Camera attached with auxiliary device

• US 5,557,365 A
• Filed: 03/09/1994
• Issued: 09/17/1996
• Est. Priority Date: 03/10/1993
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Ohsawa, Toshifumi
• Primary Examiner(s): Gray, David M.
• Application Number:
  US08/208,137
• Time in Patent Office: 923 Days
• Field of Search: 354/127.12, 354/173.1, 354/286, 354/418, 354/484
• US Class Current: 396/279
• CPC Class Codes: G03B 17/14 interchangeably
• CPC Class Codes: G03B 7/26 Power supplies; Circuitry or arrangement to switch on the power source; Circuitry to check the power source voltage

Abstract

This invention relates to a battery check circuit of a camera which mounts, e.g., an interchangeable lens. In this invention, the number of motors in the interchangeable lens is informed to the camera via a communication, and a battery check level according to the number of motors is automatically set, thereby performing a high-precision battery check operation.

Claims

1. A camera system which is constituted by a plurality of auxiliary devices comprising different loads driven by a power supply of a camera, and a camera which interchangeably mounts said auxiliary devices, comprising:

(a) detection means for detecting a load state of the auxiliary device mounted on said camera;

(b) setting means for setting a battery check level in accordance with the load state detected by said detection means, said setting means setting a different level in accordance with the load state of the mounted auxiliary device if the load is different; and

(c) a check circuit for performing a battery checking operation of a power supply output on the basis of the battery check level.

2. A system according to claim 1, wherein said detection means detects the number of actuators in the mounted auxiliary device, and said setting means sets the battery check level in accordance with the detected number of actuators.

3. A system according to claim 1, wherein said detection means detects an electrical power consumption level of the load of the mounted auxiliary device, and said setting means sets the battery check level in accordance with the detected electrical power consumption level.

4. A system according to claim 1, wherein said auxiliary device is an interchangeable lens device.

5. A system according to claim 1, wherein said check circuit inhibits an operation of said camera based on the check result when the check result indicates that the power supply output is lower than a check level.

6. A system according to claim 1, wherein said auxiliary device is connected to said camera via a contact, and transmits data indicating the load state to said camera via said contact.

7. A camera system which is constituted by a plurality of auxiliary devices each comprising a plurality of loads driven by a power supply of a camera, and a camera which interchangeably mounts said auxiliary devices, comprising:

(a) a communication circuit for transmitting information corresponding to an output of the power supply of the camera to a mounted auxiliary device; and

(b) a regulation circuit, said circuit being provided to the auxiliary device, for regulating the number of loads which are simultaneously driven, on the basis of the transmitted information.

8. A system according to claim 7, wherein said regulation circuit comprises a set circuit for setting the number of loads, which are simultaneously driven, on the basis of the transmitted information, and a control circuit for, when the loads corresponding to the number of loads set by said set circuit are simultaneously driven, starting a driving operation of another load after waiting for the end of a driving operation of at least one of the driven loads.

10. A system according to claim 7, wherein said mounted auxiliary device is an interchangeable lens device.

9. A camera system which is constituted by a plurality of auxiliary devices each comprising a plurality of motors driven by a power supply of a camera, and a camera which interchangeably mounts said auxiliary devices, comprising:

(a) a switching circuit for switching driving speeds of motors on the basis of an output from the power supply.

11. A system according to claim 9, wherein said mounted auxiliary device is an interchangeable lens device.

12. A camera system which is constituted by a plurality of auxiliary devices comprising different loads driven by a power supply of a camera, and a camera which interchangeably mounts said auxiliary devices, comprising:

(a) detection means for detecting a load state of the auxiliary device mounted on said camera;

(b) vary means for varying a battery check level in accordance with the load state detected by said detection means; and

(c) a check circuit for performing a battery checking operation of a power supply output on the basis of the battery check level.

13. A camera which interchangeably mounts a plurality of auxiliary devices comprising different loads driven by a power supply of a camera, comprising:

(a) detection means for detecting a load state of the auxiliary device mounted on said camera;

(b) vary means for varying a battery check level in accordance with the load state detected by said detection means; and

(c) a check circuit for performing a battery checking operation of a power supply output on the basis of the battery check level.

14. A camera system which is constituted by a plurality of auxiliary devices comprising different loads driven by a power supply of a camera, and a camera which interchangeably mounts said auxiliary devices, comprising:

(a) detection means for detecting the auxiliary device mounted on said camera;

(b) vary means for varying a battery check level in accordance with a detection result by said detection means; and

(c) a check circuit for performing a battery checking operation of a power supply output on the basis of the battery check level.

15. A camera which interchangeably mounts a plurality of auxiliary devices comprising different loads driven by a power supply of a camera, comprising:

(a) detection means for detecting the auxiliary device mounted on said camera;

(b) vary means for varying a battery check level in accordance with a detection result by said detection means; and

(c) a check circuit for performing a battery checking operation of a power supply output on the basis of the battery check level.

16. An auxiliary device having a plurality of motors driven by a power supply of a camera, comprising:

(a) a switching circuit for switching driving speeds of motors on the basis of an output from the power supply.

17. An auxiliary device having a plurality of loads driven by a power supply of a camera, comprising:

(a) a communication circuit for performing a communication with the camera; and

(b) a regulation circuit for regulating the number of loads, which are simultaneously driven, on the basis of information corresponding to an output of the power supply transmitted by said communication circuit.

18. A camera system which is constituted by an accessory device including a plurality of load members and by a camera to which the accessory device is detachably mounted, the camera system comprising:

(a) a detection circuit for detecting a voltage of a power supply of the camera;

(b) a set circuit for setting data corresponding to the detection result by said detection circuit;

(c) a communication circuit for transmitting the data set by said set circuit to a receiving circuit of the accessory device; and

(d) a driving control circuit for setting a number of load members which are simultaneously driven in accordance with the data of the receiving circuit.

19. A camera system according to claim 18, wherein said accessory device comprises at least three load members, and said driving control circuit simultaneously drives two load members when the set number of load members according to the data is two, and said driving control circuit starts to drive other load members when the driving of at least one of the load members is completed.

20. A camera system according to claim 18, wherein the accessory device is an interchangeable lens.

21. A camera system which is constituted by a plurality of accessory devices having a different load circuit from each other and by a camera to which the accessory device is interchangeably mounted, the camera system comprising:

(a) a data circuit of the load circuit provided to the accessory device;

(b) a communication circuit for transmitting data of the data circuit to a receiving circuit of the camera; and

(c) a set circuit for setting a detection level of a voltage detection circuit of the camera in accordance with the data received by the receiving circuit.

22. A camera system according to claim 21, wherein said set circuit has a memory circuit from which information having a different detection level is read as a function of the data.

23. A camera system according to claim 22, wherein the accessory device is an interchangeable lens.

24. A camera system which is constituted by a camera to which an accessory device having a motor is detachably mounted, the camera system comprising:

(a) a detection circuit for detecting a voltage of a power supply of the camera;

(b) a set circuit for setting data corresponding to the detection result by said detection circuit;

(c) a communication circuit for transmitting the data set by said set circuit to a receiving circuit of the accessary device; and

(d) a speed adjustment circuit for setting a driving speed of the motor in accordance with the data of the receiving circuit.

25. A camera system according to claim 24, wherein the accessory device comprises a plurality of motors including at least a first and second motor, and said speed adjustment circuit has a selection circuit which selects one of a different-speed state and another state, wherein, in the different-speed state, the first and the second motors are controlled to operate at different speeds.

26. A camera system according to claim 24, wherein the accessory device is an interchangeable lens.