US 3551906 A
Description (OCR text may contain errors)
1366- 1970 1.. A. COOPER REMOTE CONTROL ALARM SYSTEM 3 Sheets-Sheet 1 Filed April 28, 1967 ATTORNEY 1970 A. COOPER REMOTE CONTROL ALARM SYSTEM Filed April 28, 1967 3 Sheets-Sheet. 2
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Filed April 28, 1967 mow h. oom
21 4 3 EMNNDQ United States Patent 01 ice 3,551,906 REMOTE CONTROL ALARM SYSTEM Leslie A. Cooper, Garden City, N.Y.
(IEO. Box 3392, St. Thomas, Virgin Islands 00801) Filed Apr. 28, 1967, Ser. No. 634,547 Int. Cl. G08b 13/22 US. Cl. 340-224 2 Claims ABSTRACT OF THE DISCLOSURE This invention relates generally to a remote control alarm system for protecting portable or mobile articles and, more particularly, pertains to an alarm system in which the alarm indicating device is carried by the article to be protected and may be selectively actuated from a place remote from the article.
Presently, some alarm systems are available to protect against the theft of portable articles. However, these systems have been found to be both expensive and inefficient. For example, most of these systems utilize a central alarm indicating apparatus which is usually remotely located with respect to the protected article. Accordingly, during the time interval which elapses between the operation of the alarm indicating apparatus and the appearance of a guard, the article easily is removed. Other types of systems utilize an alarm sounding device which is mounted on the article to be protected. However, these systems usually include elaborate sensing devices to protect against the removal of the article and to actuate the alarm sounding device. Hence, the cost of these devices is exceedingly high. Moreover, these latter systems usually require certain conditions to be met prior to setting the alarm; a condition which places an undue burden on the person protecting the article. As an illustrative example, the operator of a car must first close all the windows and the doors of the automobile before setting a so-called car alarm. Thus, if the operator is required to make a number of stops, this procedure becomes extremely bothersome, particularly during periods of warm weather when open car windows are a necessity.
Additionally, messengers carrying valuable items such as stock certificates, jewelry, payrolls, etc. are constantly being :burglarized because it is exceedingly difficult to provide them with devices which are adapted to produce an alarm indication. Moreover, the messengers are deterred from preventing such thefts because of the dire consequences which may result from actions of this type. Accordingly, an object of the present invention is to provide an alarm system for protecting an article which includes an alarm indicating device which is carried by the article to notify people in the vicinity that the article is being removed by unauthorized personnel.
Another object of the present invention is to provide 3,551,906 Patented Dec. 29, 1970 an alarm system which is simple in construction and eflicient in operation.
A further object and feature of the present invention resides in the novel details of construction which provide an alarm system of the type described which includes a portable transmitter for operating a remote alarm indicating device.
Another object of the present invention is the provision of an alarm system wherein an alarm indicating device may be selectively operated by authorized personnel after they have moved out of the range of a thief, thereby to protect themselves from possible harm.
A further object of the present invention is to provide an alarm system which is reliable in operation.
In furtherance of the above objects, one embodiment of an alarm system constructed according to the present invention includes a portable transmitting device and a receiving device which is carried by the article which is to be protected. The receiving device includes an alarm indicating device and means for operating the alarm indicating device in response to the detection of an alarm signal. The transmitting device includes a transmitter which is adapted to generate the alarm signal. An energizing means is included in the transmitting device for energizing the transmitter. A switch is connected between the energizing means and the transmitter for selectively connecting together the energizing means with the transmitter to generate the alarm signal. Accordingly, the transmitting device may be operated from a location remote from the receiver to cause an alarm to be emitted from the protected article to notify people surrounding the article that the article is being taken by unauthorized personnel.
Other objects and features of the present invention will become more apparent from a consideration of the following detailed description, when taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a front elevational view, with parts broken away, of an alarm system constructed according to the present invention in combination with a device for carrying valuables;
FIG. 2 is a perspective view of the device shown in FIG. 1, with the top cover in the open position;
FIG. 3 is a schematic circuit wiring diagram of the transmitting device of the alarm system of the present invention; and
FIG. 4 is a schematic circuit wiring diagram of the receiving device of a modified embodiment of an alarm system adapted to be used in conjunction with a mobile article such as a truck or the like.
