JPH06295747A - Safety device - Google Patents

Abstract

PURPOSE:To prevent the occurrence of a pole change phenomenon and protect a device or a battery system by detecting voltage and the dispersion thereof regarding cells constituting the battery system and outputting a signal for controlling the operation of a device using the battery system, when the detected voltage and dispersion exceeds the prescribed value. CONSTITUTION:A safety circuit 2 first performs the sampling of the voltage values V1 to Vn of respective cells with detectors 3 under control by MCU 7. Thereafter, the maximum value Vmax and the minimum value Vmin of each voltage value are detected with a comparison means 4, and a difference between the maximum value Vmax and the minimum value Vmin is compared with the prescribed voltage value Vt. If (Vmax-Vmin)>Vt, dispersion is judged to exist, and a drive stop command D7 is issued via the MCU 7. In other cases, dispersion is judged not to exist, and a detection command D5 for the whole voltage Vall of a battery system l is issued to a comparison means 6 via the MCU 7. Then, the means 6 compares the voltage Veil with discharge stopping voltage Vlow, and if Vall<=Vlow, the command D7 is issued via the MCU 7. The drive of a device is continued in other cases.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device using an assembled battery as an internal power source, for example, a safety device such as a printer.

[0002]

2. Description of the Related Art Conventionally, in an apparatus, such as a printer, which uses an assembled battery composed of a plurality of single cell batteries as an internal power source, a safety circuit system as shown in FIG. By detecting the voltage of the entire battery, it is determined whether or not the capacity of the battery pack is sufficient to drive the device. In the figure, 1 is an assembled battery composed of a plurality of single cell batteries, 2 is a safety circuit system for the assembled battery 1, 5 is a total voltage V _all detector of the assembled battery 1, and 6 is a means for observing / comparing the capacity of the assembled battery 1. , 7 indicates the safety circuit control unit (MCU), and 8 indicates the power supplied to the device.

The operation will be described below: (1) The MCU 7 issues a command D5 to the comparing means 6 to detect the capacity of the battery pack 1. (2) The detector 5 is the assembled battery 1
To detect the entire voltage of. (3) The detector 5 outputs the measurement result V _all D4 to the comparison means 7. (4) The comparison means 6 compares the discharge end voltage V _low with the total voltage V _all . (5) The comparison means 6 outputs the result signal D6 to the MCU 7
Return to. (6) From the result signal D6, the MCU 7 determines whether or not the capacity of the battery pack 1 is sufficient, and if the capacity has dropped below a predetermined value, it sends a drive stop command D7 for the device.
It was a system that performed such an operation sequence.

[0004]

However, in the conventional example as described above, only the total voltage V _{all of the} assembled battery 1 is observed, and the single cell batteries constituting the assembled battery 1 are not observed. When the voltage capacity varied, it could not be detected.

In the case of such an assembled battery, when the above-mentioned abnormality occurs, a current flows from the high-capacity single-cell battery among the single-cell batteries constituting the assembled battery 1 to the low-capacity single-cell battery side. There is a possibility of causing a so-called "polarization" phenomenon that flows into the device. This may shorten the life of the battery pack or adversely affect the operation of the device. It is an object of the present invention to provide a safety device for protecting the device and the assembled battery from the problems peculiar to the assembled battery as described above.

[0006]

Therefore, in the present invention, this type of safety device detects the voltage of each single cell battery constituting the assembled battery in a device using the assembled battery as an internal power source. Detecting means, means for detecting a variation detection between voltage values of each single cell battery based on the detection output, and operation of the device when the variation between each voltage value of each single cell battery exceeds a predetermined value. Configured to have a signal output means for outputting a signal for controlling, or, in the device using the assembled battery as an internal power source, a detection means for detecting the voltage of each single cell battery constituting the assembled battery, Detecting means for detecting a variation between the voltage values of the single cell batteries based on the detection output, and a solution for eliminating the variation when the variation between the voltage values of the single cell batteries exceeds a predetermined value. By configured with bets, it is intended to achieve the object.

[0007]

With the configuration of the present invention as described above, the safety protection of the device and the assembled battery can be performed even when the capacities of the unit cell batteries forming the assembled battery vary.

