JPH041554B2 - - Google Patents

Description

[Detailed description of the invention]

<Industrial Application Field> The present invention relates to a power supply device, an accessory unit that can be detached from the power supply device, and a power supply system. <Prior Art> Conventionally, there are cameras in which, for example, a power source is provided inside the camera to drive, for example, an aperture built into a lens unit. However, in such a system, if the lens unit is configured to be detachable from the camera, the timing of power supply to the lens unit becomes important. In particular, if a microcomputer (hereinafter referred to as microcomputer) is built into the lens unit and camera, and an electric motor for driving the aperture is built into the lens, it will be fatal if the signal line of each microcomputer is shot. There is a risk of serious destruction. Furthermore, the amount of power supplied to the electric motor etc. is much larger than in a lens unit that only has a ROM or the like (for example, JP-A-59-46634). Therefore, the risk of destruction as described above is higher.
Also, of course, if you do not use the limited power supply inside the camera body efficiently, the power will quickly run out. On the other hand, it is conceivable to provide the above-mentioned system with a switch or the like that detects whether or not a lens is attached, and to control the power supply to the lens unit in accordance with the operation of this switch.
(For example, JP-A-58-83824) <Problems to be solved by the present invention> In the above-mentioned system, for example, even if the lens is not actually attached, the detection switch may be turned on intentionally or negligently. Sometimes. In that case, a large voltage will be applied to the power supply terminal to the lens side, and there is a high possibility that this terminal will come into contact with the communication terminal of the camera or the microcomputer on the lens side. And, if contact occurs, each microcomputer will suffer irreparable damage. Further, even if a lens is attached, if this lens is an inappropriate lens that cannot be controlled from the camera side, it is extremely wasteful to continue supplying power. In particular, it is impossible to predict what the microcomputer on the lens unit will do when a predetermined command is sent from the camera side to such an inappropriate lens unit, and in some cases, the aperture may be changed. There is also the possibility of making a mistake such as constantly supplying current to the motor used to drive it. In that case, there is a drawback that the power supply on the camera side is consumed within an extremely short period of time. The present invention aims to solve these drawbacks of the conventional technology, and makes it possible to effectively control the power supply timing between a general power supply device and other devices that can be attached to and detached from it. The object of the present invention is to provide a power supply device, an accessory unit detachable from the power supply device, and a power supply system. <Means for Solving the Problems> The power supply device of the present application has a detachable accessory unit having a drive system that converts electric power into mechanical energy, and is a power supply device that supplies electric power to the accessory unit. a power supply means that becomes capable of supplying power to the accessory unit after connection with the accessory unit; and after the power supply means becomes capable of supplying power to the unit;
A first signal is outputted to the accessory unit, and when a predetermined signal corresponding to the first signal is not detected, the power feeding means controls the drive system so that the drive system does not operate. and a control means for controlling the power supply. Further, the accessory unit of the present invention outputs a first signal after becoming ready for power supply, and prevents the drive system from operating when a predetermined signal corresponding to the first signal is not detected. and a control means for controlling power supply for the drive system, the accessory unit being detachable from the power supply device, the receiving means receiving power supply from the power supply device, the first signal being received from the power supply device, It is characterized by comprising means for transmitting the predetermined signal to the power supply device when transmitted, and the drive system for converting the electric power received by the receiving means into mechanical energy. Further, the power supply system of the present application includes a power supply means that can supply power to the accessory unit after connection with the accessory unit, and a first signal to the accessory unit after the power supply means becomes ready to supply power. control means for controlling power supply to the drive system by the power supply means so that the drive system in the accessory unit does not operate when a predetermined signal corresponding to the first signal is not detected; a power supply device comprising: a receiving means for receiving power supply from the power supply device;
means for transmitting the predetermined signal to the power supply device when the first signal is transmitted from the power supply device; and the drive system for converting the electric power received by the receiving means into mechanical energy; It is characterized by consisting of a power supply unit and a removable accessory unit. <Embodiment> FIG. 2 is a configuration example diagram of an electronic camera main body 100 as an example of a power supply device of the present invention, in which C1 is a main microcomputer, C2 is a main interface, C21,
C25 is the power output terminal, C22 and C26 are
DATA terminal, C23, C27 are BUSY terminal, C
24 and C28 are GND terminals. C3 is ROM,
C4 is the power supply section, C5 is the disk drive section, C6
is a photometry system, C7 is a rectangular measurement system, and SSW1 and SSW2 are safety switches as detection means. 200 is a lens unit as a first device, which is an electronic camera 1;
It can be attached to and detached from 00. L1 is the sub microcomputer, L2 is the lens side interface, L
21 is the power supply terminal, L22 is the DATA terminal, L23
is the BUSY terminal, L24 is the GND terminal, L3 is the
ROM, L4 is an aperture drive system, L5 is a focus drive system, and L6 is a zoom drive system. Also, 300 is a strobe unit as the first device, S1 is a sub microcomputer, S2 is a strobe side interface, S21 is a power supply terminal, S22 is a DATA terminal, S23 is a BUSY terminal,
S24 is a GND terminal, S3 is a ROM, and S4 is a strobe light emitting section. In order to explain the basic connection between the power supply device and the first device, an example in which a lens unit is used as the first device will be described below. Note that the present invention includes not only the camera body but also all general electronic equipment including a power source as a power supply device.