The device shown in FIGS. 1 and 2 comprises a carrying case which is designated in general by the numeral 10. Received within the carrying case is the receiving section, designated generally by the reference numeral 12, of an alarm system, a schematic circuit wiring diagram of the transmitting section of which is shown in FIG. 3. The receiving section 12 includes an alarm-indicating device as noted in greater detail hereinbelow, which is adapted to produce an audible alarm when the alarmindicating device is energized to notify people in the vicinity of the carrying case 10 that the carrying case has been removed by unauthorized personnel.
More particularly, the carrying case 10 includes a front wall 14, a rear wall 16, opposed side walls 18 and 20, and a bottom wall 22. A cover 24 is connected to the rear wall 16 by longitudinally spaced hinges 26 so that the interior of the case defined by the walls 14, 16, 18, 20
and 22 may be respectively opened and closed by the cover 24. The upper surfaces of the walls 14, 16, 18 and 20 form a continuous upper edge 28 and the cover 24 is provided with a continuous lower edge 30. The edges 28 and 30 are provided with complementary formed grooves which form a rabbet joint when the cover 24 is in the closed position.
A conventional clasp-type lock 32 is mounted on the front wall of the cover 24 and is adapted to be engaged with a keeper mounted on the front wall 14 of the bottom portion of the carrying case 10 to securely lock the cover 24 in the closed position to prevent access to the interior of the carrying case. Additionally, the top wall of the cover 24 mounts a handle 34 to facilitate carrying of the carrying case 10.
Spaced above and parallel to the bottom wall 22 of the carrying case 10 is a partition 36 which is maintained in spaced relationship to the bottom wall 22 by a plurality of brackets, not shown, which are connected to the respective walls defining the case 10. The partition 36 together with the bottom wall 22, front wall 14, rear wall 16, and side walls 18 and 20 define a compartment 38 which houses the receiving section 12 of the alarm system of the present invention. Moreover, the partition 36 essen tially provides a false bottom for the interior of the case 10.
The receiving section 12 includes a receiver 40 which is adapted to detect an alarm signal, as noted in detail hereinbelow. An antenna 42 is connected to the input circuit of the receiver 40 to receive the alarm signals. In practice, the receiver 40 may comprise a receiver of the type manufactured by the Perma-Power Company of Chicago, Ill., and designated as their R27002 series receiver. However, this illustration is by way of example only and is not to be interpreted as being a limitation on the present invention. The output terminals of the receiver 40 are connected to a transistor latching circuit which is designated generally by the numeral 44. The latching circuit 44 includes an NPN transistor 46, the emitter electrode of which is connected to ground and the collector electrode of which is connected to an input terminal of respective siren amplifiers 48 and 50 through the winding of a relay 52 by a lead 54. The input terminal of the siren amplifiers 48 and 50 are connected to the cathode electrode of diode 56 by a lead 58. The anode electrode of the diode 56 is connected to the collector electrode of the transistor 46. The siren amplifiers 50 and 48 are conventional in construction and are adapted to produce a siren signal when they are energized in the manner indicated below. Also connected to the cathode electrode of the diode 56 is the normally unconnected armature 52a of the relay 52. The armature 52a is adapted to engage a contact 52b, which is connected to ground, when the relay winding 52 is energized. The positive terminal of a source of potential 60 is connected to the lead 54; it is to be understood that the other terminal of the source of potential is connected to ground.
A loudspeaker 62 is connected to the output terminals of the siren amplifier 48 by leads 64. Similarly, the loudspeaker 66 is connected to the output terminals of the siren amplifier 50 by leads 68. The speakers 62 and 66 are mounted on the respective side walls 18 and 20 by conventional mounting means, such as brackets. The walls 18 and 20 are provided with a plurality of apertures 70 to provide for the passage of the sound waves from the respective speakers 62 and 66 through the walls of the carrying case 10.
The receiver 40 is energized by a source of energy 72 which is connected to the receiver 40 through a keyoperated single-pole single-throw switch 74. The switch 74 is accessible through an opening 76 in the partition 36 so that the operator may connect the source of energy 72 with the receiver 40 by inserting the appropriate key into the lock 74 through the opening 76 and operating the switch to the closed position. In practice, the source of energy 72 comprises a rechargeable battery of the nickelcadmium type. Accordingly, the recharging terminals of the battery are connected to a male socket 78 by leads 80. The socket 78 is mounted on the wall 20 by appropriate mounting means (not shown) and the socket is accessible through an opening 82 in the side wall 20 so that a female socket, which may be connected to a recharging source, may be connected to the battery 72 through the leads and the male socket 78 to recharge the same.
