as the input signal an input signal that was input to and stored in the battery pack before the battery pack was attached to the vehicle.

8. 8. The impact detection system according to claim 7, wherein the control unit performs control so as not to input or output electric power between the battery pack and the vehicle when the battery pack is attached to the vehicle.

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