DE69108261T2 - REMOTE CONTROL SYSTEM WITH A KEY-CONTROLLED TRANSMITTER AND A FIXED CODE TRANSMITTER. - Google Patents

Description

BACKGROUND OF THE INVENTION

The present invention relates to a remote control device capable of responding to a plurality of types of security codes, including security codes generated from a memory in a transmitter and security codes generated from a touch pad on a transmitter.

Remote control devices such as automatic garage door openers include remote transmitters and a receiver which responds to signals from the transmitters to generate actuation signals to thereby open a door. The receivers of such devices provide security in their operation by activating only when a suitably transmitted request is received which matches one of a small number of permissible security codes. The security codes are used to deny access to unauthorized persons and to limit the likelihood of someone with a similar transmitter mistakenly opening a garage door other than his or her own.

Two basic types of security code transmitters are known in the art. One type, disclosed in U.S. Patent No. 4,750,118 to C. Heitschel et al., comprises an arrangement which stores a security code for a long time or permanently and which transmits the stored security code in response to depression of a transmit push button switch. Long-term storage of the security code may be provided by a computer-type memory in the transmitter or by a set of switches within the transmitter which are rarely changed. The stored code type of transmitter is extremely simple to use as it requires only the pressing of a transmit button. The security of such an arrangement is equally good due to the large number of possible security codes provided in today's remote control equipment. However, the code of the stored code type transmitter remains in the transmitter and should the transmitter be lost or stolen, others can operate the receiver associated with it simply by pressing a transmit button.

The second basic type of code transmitter does not include long-term security code storage, but instead includes a keypad which the user manipulates to set a special security code which the user has memorized. In effect, the transmitter's long-term storage is replaced by human memory. Thus, the keypad type transmitter can only be used by persons who know the appropriate access code. Should a keypad type transmitter be lost or stolen, it does not include the stored security code to use and thus a person who comes into possession of the transmitter without the owner's permission cannot automatically control a receiver. However, keypad transmitters are less convenient to use than stored code transmitters because the code must be remembered and re-entered each time the keypad transmitter is used. Furthermore, the touchpad code entry may be physically difficult if the user has arms full of packages or if the user is driving a car.

Reference should also be made to EP-A-0 099 762, which describes a remote control for e.g. a garage door using coded signals.

There is a need for a gate operating arrangement which provides security against the loss or theft of a touch panel transmitter while maintaining the simplicity of using a transmitter with a stored code.

SUMMARY OF THE INVENTION

A garage door opening system according to the present invention includes a door operator which responds to door opening request signals from remote transmitters of a touch pad type and from remote transmitters of the long-term storage type by selectively opening a garage door. Advantageously, an operator-controlled safety switch is provided on the door operator which enables the operator to exclude door opening requests of the stored code type while allowing door opening requests of the touch pad type for selectively opening the door.

For normal operation, the operator will open the door and respond to both types of door opening requests. However, if greater security is desired, e.g. if a stored code type transmitter has been lost or stolen, the position of the security switch can be changed to exclude the stored code type transmitter. During the time the stored code type transmitter is excluded, operation by the touch pad type transmitter is still permitted. When greater security is no longer required, e.g. if a lost transmitter has been found, controlling the security switch will again allow door operation by both types of remote transmitters. In one embodiment of the Invention, the gate operating device can further be controlled such that any gate operation is prevented, regardless of the type of gate opening request signals received.

Each type of gate opening request includes a security code sequence that is distinguishable from the security code sequence of other types of gate opening requests. The operator includes a memory for storing approved security code sequences of both the touch pad type and the stored code type. The approved code sequences are those that are allowed to open the gate. In response to a received gate opening request, the gate operator determines the type of request received and compares the security code of the received request with the same type of stored approved code sequence. If the compared code sequences are the same, a gate operating signal is generated. The gate operating signal generated in response to a received gate opening request of the stored code type can be suppressed by setting the security switch.

For even wider applicability, a gate opening device according to the present invention can respond to two formats of stored code type security signals and to the touch pad type security signals. The actuating device comprises a memory for storing at least one authorized stored code of all three possible types of received gate opening requests. When a gate opening request is received, its type and format are determined and it is compared with the same type of stored authorized code sequence. If the compared code sequences are the same, gate actuation signals are generated. When the safety switch is set to be in the enhanced security mode, gate actuation signals are generated in response to both types of stored code transmitters. Security code is suppressed, while those of a touch panel transmitter are not suppressed.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a perspective view showing a garage door operator embodying various features of the present invention.