The transmitting device of the present invention comprises a compact unit which may easily be held in the hand of the operator. In practice, such a transmitting device is manufactured by the above-identified Perma- Power Company of Chicago, Ill., and designated Portable Transmitter 6-370 series. A transmitting device of this type is illustrated in FIG. 3.
Accordingly, the transmitting device, which is designated generally by the reference numeral 84, includes a first NPN transistor 86 the emitter electrode of which is connected to ground through a parallel circuit 88 comprising a resistor and a capacitor. The collector electrode of the transistor 86 is connected to ground through a tuned circuit comprising an inductor 90 and a capacitor 92 and a capacitor 94 by a lead 96. The base electrode of the transistor 86 is connected to the capacitor 94 through a resistor 98 by a lead 100. Connected between the base electrode of the transistor 86 and ground is a crystal 102 and a resistor 104. The transistor 86 functions as an oscillator stage which oscillates at the frequency determined by the crystal 102. The positive terminal of a source of potential 106, which may comprise a conventional dry cell battery or the like, is connected to the lead 96 between the capacitor 94 and the tuned circuit 90, 92, through a normally open pushbutton switch 108 by a lead 110. The negative terminal of the source of potential 106 is connected to ground. Also connected to the lead 110 is the emitter electrode of a PNP transistor 112. The base electrode of the transistor 112 is connected to a plugin channel selector which is designated generally by the numeral 114, through serially connected resistor 116. The base electrode of the transistor 112 is also connected to ground through a resistor 118. The channel selector 114 is removably connected to the remainder of the circuits comprising the transmitting device 84 so that different channel selector units may be utilized to produce different alarm signals so that a particular receiving device will be sensitive to only the particular transmitting device or transmitting section 84.
The plug-in channel selector 114 includes terminals 120, 122 and 124. The terminal is connected to the lead 110; the terminal 122 is connected to the base electrode of the transistor 112 through the resistor 116; and, the terminal 124 is connected to ground. Within the plugin unit 114, the terminal 122 is connected to the collector electrode of an NPN transistor 12 8 by a lead 130. The emitter electrode of the transistor 128 is connected to the terminal 124 through a parallel circuit comprising the resistor 132 and an electrolytic capacitor 134, the positive terminal of which is connected to the emitter electrode. Connected between the terminal 124 and the base electrode of the transistor 128 is a resistor 136. The base electrode of the transistor 128 is also connected to the collector electrode of the transistor through a series circuit comprising a resistor 138 and a capacitor 140. Connected in parallel with the capacitor 140 is a coil 142 having a center tap which is connected to the terminal 120. The channel selector 114 provides a signal which is applied to the transistor 112. The transistor 112 operates as a modulator stage.
More specifically, the collector electrode of the transistor 112 is connected to the center tap of an antenna 144 by a lead 146. The lead 146 is also connected to ground through a capacitor 148. Connected between one end of the antenna 144 and the lead 146 is a fixed capacitor 150 and a variable capacitor 152 which tunes the antenna 144 to resonance.
Connected to the other end of the antenna 144 is a radio frequency amplifier comprising a transistor 154. The collector electrode of the transistor 154 is connected to the antenna 144 by a lead 156. The emitter electrode of the NPN transistor 154 is inductively coupled to the tuned circuit 90, 92 through a coil 158; one end of which is connected to the emitter electrode of the transistor 154 and the other end of which is connected to ground.
Accordingly, it will be obvious from the above description that when the push-button 108 is depressed the source of potential 106 will be connected to the trans mitting section or device 84 thereby to energize the same. More particularly, the oscillator stage including the transistor 86 will produce a carrier signal which will be amplified by the radio frequency amplifier stage which includes the transistor 154. This signal will be applied to the antenna 144. Similarly, the modulator stage which includes the transistor 112 and the plug-in channel selector 114 will cooperate to produce a modulating signal which will similarly be applied to the antenna 144. Accordingly, the antenna 144 will then transmit an alarm signal which will be detected by the receiver 40 in the receiving section 12 of the present system.
