US3015272A

US3015272A - Intermittent arming device for a mine

Info

Publication number: US3015272A
Application number: US125362A
Authority: US
Inventors: Howard W Semon
Original assignee: Individual
Current assignee: Individual
Priority date: 1949-11-03
Filing date: 1949-11-03
Publication date: 1962-01-02
Anticipated expiration: 1979-01-02

Description

Jan. 2, 1962 H. w. SEMON 3,015,272

INTERMITTENT ARMING DEVICE FOR A MINE Filed Nov. 3, 1949 FIG. 1.

H.W. SEMON United States Patent 3,015,272 INTERMITTENT ARMING DEVICE FOR A MINE Howard W. Semon, Philadelphia, Pa. (1130 Maryland Ave. NE., Washington 2, D.C.) Filed Nov. 3, 1949, Ser. No. 125,362 6 Claims. (Cl. 10216) (Granted under Title 35, US. Code (1952) see. 266) This invention relates to an intermittent arming device for a mine which controls the period of time during which the mine is armed and disarmed respectively, thereby to provide intermittent arming of the mine. Such a device is advantageous in that it increases the labor and difiiculties encountered by the enemy in sweeping a mine infested area since only a fractional number of the mines would be actuated or swept by a single sweeping operation.

The military value of mine warfare, as is well known, is increased by lengthening the useful life of a mine and by decreasing the susceptibility of a mine to sweeping. In prior devices employing intermittent arming of a mine it has been the general practice to control the armed and unarmed periods of the mine from a short station. Such devices have not been altogether satisfactory under all conditions of warfare for the reason that a control connection must be established between the mine and the control apparatus on the shore.

The present invention accomplishes both of the foregoing desirable features by means of time measuring devices which require no outside control or regulation after the initial setting and possesses none of the foregoing disadvantages of the prior devices.

One of the objects of this invention is to provide a system which inherently arms and disarms a mine repeatedly in accordance with predetermined time limits.

Another object of this invention is the provision of separate means for governing the length of the armed period and the length of the disarmed period respectively of a mine.

Another object of this invention is the provision of a device which increases the difficulties of making a complete sweep of a mined area.

Another object of this invention is the provision of a device which lengthens the useful armed life of a mine by making interrupted power demands on the mine battery thereby allowing regeneration of the battery.

Still other objects and advantages of the invention not specifically set forth hereinabove are those implied or inherent in the construction, combination and arrangement of parts, as will become more clearly apparent from the following description, reference being had to the accompanying drawings in which:

'FIG. 1 is a diagrammatic view of the circuit and mechanism of the present invention according to a preferred embodiment thereof; and

FIG. 2 is a sectional view of a specific one'of the timing devices suitable for use with the present invention, the other timing device being identical therewith.

Referring now to the drawings for a more complete understanding of the invention, FIG. 1 thereof discloses a preferred embodiment and comprises four units: (1) the battery power source 3, (2) the firing mechanism 4, (3) the arming clock 5, and (4) the arming and disarming control devices 8 and 9.

. The arming and disarming control devices 8 and 9 are caused to operate upon the closing of contact A of the hydrostatically controlled arming clock 5 which may be of any type suitable for the purpose such, for example, as the arming clock disclosed in the patent to Van Atta et al., for Control System and Device Therefor for Submarine Mines, No. 2,399,523, issued on April 30, 1946.

The arming clock 5 has a pair of cam controlled contacts A and E adapted to be closed in the order named in predetermined time delayed relation in response to the operation of the hydrostat 6 after the mine is planted.

The mine is placed in target-responsive or tar-get nonresponsive condition by the operation of switch B of the armed interval control device 8. As shown in FIG. 1 switch B is included in the circuit of the firing mechanism 4, said firing mechanism being of any type suitable for the purpose such, for example, as the firing mechanism disclosed in the patent to Van Atta et a1. referred to hereinbefore.

