Fail safe interlock method and apparatus

Description

This Application claims benefit of U.S. Provisional Application Number 60/______ filed Mar. 10, 2006.

FIELD OF INVENTION

At the present time hospitals display an illuminated sign or other warning indicator during the radiation procedure to alert personnel of the procedure in progress and not to enter the room. As an added precaution, the doors to the room are sometimes manually locked at this time. However, there are times when the doors are not locked and are accidentally opened during the procedure. When this occurs, there is interruption of the radiation procedure and loss of time and money. The procedure must be restarted and the radiation images are sometimes lost, adding lost time and additional expense for hospitals, their personnel and patients. Also there is the further problem of accidental radiation contamination to personnel and property when the doors are mistakenly opened.

The present invention relates to a method and apparatus for automatically securing and locking all entry and exit passages to and from a radiation room during a medical radiation procedure. The present interlock system is useful for securing an area when any medical radiation procedure is in progress. These procedures include performing x-ray radiations, CAT scans and in nuclear medicine.

SUMMARY OF THE INVENTION

The present invention relates to a fail safe method and apparatus for automatically securing an area during a medical radiation procedure. Upon initiation of the procedure, an electrical signal is sent from the medical device to the locking device, which automatically secures all passages to and from the radiation room. Upon completion of the procedure, a second signal automatically is sent from the medical device thereby opening the locking device and allowing free passage to and from the room.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing a typical electrical interlock system according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

With reference to the drawing, the block diagram of FIG. 1 illustrates one form of an electrical wiring scheme of the present invention.

Upon initiation of the medical radiation procedure, a 24 volt alternating current electrical signal from the medical radiation device (1) is provided to an electrical signal contact (2). Transmission line (3) conducts this signal to a locking device (4), which activates door magnets (5) for securing passageways (6). The door magnets in current use are electromagnetic locks purchased from the Grainger catalogue at www.grainger.com, Item # 4GD82. The transmission line typically comprises 12 gauge copper wire. Included in the transmission line is a relay device (7) containing a 24 volt transformer, which converts the signal from alternating to direct current. The transformer manufacturer is Dormeyer purchased from Grainger catalogue Item # 4×746. The relay in use was also purchased from Grainer Item # 2DT97. There is also included in the transmission line a control device (9) and contacts for inputting a 120 voltage alternating current (10). The control device which is currently installed by the inventor in hospitals is the Securitron Power Supply model BPS-24-2 purchased from Securitron Magnalock Corporation. Website: www.securitron.com.

The present invention also provides for an emergency “on/off” switch (11) (Telemecaniqe manufacturer from Grainger Item # 6HK78). This switch, located in the transmission line (3), is normally in the closed or “on” position and allowing the signal to pass through the circuit. When the switch is turned to the “off” or open position, the signal from the medical device is interrupted. This loss of power shuts down the medical device, deactivates the door magnets and opens the locking device.

When the radiation procedure is completed, a second signal is generated from the radiation device which shuts down the medical device and opens the locking device. The second signal is sent via transmission line (3) to the door magnets (5). In addition if there is a general lose of power to medical device, the door magnets are automatically deactivated and the locking device is opened.