In operation, the cover 24 of the carrying case is pivoted to the open position so that the valuables which are to be received within the interior of the carrying case may be placed therein. Thereafter the cover is moved to the closed position and securely locked in this position by means of the lock 32. However, prior to the introduction of the valuables the key-operated switch 74 is moved to the closed position thereby to connect the source of energy 72 with the receiver 40. The transmitting section or device 84 which, as noted hereinabove, is a compact unit, is easily carried on the body of the messenger. Thus the messenger grasps the carrying case by the handle 34 to transmit the valuables from one location to another.
Assuming that the messenger in charge of the carrying case 10 is accosted by a thief during the interval that he is transmitting the valuables from one location to another, he readily gives the thief the carrying case to prevent harm to himself. Since the cover of the carrying case is securely locked it is doubtful whether a thief will at that time begin to tamper with the lock and try to open the same. It is more probable that the thief will remove both the carrying case 10 and himself from the site of the theft. Thus as the thief moves away from the messenger, the messenger depresses the push-button 108 thereby to connect the source of potential 106 with the transmitting section 84 to cause'the transmission of an alarm signal. The receiver 40 will detect the alarm signal thereby to cause the transistor 46 and the transistor latching circuit 44 to conduct. When the transistor 46, which is normally shut off, begins to conduct, the relay winding 52 will be energized thereby to cause the armature 52a to be connected to the contact 52b. This action causes a lead 58 to be connected to ground. Thus, the siren amplifiers 48 and 50 will be energized through the circuit comprising the source 50, the leads 54 and 58, armature 52a, the contact 5222, and the ground. Accordingly, the loudspeakers 62 and 66 will emit a loud siren-type noise thereby to notify people in the vicinity that the carrying case 10 is in the possession of unauthorized personnel. At this point, it is more than likely that the thief will drop the carrying case rather than to attempt to get away from the scene with the carrying case emitting this loud noise.
It is to be noted that the interval during which the alarm signal is transmitted may be only momentary since the operation of the relay 52 will cause a holding circuit to be established around the relay winding. To be more specific, when the lead 58 is connected to ground through the relay armature 52a and the contact 52b, the diode 56 will begin to conduct through the circuit comprising the source 60 the relay winding 52, the diode 56, and the relay armature and contact 52a and 52b; respectively. Thus, even through the transistor 46 may again be cut off, as when the alarm signals emitted by the transmitting section 84 are terminated, the siren amplifiers 48 and 50 will remain energized. 'Hence, it will be noted that the amplifiers 48 and 50 and their respective loudspeakers 62 and 66 provide an alarm-indicating device which will deter the unauthorized removal of the carrying case 10.
Accordingly, a remote control alarm system including a portable transmitting device has been provided in which the alarm-indicating device may be carried by the object to be protected to notify people in the vicinity that the object is in the possession of unauthorized personnel.
FIG. 4 illustrates a schematic circuit wiring diagram of a modified embodiment of the receiving section of the transmitting system of the present invention. The embodiment shown in FIG. 4 is particularly adapted to be used in a mobile article such as a truck or the like.
The receiving section of the embodiment of FIG. 4, which is designated generally by the reference numeral 160, similarly includes a receiver 40 and an antenna 42 which is connected thereto. The antenna 42 is insulated from the automobile body by means of a feed-through capacitor 162 which is connected to ground through a lead 164. The receiver 40 is adapted to be energized by means of a source of potential 166 which may comprise the storage battery of the automobile. Thus, the negative terminal to battery 166 is connected to ground. The positive terminal of the battery 166 is connected to the input terminal of a normally open single-pole single-throw switch 168 by a lead 170. The output terminal of the switch 168 is connected to an input terminal of the receiver 40 by a lead 172. The other input terminal of the receiver 40 is connected to ground by a lead 174. The output terminal of the receiver 40 is connected to ground through the winding of a relay 176. The relay 176 includes armatures 176a and 1761; which are adapted to be connected to terminals 1760 and 176d, respectively, when the relay winding 176 is energized. The armature 176a is connected to ground by a lead 178. The armature 176b is conected to the lead 172 through a resistor 180 by a lead 182. The terminal 176 is connected to ground through the winding of a relay 184. The terminal 1760 is connected to one contact associated with an armature 188a of a double-pole single-throw switch 188, by a lead 186. Connected to the armature 188a is the input terminal of a tape playback device 190. The other input terminal of the device 190 is connected to the lead 172 by a lead 192. The device 190 is adapted to broadcast a prerecorded message via an associated loudspeaker (not shown) when the device is energized in the manner indicated hereinbelow. The switch 188 further includes an armature 18% which is connected to the lead 172 through a lamp 194. The armature 18817 is adapted to engage an associated contact which is connected to ground thereby to provide a complete circuit from the lead 172 through the lamp 194 to ground.