Figure 2 illustrates a ten-code word security format used in the garage door opening device of Figure 1;

Figure 3 illustrates a twenty-code word security format used in the garage door operator of Figure 1;

Figure 4 is a block diagram of a ten code word transmitter of the stored code type for use with the actuator of Figure 1;

Figure 5 is a block diagram of a twenty code word stored code type transmitter;

Figure 6 is a flow chart of the operation of the transmitter of Figure 5;

Figure 7 is a block diagram of a touch pad type transmitter used in the actuator of Figure 1;

Figure 8 is a flow chart of the operation of the transmitter of Figure 7;

Figure 9 is a block diagram of a control unit of the Actuating device of Figure 1;

Figure 10 is a flow chart showing a programming mode of operation for the transmitter of Figure 9; and

Figure 11 is a flow chart showing the response of the control unit to received security codes.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Figure 1 illustrates a garage door operator 10 mounted on the ceiling of a garage and connected to operate a door 17. The garage door operator 10 includes a head unit 11 supported from the ceiling and including a motor (not shown) which drives a suitable chain 15 to which a trolley 13 is attached for movement along a rail 12. The trolley 13 includes a release cable 20 and pivotally supports a lever arm 14 which is attached to a bracket 16 attached to the door for raising and opening the door by pulling it along conventional rails 19. Similarly, the head unit 11 lowers the door by moving the trolley 13 away from the head unit 11 until the door has reached the closed position.

The head unit 11 includes an actuating mechanism which energizes the motor to open and close the door. The actuating mechanism is actuated in response to an actuating signal transmitted over a conductor 18 from a control unit 38. The control unit 38 generates the actuating signal in the conductor 18 in response to an actuating switch 39 on the control unit 38 and in response to door actuation request signals from remote transmitters 24 to 26. The door actuation request signals from the remote transmitters 24 to 26 each comprise a sequence of code words which must match a sequence of permissible code words stored in the control unit 38 before actuation signals are generated on conductor 18. In the present embodiment, the remote transmitters 24 and 25 transmit in a 10 code word format in which each gate actuation request signal comprises 10 code words, and the remote transmitter 26 transmits in a 20 code word format in which each gate actuation request signal comprises 20 code words.

Figure 2 shows a gate operation request signal of the 10 codeword format in which ten codewords 41 suitably form the security code. Each of the ten codewords 41 comprises 4 bits which are used to carry one of three code designations. The encoding of these three designations, called A, B and C, is shown in Table 1. Since each of the codewords 41 designates one of three states and there are ten such words in a code sequence, approximately 59,000 individual codeword sequences can be generated with the 10 codeword encoding format. CODER WORD REPRESENTATIONS TABLE 1 Transmitted Code Code Character Bit-1

The code words are transmitted from a transmitter to a control unit 38 using RF signals and each sequence of code words begins with a single logical 1 synchronization pulse 42 (Figure 2). After transmission of a complete ten-word code sequence, a blank interval of approximately 39 bit intervals is generated by the transmitter, then the entire code sequence is repeated beginning with the Logic-1 synchronization pulse 42. Transmission in this manner results in a continuous sequence of transmitted 10-word code sequences, separated by the times of 39 blank bits and each beginning with a Logic-1 synchronization pulse 42. The control unit 38 recognizes the 10 code word format, recognizes the format by the presence of the 1-bit time synchronization pulse 42 following a blank interval, and accepts each subsequent sequence of ten code words. As is known in the art, several repetitions of the same code word sequence are received before it is determined that the code word sequence has been received correctly.

Figure 3 shows a 20 codeword sequence of the present embodiment. The 20 codeword sequence of Figure 3 comprises two frames of codewords, wherein frame 1 consists of codewords 1 through 10 and frame 2 consists of codewords 11 through 20. The codewords of frame 1 are designated 44 and those of frame 2 are designated 49. A code sequence of 20 three-state codewords as shown in Figure 3 allows for more than 3 billion individual code combinations.

20-codeword sequences are transmitted in a manner different from the 10-codeword sequences. Each frame 1 is transmitted using substantially the same format as each frame of the 10-codeword system and begins with a Logic-1 synchronization pulse 42 and ends with an idle interval having a time of approximately 39 bits. Each frame 2, however, is transmitted at the end of the idle interval and begins with a synchronization-2 signal 46, which comprises three consecutive logical ones. At the end of the transmission of frame 2, there is another empty interval, followed by repeated transmissions of frames 1 and frame 2, each separated by an empty interval and each frame 2 beginning with a 3-bit synchronization signal 46.