[0008]

EXAMPLES The present invention will be described below based on examples.
FIG. 1 is a block diagram showing the construction of an embodiment of a printer safety device according to the present invention. The same (corresponding) constituent elements as those in FIG. Reference numeral 1 is an assembled battery in which n cell batteries are connected in series, 2 is a system of a safety circuit thereof, and 8 is electric power supplied to the device by the assembled battery 1.

Further, as a constituent element of the safety circuit 2, 3 is an n number of detectors for observing / detecting the voltages V _{1 to} V _n of the individual cell batteries constituting the assembled battery 1, and 4 is each voltage V. _{1 to} V
Comparing means for analyzing the variation between _n , 5 is a detector for observing / detecting the assembled battery 1 overall voltage V _all , 6
Is a comparison means for analyzing the total voltage value V _all , and 7 is
It is a safety circuit control unit (MCU) for managing the operation of the entire system.

Next, various data in this system will be described. D1 is a voltage value V _{1 to} V _{n of} each single cell battery constituting the assembled battery 1, D2 is a command (signal) for the MCU 7 to control the comparison means 4, and D3 is each obtained by the analysis result of the comparison means 4. Data indicating whether or not there is a variation between the voltage values V _{1 to} V _n (D1), D4 is a battery pack overall voltage value V _all observed by the detector 5, and D5 is a means for comparing the capacity detection of the battery pack 1 by the MCU 7. 6 is a command (signal) to be executed, D6 is analysis result data of the comparison means 6, and D7 is device control data input / output by the MCU 7. FIG. 2 is a flow chart showing the characteristic operation sequence of FIG. 1 of the present embodiment.

First, in step S11, the MCU 7 determines whether or not to analyze the variations of the voltages V _{1 to} V _n , and when the analysis is performed, the instruction (signal) D2 is sent to the comparing means 4. At this time, when the device is driven by the external power supply and the battery pack 1 is not used, this variation analysis is not performed (step S11 → end).

This variation analysis is performed in the following procedure; that is, in step S12, the detector 3 samples the voltage values V _{1 to} V _n (D1) of the single cell batteries. First, in step S13, the comparing means 4 is caused to detect the maximum value V _max in each voltage value data D1, and then in step S14, the comparing means 4 is caused to detect the minimum value V _min in each voltage value data D1. . Comparison means 4 calculates the V _max -V _min in step S15, it compares this value with a predetermined voltage value V _t.

At this time, if (V _max -V _min )> V _t (No), the comparison means 4 determines in step S16 the assembled battery 1
The data D3 is set with information indicating that there are variations in the individual cell batteries that make up the device, is notified to the MCU 7, and then M
The CU 7 transmits a drive stop command (signal) D7 for the device. On the other hand, in step S15, (V _max −V _min ) ≦
In the case of V _t (Yes), the comparison means 4 performs step S1.
In step 7, information indicating that there is no variation in each single cell battery that constitutes the assembled battery 1 is set and notified to the MCU 7,
The MCU 7 issues a command (signal) D5 to the comparison means 6 so as to detect the overall battery pack voltage V _all .

The detection of the total voltage V _all of the assembled battery is performed in the same manner as the conventional method. That is, in step S18, the detector 5 is caused to sample the total voltage V _all of the assembled battery 1, and then in step S19, the comparison means 6 is caused to compare the total voltage V _all with the discharge end voltage V _low . At this time, when V _all ≦ V _low (Yes), the comparison unit 6 notifies the MCU 7 that the battery capacity is low (data D6) in step S110, and the MCU 7 drives the device in step S112. Send a stop command (signal) D7. On the other hand, in step S19, if V _all > V _low (No), the MCU 7 determines in step S111 that the drive of the device can be continued,
The state of the safety circuit system returns to the state of step S11 again. After that, the MCU 7 repeats the same flow when it is necessary to continue the variation analysis.

In the above system, M
By equipping the CU 7 with a backup power supply, it becomes possible to promptly deal with a sudden trouble of the battery pack 1 such as a short circuit inside the battery pack 1. Further, the same system can be utilized for a multi-series and multi-parallel assembled battery by detecting the voltage value of each single cell battery.

By using the system of the present embodiment as described above, it is possible to check the state of the single cell battery constituting the assembled battery, and protect the device and the assembled battery.