Connected between the armature 184a and the relay 184 and an armature 196a of a double-pole single-throw switch 196 is a lead 198. Resistor 200 is serially connected between the armatures 196a and 184a. The armature 196a is adapted to engage in associated contact which is connected to an input terminal of a buzzer alarm 202 when the switch 196 is closed. The other input terminal of the buzzer 202 is connected to ground by a lead 204.
The switch 196 also includes an armature 1961) which is connected to the lead 172 through a lamp 206. The armature 19611 is adapted to engage an associated contact in which is connected to ground by a lead 208.
Also connected to the lead 198 through a resistor 210 is the armature 212a of a double-pole single-throw switch 212. The armature 212a is adapted to engage in associated contact which is connected to an input terminal of a siren alarm 214 by a lead 216. The other input terminal of the alarm 214 is connected to ground by a lead 218.
Similarly to the switches 188 and 196, the switch 212 includes an armature 21211 which is connected to the lead 172 through a lamp 220. Additionally, the armature 21217 is adapted to engage in associated contact which is connected to ground via a lead 222.
A pilot light or power lamp 224 is connected between the lead 172 and ground. As will be obvious from a consideration of the operation of the receiving section 160, as noted hereinbelow, the lamp 224 will be illuminated when the switch 168 is closed to indicate that power has been applied to the receiving section.
The buzzer alarm 202 is conventional in construction and is adapted to emit a loud buzzing noise when it is energized. Similarly, the siren alarm 214 is adapted to produce a siren-like noise when it is energized. Additionally, the elements enclosed within the left-hand dashedline box of FIG. 4 may conveniently be located either on the dashboard of the vehicle or beneath the dashboard of the vehicle so that they will be easily accessible to the operator of the vehicle.
In operation, when the operator of the vehicle is about to leave the vehicle, he closes the switch 168 thereby to connect the battery 166 with the lead 172. Thus, power will be applied to the receiver 40. Moreover, the lamp 224 will be energized through the circuit comprising the lead 170, switch 168, and lead 172 to indicate that power has been applied to the receiving section 160.
The operator may then selectively close any one or more of the double-pole single-throw switches 188, 196 or 212. In this particular illustration it will be assumed that the operator has closed all three switches 188, 196 and 212. Thus, the lamps 194, 206 and 220 will be energized through the circuit comprising the energized lead 172 and the respective armatures 188b, 19611 and 212b, which will be connected to ground via their associated contacts. The illuminated lamps 194, 206 and 220 indicate that the devices associated with these lamps will be energized when the receiver 40 is actuated in response to an alarm signal. In other words, the illumination of one of the indicating lamps such as lamp 220 indicates that the siren alarm 214 will be energized when the receivcr 4.0 is operated in response to a transmitted alarm signal. It will be obvious that if any of the switches 188, 196 or 212 were left in the open state, the associated lamp would not be illuminated.
As noted hereinabove, the receiver 40 is adapted to energize the relay winding 176 when an alarm signal is emitted from the transmitting section 84 shown in FIG. 3. As further noted hereinabove, the transmitting section or device 84 is adapted to be carried on the person of the operator. Accordingly, when the operator notices unauthorized personnel enter the vehicle containing the receiving section 160 and begin to drive the vehicle away, he simply operates the transmitting section thereby causing the emission of the alarm signal.
When the receiver 40 detects an alarm signal the relay winding 176 will be energized. It is to be understood that a transistor latching circuit similarly to the transistor latching circuit illustrated in FIG. 1 is associated with the relay winding 176 so that the relay winding will remain energized albeit transmission of the alarm signal ceases shortly thereafter and will remain energized until reset by hand.
Accordingly, when the relay winding 176 is energized the armatures 176a and 176b will engage the respective contacts 176C and 176a. Accordingly, the tape playback device 190 will now be energized through the circuit comprising the energized lead 172, the lead 192, the device 190, the switch 188, the lead 186, and through the closed armature 176a and the contact or terminal 1760 and lead 178 to ground. Thus, the playback device 190 will begin to broadcast a prerecorded message that the automobile is being removed by unauthorized personnel.