Further, the first device also includes all accessory electronic devices that can be attached to and detached from the electronic device. Further, the detection means is not limited to a mechanical switch, but may be any type of device such as an optical switch or a magnetic sensor. Next, FIG. 3 is a diagram showing an example of the main part configuration of the main interface circuit C2 of the power supply device of the present invention.
1 and Q2 are switching transistors. The transistor Q1 is provided in a power supply path from the power supply C4 to the lens side power supply terminal C21. The SSW is a safety switch that turns ON when the first device, the lens unit, is attached to the camera body. FIG. 4 is a diagram explaining this situation. For example, a screw 19' is cut at the end of the lens unit 200. By screwing this screw 19' into the screw 19 on the camera body side, the lens unit 200 can be attached to the camera body 100. It is configured so that it can be installed on the Further, when the screws 19' and 19 are completely screwed together, the end surface 18' of the lens unit 200 and the corresponding end surface 18 of the camera body are brought into pressure contact. At this time, the terminals T'21 to T'21 connected to the terminals L21 to L24 of the lens side interface L2, respectively.
T'24 and terminal C of main interface C2
Terminals T21 to T2 connected to 21 to C24, respectively
4 are in contact with each other, thereby C21 to C24
Connections between L21 and L24 are made. At this time, the elastic convex portion 16 provided on the lens unit falls into the concave portion 17 provided on the camera body, turning on the switch SSW1. Now, returning to FIG. 3, when the switch SSW1 is turned on, a current flows from the constant voltage Vcc through the resistor R1 and the diode 14, and the anode of the diode becomes low level. This low level is inverted by the inverter 15 and input to the main microcomputer C1. In response to this input, the main microcomputer C1 starts operating according to a program as described below. When a predetermined output signal is output from the main microcomputer C1, the switch 13 is turned on. In this way, the switch 13 is turned on only when both the safety switch SSW is turned on and the predetermined output from the main microcomputer is obtained. When switch 13 turns on, transistor Q2 turns on.
Turn on. By turning on this transistor Q2, Q
Current flows through resistor R2 connected between the emitter and base of Q1, turning Q1 ON. This allows power supply to the lens unit from the power supply C4 inside the camera. FIG. 5 is a diagram showing details of the circuit shown in the third diagram, in which Q3 to Q5 are transistors and D1 to D3 are diodes. When SSW is ON, no current flows to D2, so transistor Q5 is OFF. At this time, when the switch 13 is turned on by a signal from the main microcomputer C1, Q2 is turned on, and this current flows to the base of Q3, turning it on. Q4
is for stabilizing the operation of Q3. Q3
When Q1 turns on, power is supplied to the lens unit from the power supply C4 inside the camera. On the other hand, when switch SSW is OFF, current flows through D2 and Q5 is turned ON. At this time, Q1 becomes OFF regardless of whether the switch 13 is ON or OFF. Next, FIG. 6 is a flowchart showing the operation of the main microcomputer C1. First, in step #1, power is supplied to the main microcomputer C1. Next, it is determined in step #2 whether SSW is ON or not. This is done depending on whether the output of the inverter 15 is high or low. When SSW is OFF, switch 13 is turned OFF and Q1 is turned OFF. (Step #3) As a result, power is not supplied to the lens unit. SSW
If it is ON, switch 13 is turned ON in step #4. This turns Q1 ON and supplies power to the lens unit. After that, in step #5, the DATA line is set to low level. (Set as Break.) Also, maintain this state for about 1 msec, for example. As a result, the sub-microcomputer L1 is automatically reset. In step #6, DATA is set high again to start initializing the lens side, and wait in step #6 for a sufficient time to complete this initialization. Next, proceed to step #7 and clear the check count. (#17) Next, in step #18, open the main interface.