(Other Embodiments) Next, other embodiments according to the present invention will be described. FIG. 3 is a view corresponding to FIG. 1 showing its configuration. In this embodiment, some components are added to the system of the embodiment shown in FIG. That is, 9 is a discharge circuit for eliminating a variation in voltage when the single cell batteries constituting the assembled battery 1 have a voltage variation,
Reference numeral 10 is a selector for connecting a specific single cell battery having a voltage variation and the discharge circuit 9. Also, D8
Indicates data for the MCU 7 to control the selector 10.

FIG. 4 is a sequence flowchart showing the system operation of this embodiment, and the basic flow is as follows.
2 is exactly the same as that of FIG. 2 in the first embodiment, and steps S21 to S212 in FIG.
Corresponding to steps S112 to S112, the subroutine and the return operation by the newly added constituent elements shown in FIG. 5 are incorporated in the above flow. Each step S21 to S2
Overlapping description of 11 is omitted, and the details of the additional parts will be described below.

The present construction is characterized in that, when a variation in capacity occurs in each single cell battery that constitutes the battery pack 1, the system operates in a direction to eliminate the variation. Specifically, the comparison unit 4 detects the variation in the case of No in step S25, and the MCU 7 performs the following control operation after receiving the result data D3 in step S26 (hereinafter, referred to in FIG. 5). Move). That is, step SR1
At 7, the MCU 7 issues a device drive stop command D7, and then the MCU 7 initializes the variation elimination in steps SR2 and SR3. In this embodiment, the variation is sequentially eliminated from the single cell battery 1 (with a voltage value V ₁ → i = 1). That is, step S
After R4, the detector 3 is made to sample the voltage value V _i at step SR5, and then the comparison means 4 is made to compare V _i and V _min (the minimum value among the voltage values V _{1 to} V _n ) at step SR6. Let

If V _i = V _min (No) in step SR6, the MCU 7 causes the variation of the next battery i + 1 to be eliminated, and the process returns to step SR3. On the other hand, V _i > V _min (Y
In the case of es), the MCU 7 issues a command D8 to connect the battery i and the discharge circuit 9 to the selector 10 in step SR7 to cause the battery i to be discharged. This discharge is V _i = V
It is continued until it becomes _min, and steps SR5 to SR7 are repeated. When the elimination of the variations in the capacities of all the cell batteries is completed (Yes in step SR4), the MCU 7 transmits the device drive restart command signal D7 in step SR8.
After this, the state of this safety circuit system returns to step S211 in the original flow of FIG.

As described above, when the capacity of each single cell battery constituting the battery pack 1 is varied, the discharge circuit 9 operates again so that the internal balance of the battery pack 1 is maintained. It is possible to protect both of the assembled batteries.

[0022]

As described above, according to the present invention,
It became possible to protect the device and the assembled battery by avoiding the capacity imbalance of each single cell battery that constitutes the assembled battery by the safety circuit.

[Brief description of drawings]

FIG. 1 is a configuration block diagram of an embodiment.

FIG. 2 is an operation sequence flowchart of FIG.

FIG. 3 is a configuration block diagram of another embodiment.

FIG. 4 is an operation sequence flowchart of FIG.

FIG. 5 is a flowchart of the additional operation sequence of FIG.

FIG. 6 is a configuration block diagram of an example of a conventional safety circuit.

[Explanation of symbols]

 1 assembled battery 2 safety circuit for assembled battery 3 voltage value detector for each single cell battery 4 comparison means for variation analysis of each single cell battery 5 overall voltage detector for assembled battery 6 comparison means for capacity observation of assembled battery 7 assembled battery Safety circuit control unit (MCU) 8 Supply power to the device 9 Discharge circuit (variation eliminating means) 10 Selector (variation eliminating means)

Front page continuation (72) Inventor Tetsuto Ikeda 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Yuichi Kaneko 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Junichi Arakawa 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (2)

[Claims] 1. In an apparatus using an assembled battery as an internal power source, between a detection means for detecting the voltage of each single cell battery constituting the assembled battery and each voltage value of each single cell battery based on this detection output. Safety characterized by having means for detecting variation detection and signal output means for outputting a signal for controlling the operation of the device when the variation between voltage values of each single cell battery exceeds a predetermined value apparatus. 2. In an apparatus using an assembled battery as an internal power source, between a detection means for detecting the voltage of each single cell battery constituting the assembled battery and each voltage value of each single cell battery based on this detection output. A safety device comprising: a detecting unit that detects a variation and a canceling unit that eliminates the variation when the variation between the voltage values of the single cell batteries exceeds a predetermined value.