The first timing device 8 comprises a shaft 10 on which is mounted a clock type power spring 11 shown in FIG. 2, which has its inner end attached to the shaft 10 and its outer end attached to the frame 26 of the armed condition establishing device 8. A large gear 12 is connected to the lower end of the shaft 10 and is intermittently driven clockwise by a pinion 14 which is powered by an electric motor 15. A mechanical self-starting escapement 16 of any type suitable for the purpose such, for example, as the escapement disclosed in the patent to Van Atta et a1. referred to hereinbefore, is connected to the large gear 12 through a ratchet-type clutch 17 so arranged that the escapement 16 is driven only when the shaft 10 is rotated counter-clockwise by the power spring 11. The escapement 16 controls the rate of rundown of the armed interval control device 8. At the top of shaft 10 is mounted a switch disk 13 which is held secured thereon in any suitable manner as by nut 23-. Integral with the switch disk 13 is a protuberance 18, FIG. 1, arranged to operate switches B and C as the disk rotates. One blade of switch C has a rider 24 attached thereto which is inherently spring-biased toward and slideably contacts the side periphery of the switch disk 13 and the protuberance 18 thereof. The outer blade of switch B is rigidly attached to the switch disk riding blade of switch C by means of insulated rod 25. This arrangement causes switch C to be closed and switch B to be sprung open by rod 25 when the protuberance 18 forces rider 24 outwardly against its inherent inward spring pressure and the inherent inward spring pressure of the B spring blade to which rod 25 is attached.

Immediately below the switch disk 13 is a switch arm 19, as viewed on FIG. 2, pivotally mounted on hearing 33 which is fixedly attached to the upper plate 27 of the clock frame 28. A pin 20 is provided at one end of switch arm 19 which projects into the timing slot 21 of switch disk 13. At the other end of switch arm 19 are provided two switch

blade engaging surfaces

30 and 31 which contact and actuate the inner inwardly springbiased electrical contact blade of switch D which is included in the armed device winding motor circuit. The contact arm 19 is arranged to provide a toggle action so that either switch closing surface 30 or switch opening surface 31 is in contact continuously with the aforementioned inner blade of switch D.

The switch disk timing slot 21 is provided with an adjustable timing slot stop 22 which may be used, in the case of device 8, to set the desired period for which a mine is to be armed. As seen in the drawing in FIG. 1 the switch disk 13 is provided with a plurality of time indicia which are arranged along the timing slot 21. By adjustment of the stop 22 the clockwise windup by motor 15 is regulated since the stop 22 will snap the toggle action contact arm 19 clockwise, as viewed in the drawing, when the switch disk 13 has rotated sufficiently, thereby allowing the inner blade of switch D to spring inwardly into contact with surface 31 thereby to cut off the power at switch D to motor 15.

The unarmed interval control device 9 comprises mechanism similar to the armed interval control device 8 with the exception that switches B and C are replaced by switch F operated by protuberance 18'. The component parts of the unarmed interval control device 9 have the same numerals as similar parts of the armed interval control device 8 and operate in a similar manner but are primed for the purpose of description.

The battery power source 3 is provided to supply the two electric winding motors 15 and 15' with the electrical power needed for each motor to wind the power spring 11 and 11 individual thereto.

The operation of the intermittent arming device for a mine will now be described in detail for a more complete understanding of the invention. Essentially the arming and disarming process involves alternately measuring armed and unarmed time intervals; the measurement of each of the intervals being initiated at the termination of the other interval. The armed time interval device 8 is used to maintain the armed condition of the mine and the unarmed time interval device 9 is used to maintain the unarmed condition of the mine.

With the armed interval control device 8 in fully run down condition, as shown in FIG. 1, the switch disk 13 is in the position shown with the zero time end of slot 21 in engagement with pin 20 thereby holding switch arm 19 counter-clockwise so that switch blade engaging surface 30 springs switch D to closed position. The protuberance 18 is engaging rider 24 thereby causing switch C to be closed and switch B to be opened.

When the mine is laid, arming clock is started and after a predetermined safety period the arming clock 5 causes switch A to be closed which completes the armed interval control device motor circuit and allows current to flow from battery 3, through the closed switch F, through switch D to the electric motor 15, and thence through switch A back to the battery. The pinion 14 and large gear 12 cause the shaft to rotate clockwise, thereby winding the power spring 11. The escapement 16, it will be recalled, is unaffected by clockwise rotation of shaft 10 since the natchet clutch 17 is so arranged that only counter-clockwise rotation of shaft 10, as powered by the power spring 11, aotuates the escapement.