Regardless of whether a 10 or 20 codeword format is used by a given transmitter, the codewords of the format must be accurately generated by the transmitter. The codeword sequence to be transmitted is stored in a memory in transmitters 24 and 26, whereas the codeword sequence transmitted by transmitter 25 is entered by a user through manipulation of pushbutton keys 27 (Fig. 1).

Figure 4 is a block diagram of a transmitter 24 which transmits pre-stored code words in ten code word format. In Figure 4, a transmitter unit 31 operates in accordance with signals from a timing generator 33 to read the ten permanently stored code words from a code word source 39 and convert them into RF signal pulses which are sent via an antenna 34 to the control unit 38 (Figure 1). The transmitter of Figure 4 is normally idle. When an operator wishes to transmit a code, the operator depresses a push button 36 to which the timing generator 33 responds by generating a continuous sequence of clock pulses at a rate of approximately one pulse per millisecond. The clock pulses are applied to the transmitter unit 31 via a line 37 and control the reading of the ten code words from the code word source 39 and their transmission in the ten code word format from the antenna 34. The code word source 39 is a memory which permanently stores the ten code words in the format shown in Table 1. To simplify the identification of the source of the transmitted code word sequences, the tenth code word stored by the code word source 39 is always a code character "A" as shown in Table 1.

In order to control the minimum number of repetitions with which the code sequence is transmitted, the timing generator 33 may include a delay device, such as a monostable multivibrator (not shown), which keeps the timing generator 33 operating for a predetermined period of time, independent of the time during which the push button 36 is actually depressed. Such preset operation of the timing generator 33 ensures that a minimum number of code word sequences are transmitted each time the button 36 is depressed.

Figure 5 is a block diagram representation of a transmitter 26 for transmitting 20 code word sequences of the type shown in Figure 3. A transmitter unit 51 responds to signals from a timing generator 53 to read permanently stored code words from a code word source 59 and convert them into RF signal pulses which are transmitted via an antenna 54 to the control unit 38 (Figure 1). The transmitter of Figure 5 is normally idle. When an operator wishes to transmit a code, the operator presses a push button 56, to which the timing generator 53 responds by generating a continuous sequence of clock pulses at a rate of approximately one pulse per millisecond. These clock pulses are applied to the transmitter unit 51 via a line 57 and control the reading and transmission of the code words. Figure 6 is a flow chart of the operation of the transmitter of Figure 5 and will be described in connection with the operation of the transmitter of Figure 5.

The sequence shown in Figure 6 begins at a block 60 with the detection of the closing of the push button 56. The pressing of the button 56 causes the time generator 53 to repeat a Sequence of clock pulses at a rate of one pulse per millisecond. In response to a first clock pulse, the transmitting unit 51 transmits a logic one, synchronization 1 signal having a duration of 1 bit (one millisecond) via the antenna 54. At this time, the transmitting unit 51 also begins reading code words from a code word source 59 via a communication path 58. In a block 64, the code words read from the code word source 59 are transmitted sequentially at a rate of one code word bit per clock pulse until the last bit of the tenth code word has been transmitted. At the end of the transmission of the tenth code word, the transmitting unit 51 interrupts all transmissions for a period of 39 bits (block 66).

The transmitter 51 terminates the idle interval by sending a synchronization 2 signal consisting of three consecutive logic ones (block 68). At the end of the transmission of the synchronization 2 signal, the code words 11 to 20 provided by the code word source 59 are transmitted in a manner substantially identical to the transmission of the code words 1 to 10. At the end of the transmission of the code words 11 to 20, the flow chart proceeds to a block 71 where another idle interval with a time of 39 bits is inserted and the flow returns to block 60 where a determination of the state of the push button 56 is made. If the push button 56 is still closed, the sequence 60 to 71 repeats itself. Since the time required to transmit both code word frames 1 and 2 and both blank intervals is only 182-bit time (182 milliseconds), normal human interaction with the push button 56 results in multiple transmissions of the entire 20-code word code sequence. To control the minimum number of repetitions with which the code sequence is transmitted, the timing generator 53 may include a delay device, such as a monostable multivibrator (not shown), which keeps the timing generator 53 operating for a predetermined period of time, regardless of the time during which the push button 56 is actually depressed. Such preset operation of the timing generator 53 ensures that the minimum number of code word sequences are transmitted each time the button 56 is depressed.