Set BUSY to high level. If the sub-microcomputer L1 of the lens unit is in the receiving state, the BUSY line becomes low level. Therefore, in step #19, it is determined whether the BUSY line is at a high level or not, and if it is at a high level, the check count is increased by one. (Step #22)
In this case, the check count starts from zero, so it becomes "1". Next, in step #23, it is determined whether the count value is less than 3, and if it is less than 3, the process returns to step #18 again.
Check the BUSY line. If the BUSY line is still at a high level even after repeating steps #18, #19, #22, and #23 three times in this way, the process moves from step #23 to step #10 and the switch 13 is turned OFF. After that, in step #11, it is determined whether or not the power of the main microcomputer C1 is turned off, and if it is turned off, the program is terminated. In this way, in this embodiment, the check operation is performed multiple times to check whether the state of the sub microcomputer is in an abnormal state such that it cannot receive data from the main microcomputer, thereby preventing errors in the check operation itself. We are trying to prevent this from happening. Therefore, the yield of main and sub microcomputers can be increased. Now, in step #19, the submicrocontroller side
When the BUSY line is ready for reception, that is, when BUSY is at a low level, the process advances to step #20, and the DATA line on the camera side is set to a low level. In this embodiment, the BUSY line on the receiving side is set to high level when data is sent from the main microcomputer for a predetermined period of time, so the BUSY line on the sub-microcomputer side should be at high level under normal conditions. Therefore, in step #21, it is determined whether the BUSY line on the lens side is high or not, and if it is low, the check count is increased again in steps #22 and #23. When checks #18 to #23 are repeated three times, steps #10 and #11
The process of moving to is as explained earlier. If the lens unit side
If it is determined that BUSY is high, it is considered that the BUSY line is not disconnected, so the process moves to step #8. In step #8, a command "TEST ID" is sent to the lens unit. This command allows the ID of the lens unit to be set as described later.
A code will be sent to you, so go to step #9.
Check ID code. If the ID code is not correct, the power to the sub-microcomputer will be turned off in step #10. If the ID code is correct, move on to step #12.
Check whether the main microcontroller is turned on. If the main microcomputer is not turned on, send a command to open the aperture of the lens unit in step #15. After that, move to step #16 and turn off the switch 13 to cut off the power supply to the lens side.
Also, if it is determined in step #12 that the main microcomputer is powered on, the process moves to step #13, where various commands are sent as described later. As a result, the state of each part within the lens unit is controlled in step #14. Steps #13 and #14 are continued until the main microcomputer is turned off. Next, Figure 7 is a flowchart showing the operation on the lens unit side.
When DATA becomes high level, the RAM in the sub microcontroller is cleared in step #24.
Also, each port on the lens side interface
Set the DATA terminal to high level and the BUSY terminal to low level. Next, in step #25, the diaphragm is initialized as described later to bring it into a predetermined open aperture state. As a result, when the aperture becomes open, an open switch OSW (not shown) is turned on. Next, in step #26, it is determined whether or not a command has been sent from the camera body, and if it has been sent, the process proceeds to step #27 and sends the command to the command interpreter. In step #28, the command interpreter determines whether this command is among those stored in ROML3, and if so, sends this command back to the camera body. (#29) At the same time, the routine jumps to a routine corresponding to the above command in step #30, executes this routine in step #31, and then returns to the command waiting state in step #26. Also, the command in step #28
If it is not stored in ROML3, a command error signal is sent to the camera body in step #32, and the command wait state is returned to in step #26. Next, Figure 8 shows step #8 in Figure 6.