As the switch disk 13 rotates clockwise, switch C is caused to open and switch B is caused to close, thereby placing the firing mechanism 4 in armed condition so that the mine is in readiness to explode upon activation by an enemy vessel. The actual time between the closing of switch A and the opening of switch C may, for example, be about 30 seconds.

Since the interval between the closing of switch A and the closing of switch E of the arming clock 5 need only be long enough to allow the armed switch disk 13 to rotate sufiiciently to open switch C, the arming clock may be set to close switch E at a predetermined time period after switch A is closed, for example 60 seconds. Switch E when closed places the unarmed interval control device motor circuit in readiness to receive current when the armed interval control device 8 runs down and closes switch C.

When the adjustable time slot stop 22, which has been set to the desired armed interval, contacts and pivots the switch arm 19 clockwise, the switch blade engaging surface 31 causes the switch D to open by its inherent spring tension, thereby opening the associated motor circuit and allowing the power spring 11 to rotate the shaft 10 of the armed interval control device 8 counter-clockwise. The counter-clockwise rotation rate of shaft 10 is controlled by the escapement 16 to about 45 degrees of rotation per hour. As stated hereinbefore the ratchet clutch 17 allows actuation of the escapement only when the shaft 10 is rotated counter-clockwise.

The mine, therefore, becomes armed when switch B is closed and becomes disarmed when the switch disk 13 has rotated counter-clockwise sufficiently to close switch C and open switch B.

When switch C is closed current passes from the battery 3 to the unarmed interval control device motor 15', through the closed switch D of the control device 9, through switch C, through switch E and back to the battery 3. The unarmed device motor 15 causes clockwise rotation of the switch disk 13' in the unarmed device 9, which switch disk opens switch F.

After switch F is opened, the zero end of the slot 21 in the armed device switch disk 13 is rotated into engagement with the pin 20 of switch arm 19 and snaps the switch arm 19 counter-clockwise thereby closing switch D of the device 8. The armed device motor circuit is thereby placed in readiness to receive current when the switch F is closed by the unarmed device switch disk 18'. The remainder of the operation of the unarmed device 9, it will be understood, is similar to the armed device 8 operation as described above.

When the unarmed device 9 approaches a rundown condition the protuberance 18' closes switch F which causes the armed device motor 15 to rotate its switch disk 13 clockwise which opens switch C, and closes the mine arming circuit switch B. After switch C is opened the zero end of the slot 21 in the unarmed device switch disk 13' is rotated into engagement with the pin 20 of switch arm 19 and snaps the switch arm 19 counter-clockwise thereby closing switch D' of the device 9. The unarmed device motor circuit is thereby placed in readiness to receive current when the switch C is closed again.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

The terms and expressions used in this specification in reference to my invention are employed as terms of description and not of limitation.

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

What is claimed as new and desired to be secured by Letters Patent of the United States is:

1. A part-time mine arming circuit for a mine comprising, in combination, means for placing the firing mechanism in target responsive condition for a first predetermined period of time, and interrupting means operatively connected to said first-named means for cyclically placing the firing mechanism in a target non-responsive condition for a second predetermined period of time, said means for placing the firing mechanism in a target responsive condition including an armed interval control device having an electric motor, a shaft geared to said motor, a power spring which is wound up by said shaft, a switch disk having a slot therein mounted on said shaft, a protuberance integral with said switch disk, electrical switch means operated by said protuberance for arming circuit energization, a fixed bearing around said shaft, a toggle arm pivotally mounted on said bearing having a pin at one end disposed within the slot in the switch disk and having opening and closing switch engaging surfaces at the other end, switch means for the electric motor located at said other end for operation by said engaging surfaces, a self-starting escapement, and ratchet clutch power transmission means for connecting said escapement to said shaft to allow activation of the escapement only when the shaft is rotated by the power spring.