In the present embodiment, the codeword source 59 comprises a memory which stores the 4-bit codes of the type shown in Table 1. Since in the present embodiment twenty 3-state codewords are used, there are more than 3 billion possible codewords. With such a large number of possible codes, it can be guaranteed that the codeword sequences of all transmitters are truly different.

The touch pad transmitter 25 shown in the block diagram of Figure 7 does not involve long-term storage of a security code, but rather briefly stores ten code words derived from pressing numeric keys 27 four times. The stored code words are transmitted when a transmit key 61 is pressed within a short period of time (10 to 20 seconds) after the first numeric key is pressed. If the four code keys and the transmit key are not pressed within the short period of time, the stored code words are rendered inaccessible (erased) so that no one who finds the touch pad transmitter or thief can use information stored in the transmitter to gain access to a protected gate. The time of code word storage, i.e. 10 to 20 seconds, is kept short in order to allow slightly more time than necessary for a slow operator to enter and transmit a code sequence.

The transmitter 25 shown in Figure 7 is now used in conjunction with the flow chart of Figure 8. The transmitter 25 includes a keypad unit 60 having ten numeric keys 27 and a transmit key 61. The transmitter of Figure 7 normally waits for a numeric key to be pressed, and in this wait mode (block 130, Figure 8), only the keypad unit 60 receives power. When a keypad numeric key 27 is pressed, a signal is sent over a line 62 to a power switch 63 which then powers a light 65, a control unit 66, and an RF transmitter 67 over a line 64. The light 65, which may comprise a plurality of light emitting diodes, produces light when it receives power on the line 64 to indicate to the operator that at least a portion of the security code sequence is stored in the transmitter 25. The keypad unit 60 further responds to the depression of a numeric key 27 by transmitting a four-digit binary code representation of the particular key pressed to the controller 66 via a communication path 68. The four-digit binary code, which consists of all zeros, is not used to represent a key so that all numeric key representations include at least a single logical 1.

When controller 66 receives a representation of a first key press from communication path 68, it proceeds to block 131 where a ten second timer T10 is started. Controller 66 further encodes the received key press representation into the format of Table 1 in preparation for transmission to controller 38. Each keypad entered code consists of four key presses. Each of the four key press representations of a keypad entered code is encoded by controller 66 into two code words for a total of eight code words as shown in Table 2. TABLE 2 Received keystroke stored code words The ninth code word is then selected according to Table 3. TABLE 3 9. Code word If key 0 is not pressed Key 0 is pressed and key 9 is not pressed Key 0 and key 9 are pressed

The tenth stored code word is selected at manufacture for all keypad type transmitter code word sequences to be one of the words "B" or "C", i.e. some keypad transmitters 25 will always store a code word "B" as the tenth code word and other test field transmitters will always store a code word "C" as the tenth code word. However, no keypad transmitter 25 will store a code word "A" as the tenth code word.

Since each keystroke is reproduced by the control device 66 is received, it is encoded and stored (block 132, Figure 8) until 10 code words are stored. The operator, after completing the pressing of the four keys 27 of the keypad for a code, presses the transmit key 61, causing a transmit signal to be sent over a line 69 to the controller 66. The storage of the code words and the reception of a transmit signal are regulated by the previously set timer T₁₀ (block 133). If within approximately 10 seconds of setting the timer T₁₀ the ten code words are not stored and the transmit signal is not received, then the flow advances from block 133 to a block 134 where timers such as timer T₁₀ are cleared and the stored code words are made inaccessible (deleted). After block 134, the controller 66 sends a signal (block 140) on a line 70 (Figure 7), to which signal the power switch 63 responds by removing the power supply from the conductor 64.