This diagram shows the details of step #31 on the lens side for the command "TEST ID" for testing the ID. The process starts from step #30 in FIG. 7, and it is determined in step #33 whether or not there is a phase error. This is the main interface on the camera body side.
If the DATA end is low or the BUSY end is high, data cannot be sent from the lens side, so such DATA, BUSY
This step is to determine the level of each line. If there is no phase error, proceed to step #34 and send keyword code 1 to the camera body. Here, the keyword code is selected from, for example, an ASCII character string and is set to have a large number of repetitions of 0 and 1. Therefore, the amount of information is increased. This has the effect of improving self-clocking characteristics and making it easier to detect errors. Specifically, in this example, such a code is "0101 0011
0101 0010 0010 1010 0101 1010" is used. Among these, the first 1bite "0101 0011" is keyword 1, the next 1bite "0101 0010" is keyword 2, the next 1bite "0010 1010" is keyword 3, and the next 1bite "0101 1010" is keyword 4. As mentioned above, keyword code 1 is sent to the camera side in step #34, then it is determined whether there is a phase error in step #35, and if there is no phase error, keyword code 2 is sent in step #36. Thereafter, a phase error is detected in step #37, and if there is no error, keyword code 3 is sent in step #38. A phase error is detected in step #39, and if there is no error, keyword code 4 is sent in step #40. After that, a phase error is detected in step #41, and if there is no error, the manufacturer type code is sent in step #42. The manufacturer type code is
It consists of 4 bits, and the manufacturer code consists of a combination of 4 bits of 0 and 1. The type code is structured as shown in the table below.

[Table] After that, a phase error is detected in step #43, and if there is no error, a serial number code is sent. (Step #44) The serial number code consists of 1 bit and indicates the serial number of the lens unit. For example, it is used to distinguish between the old product series and the new product series when the product series is changed. After that, a phase error is detected in step #45, and if not, a 1-bit function code is sent in #46. The function code is constructed such that each bit indicates a characteristic of the lens unit. For example, the least significant bit is configured to indicate the presence or absence of AF, and the next bit indicates the presence or absence of microposition. Of course, the remaining bits can also contain various other information. Each phase error detection step #33, #35,
If an error is detected in #37, #39, #41, #43, or #45, or if the function code transmission ends in step #46, the process moves to a command wait routine in step #47. Therefore, #26 in Figure 7 until the next command comes.
The determination is made in the following steps. In the above embodiments, the ID code of the lens unit as the first device may not be appropriate.
Since power supply to the lens unit is stopped if predetermined conditions with the camera body are not met, unnecessary power consumption can be prevented. Furthermore, in this embodiment, an abnormality in the lens unit is detected by determining the status of the DATA line and BUSY line of the lens unit as the first device, so even if the lens unit breaks down, it can be detected immediately. In addition, since the power supply to the lens unit is cut off in such a case, it is possible to prevent electric leakage and the like. In addition, in this embodiment, all the necessary information can be read from the lens unit by just sending one command from the camera body in order to determine the ID code of the lens unit, so there is no need to read the information between the camera body and the lens unit. The time required to send and receive signals can be significantly reduced. Furthermore, more information can be sent and received within a limited time. Therefore, it is possible to precisely control the state of external devices such as the lens unit at high speed. Furthermore, in this embodiment, a common keyword code is provided for each interchangeable lens unit, and this code is read out by the first command from the camera body, so that the ID information can be read out most efficiently. You can also combine keyword codes into multiple units (e.g.
Each time the code of each unit is sent to the camera body, it is checked for phase errors with the camera, and the code is sent again from the beginning, so there is no misidentification of the code. Further, since phase errors are similarly detected for each unit for other ID codes, etc., the same effect can be obtained. In the example, after power is supplied to the lens unit, the status of both the DATA and BUSY lines on the lens unit side is checked, and if they are inappropriate, power is not supplied to the lens.
