Background of the Invention
The present invention relates to a type of automatic gas spray device, particularly to one that automatically spray irritative gas in case of an attack, to hinder criminals.
U.S. Pat. No. 5,034,730, issued to the present inventor, discloses an automatic gas spray device for protection against criminals which can be installed at various locations to automatically spray irritative gas activated by an electronic control main unit and a solenoid sensor for hindering criminals in case of an attack. This automatic gas spray device is effective in use, however, it still has some drawbacks. One drawback of this device is that the electronic control main unit and the solenoid sensor are difficult to install. Another drawback is that the housing must be dismantled when replacement of the gas tank is needed. Further, this structure of automatic gas spray device has no indicator means to indicate the current electric quantity of the battery power supply and the current amount of gas in the gas tank.
Summary of the Invention
The present invention eliminates the aforesaid drawbacks. According to one aspect of the present invention, the casing of the automatic gas spray device has a longitudinally grooved seat at the bottom, a spring at the back, and a male connector connected to a nozzle through a solenoid switch at the front, so that the Gas tank can be quickly installed in position with the female connector on its gas outlet connected to the male connector. According to another aspect of the present invention, a gas volume monitor and a battery power indicator are mounted on the casing to indicate the current volume of gas in the gas tank and the current electric quantity of the battery power supply.
Brief Description of the Drawings
FIG. 1 is a perspective exploded view of an automatic gas spray device of the present invention;
FIG. 2 is a partial sectional view of the gas tank back support of the automatic gas spray device shown in FIG. 1;
FIG. 3 illustrates the relative positions of the gas tank back support and the battery lid on the casing; and
FIG. 4 illustrates the gas tank detached from the solenoid switch.
Detailed Description of the Preferred Embodiment
Referring to FIGS. 1, 2 and 3, a gas tank seat 21 having a longitudinally V-shaped groove is fastened inside a casing 1 to hold a gas tank 2. A spring 42 is fastened to a back cover 4 hinged to the casing 1 at the back. A solenoid valve 3 is fastened to the casing 1 at the front. A nozzle 31 is connected to the solenoid valve 3 at the front outside the casing 1. A male connector 22 is connected to the solenoid valve 3 at the back inside the casing 1. The gas tank 2 has its outlet coupled with a female connector 23. After the gas tank 2 has been positioned in the gas tank seat 21, the female connector 23 is connected to the male connector 22, with the closed end of the tank 2 stopped against the spring 42 to maintain a bias force on the connection of connectors 22 and 23. A gas monitor, such as a pressure gauge 32 is connected to the connection between the solenoid valve 3 and the male connector 22 by a guide tube 321 for monitoring the amount of gas in the gas tank 2. A battery case 52 with positive and negative contacts 511 is fastened inside the casing 1 behind an access hole (not shown) formed therethrough and covered with a battery lid 41 to hold a rechargeable battery 51. By opening the battery lid 41, the rechargeable battery 51 can be slid in and out of the battery case 52. An electronic control main unit 5 is fastened to the battery case 52 inside the casing 1, and controls the production of sound through a speaker 34 for a predetermined time duration and then switches on the solenoid valve 3 to release a flow of irritative gas from the nozzle 31, followed by switching off the solenoid switch to stop the passage of gas to the nozzle 31 after a predetermined time duration. A low voltage indicating lamp 33 is mounted on the outside of casing 1 and is connected to the electronic control main unit 5 to illuminate the lamp when the voltage of the rechargeable battery 51 drops below a predetermined range. When assembled, the casing 1 is covered by a top cover 6 and installed to a wall by a mount 61.