If the transmit signal on line 69 is received within ten seconds of starting timer T₁₀ (block 135) and all ten code words are stored, then controller 66 sends (block 136) the stored code words to RF transmitter 67, which transmits them to controller 38 via antenna 71. At this time, a timer T₂₀ is started (block 137). Whenever transmit button 71 is pressed within 20 seconds of starting timer T₂₀ (block 138), the code word sequence is retransmitted (block 136) and timer T₂₀ is re-started (block 137). If more than 20 seconds pass after the starting or restarting of the timer T₂₀, the confirmation branch of a timer loop 139 is entered and the stored code words are made inaccessible (block 134) and the power is switched off (block 140)

The three types of transmitters 24 (Figure 4), 25 (Figure 7) and 26 (Figure 5) each transmit a gate opening signal which identifies the type of transmitter sending the request. The transmitter 26 transmits in the 20 code word format (Figure 3) which can be identified by the synchronization 2 signal 46. The transmitter 24 transmits in the 10 code word format (Figure 2) and identifies its type by the fact that the code word 10 is always a code character "A" (Table 1). The transmitter 25 also transmits in the 10 code word format and identifies its type by the fact that the code word 10 is always a character "B" or "C" (Table 1) and never a code character "A".

The code word sequences transmitted by the transmitters of Figures 4, 5 and 7 are received by an antenna 74 of the control unit 38 (Figure 9) and provided to an RF receiver 73. The receiver 73 provides the received signals to a decoder 76 which converts them into the binary format shown in Table 1 and applies them to a receiver controller 78. The controller 78 identifies the transmitter type and compares the received codes with approved codes stored in a memory 79 for the type of transmitter received. If a match is found, the controller 78 operates the gate device 11 via conductor 18. The codes stored in the memory 79 for each type of transmitter are recorded therein during a receiver programming mode which is initiated by pressing a program switch pushbutton 84.

The control unit 38 further comprises a safety switch 83 which is connected to the control device 78 and is used to modify the response of the control device 78 to received codes. When the safety switch 83 is in a first position, the control device responds 78 responds to received codes from all types of transmitters 24, 25 and 26 and generates actuation signals on line 18 when matching security codes occur. However, when security switch 83 is in a second position, controller 78 responds only to received code sequences from touch pad transmitters 25. Thus, security switch 83 enables the owner of the system to control which type of transmitter can operate the gate. For example, if a stored code type transmitter (24, 26) is lost or stolen, the owner can place security switch 83 in the second position and thereby allow access only to those persons who know the appropriate touch pad code.

Depressing the program switch 84 places the controller 78 in the programming mode shown in the flow chart of Figure 10. In the programming mode, the transmitter(s) to be used with the receiver can be individually enabled to send their respective security codes to the controller 38, which receives these security codes and stores them as valid codes in the memory 79. When the program switch 84 is initially depressed, the controller 78 enters block 86 (Figure 10) where it awaits receipt of a first frame 1 of code words from the decoder 76. The controller 78 determines in block 86 that a frame 1 has been received by analyzing the number of bits in the received synchronization signal. It should be noted that either a frame 1 of the 20 code word format (Figure 3) or any frame of the 10 code word format (Figure 2) is determined to be a frame 1 in block 86. If no frame 1 is received within a time period predetermined in block 80, the controller exits the program mode and returns to a mode in which it waits for the arrival of a code for gate operation purposes. If 3 bits are received in block 86 as the synchronization signal, a frame 2 has actually been received and the sequence goes back to the beginning to wait for a frame 1.

If a frame 1 has been received in block 86, then the ten code words of the frame are stored in a block 90 and the immediately following frame is stored in a block 92. After a next frame is received in block 92, the sequence proceeds to a block 94 to determine whether the synchronization signal received in block 92 comprises a single logic one. If the received synchronization signal comprises a single logic one, then a 10-codeword sequence has been received and the sequence proceeds to a block 96. In block 96, the codeword 10 is checked to identify whether the incoming code sequence is from the stored code type transmitter 24 (Figure 4) in which the codeword 10 is equal to the code character 1A" (Table 1), or from the touch panel type transmitter 25 (Figure 7) in which the codeword 10 is not equal to the code character "A". If block 96 determines that the codeword 10 is not equal to the code character "A", then the sequence proceeds to a block 97 where the 10-codeword sequence is stored in a location Y of the memory 79, which location allows 10-codeword sequences of keypad type transmitters 25. Alternatively, if block 96 determines that code word 10 equals code character "A", the sequence proceeds to a block 98 where the received 10 code word sequence is stored in a location X of memory 79 which is associated with permitted 10 code word sequences from transmitters of the stored code type. After storing the received 10 code word sequence in either step 97 or 98, control unit 78 exits program mode.