Since it is turned off, it has the effect of detecting abnormalities on the lens side in an extremely short time compared to systems that read keywords on the lens side and cut off the power supply to the lens if the keywords are inappropriate. Moreover, there is no need to worry about power being supplied to the lens unit by accident when the lens is not installed.In the worst case, if an inappropriate lens is attached and power is started to be supplied to the lens, the terminal arrangement on the lens side will cause the camera to Alternatively, there is a possibility that an erroneous large current may flow into the microcomputer on the lens side, but such a problem can be avoided by short-time determination as in this embodiment. In the embodiment described above, the power supply means that becomes ready to supply power to the accessory unit after connection with the accessory unit is set to the second power supply means that executes #2 and #3 in FIG. 6 according to the state of SSW1 in FIG. The main interface C2 shown in the figure is the main interface C2, and after the power supply is supplied by the power supply means, the first signals (in the embodiment, BUSY-H at #18, DATA-L at #20,
Alternatively, a predetermined signal corresponding to the first signal (corresponding to the TEST ID in #19 in the embodiment) is transmitted to the accessory unit.
BUSY=L or BUSY=H in #21,
or ID in #21) is not detected, the drive system in the accessory unit (in the example, the second
The main interface C2 that executes #10 in FIG. 2 is used as a control means for controlling power supply to the drive system by the power supply means so that L4, L5, L6) in the figure do not operate. Further, in the embodiment, the receiving means for receiving power supply from the power supply device is a terminal L21 in FIG. 2, and when the first signal is transmitted from the power supply device, the predetermined signal is transmitted to the power supply device. The means for doing this is the sub-microcomputer L1 shown in the second figure. <Effects of the Invention> According to the present invention, even if an accessory unit is not installed in the power supply device, or a unit that should not be installed in the power supply device, for example, a malfunctioning accessory unit is installed, the power supply device will not be erroneously installed. Power supplies and accessory units that can prevent excessive current from flowing and enable safe and efficient power supply.
and power supply system.

[Brief explanation of drawings]

Fig. 1 is a conceptual diagram of the present invention, Fig. 2 is an example of the configuration of the power supply device, Fig. 3 is an example of the main part of the main interface circuit, and Fig. 4 is the feeding relationship between the lens unit and the camera body. Figure 5 is a diagram showing details of the circuit shown in Figure 3, Figure 6 is a flowchart showing the operation of the camera body when the lens unit is attached,
Fig. 7 is a flowchart showing the operation of the lens unit when the lens unit is attached to the camera body, and Fig. 8 is a flowchart of the transmission operation from the lens unit in response to the command "TEST ID". DESCRIPTION OF SYMBOLS 1... Power supply device, 2... First device, 3... Power supply, 4... Detection means, 5... Control means, 7... Power supply means.

Claims (1)

[Scope of Claims] 1. A power supply device having a removable accessory unit having a drive system that converts electric power into mechanical energy, and supplying power to the accessory unit, the power supply device having a connection with the accessory unit. A power supply means that becomes capable of supplying power to the unit after the power supply means becomes capable of supplying power to the unit, and after the power supply means becomes capable of supplying power, outputs a first signal to the accessory unit, and outputs a predetermined signal corresponding to the first signal. A power supply device comprising: control means for controlling power supply to the drive system by the power supply means so that the drive system does not operate when a signal is not detected. 2. After the power supply becomes possible, a first signal is output, and when a predetermined signal corresponding to the first signal is not detected, a drive system that converts electric power into mechanical energy is prevented from operating. an accessory unit detachably attached to a power supply device, the accessory unit having a control means for controlling power supply for the drive system by a power supply means, the receiving means receiving power supply from the power supply device; An accessory unit comprising: means for transmitting the predetermined signal to the power supply device when the predetermined signal is transmitted from the receiving means; and the drive system that converts the electric power received by the receiving means into mechanical energy. 3. A power supply means that becomes capable of supplying power to the accessory unit after connection with the accessory unit, and outputs a first signal to the accessory unit after the power supply means becomes capable of supplying power to the accessory unit, and outputs a first signal to the accessory unit; control means for controlling power supply to the drive system by the power supply means so that the drive system for converting electric power in the accessory unit into mechanical energy does not operate when a corresponding predetermined signal is not detected; a power supply device comprising: a receiving means for receiving power supply from the power supply device; a means for transmitting the predetermined signal to the power supply device when the first signal is transmitted from the power supply device; A power supply system comprising the drive system for converting electric power into mechanical energy, and comprising the power supply device and a detachable accessory unit.