2. In a part-time arming device for a mine firing mechanism, an armed interval control device which causes the mine to be target responsive for a predetermined period, and an unarmed interval control device which causes the mine to be target non-responsive for a predetermined period, each of said control devices comprising similar timing means adapted to cyclically cause the target responsive and target non-responsive conditions of the mine to be repetitive, wherein one of said similar timing means comprises: means for rapidly supplying power, power receiving and storing means, adjustable means for regulating the amount of power supplied to the receiving and storing means, retarding means for governing the rate of dissipation of the power from the power receiving and storing means, and electrical switch and circuit means for placing the other timing means in readiness for operation.

3. In a part-time arming device for a mine firing mechanism, a power source, a firing mechanism, unarmed interval control means connected to the power source and adapted to maintain the firing mechanism in target nonresponsive condition for a predetermined period; armed interval control means comprising: first power storing means, first means for transferring power from the power source to the first power storing means, first retarding means for dissipating the power in the first storing means at a controlled rate, and first means actuated by the first power transfer means just after the start of operation of the first power storing means for placing the firing mechanism in target responsive condition and for preventing the supply of power to the unarmed interval control means and also just before complete power dissipation for placing the firing mechanism in target non-responsive condition and for allowing the supply of power from the power source to the unarmed interval control means; said unarmed interval control means comprising: second power storing means, second means for transferring power from the power source to the second power storing means, second retarding means for dissipating the power in the second storing means at a controlled rate, and second means actuated by the second power transfer means just after the start of operation of the second power storing means for preventing the supply of power to said armed interval control means and also just before complete power dissipation for allowing the supply of power from the .power source to the armed interval control means; primary control means for stopping the supply of power to the first power storing means after a predetermined amount of power has been supplied and upon complete power dissipation by the first retarding means preparing the armed interval control means for receipt of further power through the unarmed interval control means; and secondary control means for stopping the supply of power to the second power storing means after a predetermined amount of power has been supplied and upon complete power dissipation by the second retarding means preparing the unarmed interval control means for receipt of further power through the armed interval control means.

4. An intermittent arming device for a mine firing mechanism comprising, in combination, a source of power, first and second means for individually storing and releasing predetermined amounts of energy, means individual to said energy storing and releasing means for releasing said energy therefrom in predetermined periods of time, first and second electroresponsive means individual to said energy storage means for transferring said energy thereto from said source of power when the electroresponsive means are selectively connected thereto, means operated by said first energy storing and releasing means for respectively disconnecting and connecting said second electroresponsive means from and to the source of power as storing of energy in said first energy storing and releasing means is initiated and as release of energy therefrom is terminated respectively, means operated by said second energy storing and releasing means for respectively disconnecting and connecting said first electroresponsive means from and to said source of energy as storing of energy in said second energy storing and releasing means is initiated and as release of energy therefrom is terminated respectively, and means operated by said first energy storing and releasing means during said storing and release of the energy thereof for arming the mine firing mechanism.

5. An intermittent arming device for a mine comprising, in combination, a pair of means for successively storing and releasing energy, means individual to said pair of means and controlled by each other for causing energy to be stored in each when release of energy from the other is terminated, means individual to said pair of means for causing release of said energy therefrom at predetermined rates, and means controlled by one of said pair of means for arming the mine during the storing and release of the energy thereof whereby the mine is armed and unarmed alternately for predetermined intervals of time.

6. An intermittent arming device for a mine firing mechanism comprising, in combination, a pair of means for successively storing and releasing energy, means controlled by one of said energy storing and releasing means for initiating storing of energy in the other as release of energy from the one is terminated, means controlled by said other of the energy storing and releasing means for initiating storing of energy in said one of the energy storing and releasing means as release of energy from the other is terminated, means controlled by said one of the energy storing and releasing means for arming said firing mechanism during the energy storing and releasing interval thereof, and means individual to said pair of energy storing and releasing means for causing the energy to be released therefrom at predetermined rates whereby the mechanism is armed and disarmed alternatively for predetermined intervals of time.

References Cited in the file of this patent UNITED STATES PATENTS 2,060,198 Hammond Nov. 10, 1936