Additionally, when the armature 176b engages the contact 176d the relay winding 184 will be energized through the circuit comprising the energized lead 172, the lead 182, resistor 180, armature 176b, terminal or contact 176d and the relay winding 184 to ground. Thus, the armature 184a will engage the contact 1841) thereby to apply the source of potential or the battery 166 to the lead 198 through the energized lead 182. Hence, the buzzer alarm 202 will be energized through the circuit comprising the energized lead 198, resistor 200, and armature 196:: of the switch 196 to ground. In a similar manner the siren alarm 214 will be energized through the circuit comprising the energized lead 198, the resistor 210, armature 212a of the switch 212, and leads 216 and 218 to ground. Hence, the buzzer alarm 202 and the siren alarm 214 will simultaneously emit their respective sounds to further notify people in the vicinity of the automobile that the automobile is in the process of being stolen.
It is obvious from a consideration of the above description, that if anyone of the switches 188, 196 or 2 12 is not operated, the alarm-indicating device associated with that particular switch will remain inoperative albeit the relay winding 176 will be operated by the receiver 40. For example, if the switch 196 remains open then the energized lead 198 will not be connected to the buzzer alarm 202. Hence, the operator may selectively determine which one of the alarm-indicating devices 190, 202 or 214 is to be energized in the event that the automobile is stolen simply by selectively operating the desired one or more of the switches 188, 196 or 212.
Accordingly, a receiving section of a modified embodiment of the system of the present invention has been disclosed which is ideally suited for use in a mobile article to protect the same against theft and which is selectively operable to produce one or more types of alarm-indicating signals to notify people in the vicinity that the article is being stolen.
While preferred embodiments of the present invention have been shown and described herein, it will be obvious that numerous omissions, changes and additions may be made in such embodiments without departing from the spirit and scope of the present invention.
What is claimed is:
1. In combination, a portable alarm device and a case to be protected, said alarm device including alarm-indicating means for producing an alarm, energizing means for energizing said alarm indicating means, switch means connected between said alarm-indicating means and said energizing means and being operable between an open and closed state to connect said energizing means with said alarm-indicating means when said switch means is operated to the closed state, and a receiver operable in response to the reception of a broadcast alarm signal for operating said switch means to the closed state to energize said alarm-indicating means whereby an alarm is produced, said case comprising a housing having an open top, a cover connected to said housing for closing the open top of said housing, and a compartment in said housing receiving said alarm device therein, whereby said alarm device may be actuated when said case is taken by unauthorized personnel to indicate that a theft has occurred, and a portable selectively operable alarm transmitter adapted to be carried on the body of a person for broadcasting said alarm signal to said receiver when it is desired to produce said alarm, said housing including a bottom wall, a partition in said housing overlying said bottom wall, said partition and said bottom wall defining said compartment in said housing, whereby said partition provides a false bottom for said case, key-operated switch means connected between said receiver and said energizing means and being operable between a first state to connect said energizing means with said receiver and a second state to disconnect said energizing means for said receiver, means for mounting said key-operated switch means on said partition, whereby said key-operated switch means is accessible only through the open top of said housing, said energizing means comprising a rechargeable battery, removable connecting means for connecting a recharging source with said energizing means, said removable connecting means including a male socket mounted on said housing, and an opening in said housing aligned with said socket to provide a passage for the connection of the female member to said male socket.
2. An alarm system as in claim 1, in which said alarmindicating means includes a tape playback device, and an audio-alarm; a disconnect means for each of said tape playback device and said audio alarm operable between a first state to connect the responsive tape playback device and audio-alarm to said switch means and a second state to disconnect said tape playback device and said audioalarm, respectively, from said switch means and indicating means to indicate that the respective disconnect means are in the first state.
References Cited UNITED STATES PATENTS 2,03 8,625 4/1936 Adler 340280 2,905,762 9/ 1959 Rettie et a1. 340224X 2,927,311 3/ 1960 Donaldson 340-280X 3,056,951 10/ 1962 Tooni 340224 3,157,871 11/ 1964 Umanoif 3402'80 3,247,502 4/ 1966 Eberts 340280 1,993,436 3/1935 Eberhard 340224 3,051,934 8/1962 'Lesher 340-224 ALVIN H. WARING, Primary Examiner P. PALAN, Assistant Examiner US. Cl. XJR. 340-280