If the processing of block 94 indicates that the received synchronization signal does not contain a single logical one, a block 95 is performed to determine if the synchronization signal comprises 3 logical ones. A synchronization code of three logical ones indicates the reception of a frame 2 of code words 11 through 20. If the received synchronization signal does not comprise three logical ones, the program mode is exited. However, if block 95 determines that the synchronization signal comprises three logical ones, the code word sequence comprising the ten code words 1 through 10 which was held in block 90 and the newly received ten code words 11 through 20 are stored (block 99) in a location Z of memory 79 which is allocated for storing authorized twenty code word sequences. After storing (block 99) the two frame code word sequence in memory 79, the program mode is exited again.

Repeatedly entering the program mode with different transmitters allows a number of possible permitted code words to be stored in the memory 79. The present embodiment allows for the storage of one ten code word sequence of the stored code type transmitter, one ten code word sequence of the touch pad type transmitter, and four twenty code word sequences.

It should be noted that Figure 10 only shows the reception of the code sequences before they are stored in the memory 79. It may be desirable to require that an incoming code sequence be repeated several times before it is stored as a valid sequence. An arrangement for requiring several valid code sequences in a substantially similar environment is described in detail in the previously mentioned patent to C. Heitschel et al.

Figure 10 is a flow chart of the normal operation of the Controller 78 of Figure 9 in which controller 78 waits for the arrival of the code sequence for possible gate actuation. This mode begins at a block 100 in which a valid frame is awaited. If a valid frame 1 is received in block 100, the sequence proceeds to a block 102 in which the 10 received code words are temporarily stored and the sequence proceeds to a block 103 which waits for the next received frame. A block 105 is performed after a next frame is received to determine whether the received frame is frame 2 or a second occurrence of frame 1. The discrimination is made by evaluating the length of the synchronization signal. If the synchronization signal in block 105 indicates that a frame 2 has been received, the code words held in block 102 are read in block 107 and the twenty code words forming the received frames 1 and 2 are compared (block 109) with the approved twenty code word sequences stored in location Z of memory 79. Matches between the received 20 code word sequences and the stored approved 20 code word sequences are indicated in block 111. If block 111 determines that the received 20 code word sequence does not match a stored approved 20 code word sequence, control passes back to block 100 to await the reception of a new frame 1. Alternatively, if a match is determined between the received 20 code word sequence and a stored permitted 20 code word sequence in block 111, the sequence proceeds to a block 112 where the state of the safety switch 83 is checked. If the safety switch 83 is in its second position (called position 2), indicating that only touch pad type codes are permitted to open the gate, then the sequence proceeds from block 112 to block 100 to wait for the receipt of a new frame 1. In normal However, during operation, the safety switch 83 will be in its first position, indicating that all types of codes are permitted to open the gate. If block 112 determines that the safety switch is in the first position (not position 2), then the sequence goes to block 113 where an actuation signal is generated to open the gate. After generating the actuation signal, the sequence goes to block 100 to wait for the receipt of a new frame 1.

If block 105 determines that a second frame 1 has been received after a first frame 1, then the tenth code word of the received 10 code word sequence is checked in block 106 to determine whether the received code word sequence has a tenth code word equal to the character "A" (Table 1), indicating a transmitter 24 of the stored code type, or whether a tenth code word is equal to the characters "B" or "C" (Table 1), indicating a keypad type transmitter 25. If a keypad type code is identified in block 106, then the received code is compared to the approved keypad code stored in location Y of memory 79 (block 116). If the codes match (block 118), then the sequence proceeds to block 113 where an actuation signal is generated. The sequence proceeds from block 118 to block 100 if no match is found in block 118. If block 106 determines that the received ten code word sequence is from a stored code transmitter 24, then the ten code words of received frame 1 are compared (block 115) with the ten code word sequence stored in location X of memory 79. If the compared code sequences do not match (block 117), then the sequence proceeds to block 100. Alternatively, if block 117 determines that the compared code sequences match, the sequence goes to a block 119 where the position of the safety switch 83 is checked. If the safety switch 83 is in position 2, the sequence goes to block 100. Alternatively, if block 119 determines that the safety switch is in position 1, indicating acceptance of all types of incoming codes, the sequence goes to block 113 where an actuation signal is generated.

In the flow chart of Figure 11, the state of the safety switch 83 is checked in blocks 112 and 119 immediately before the step of generating the actuation signal. The placement of the comparison provided by blocks 112 and 119 can be moved to other locations within the flow chart of Figure 11 without departing from the present invention. In fact, the flow chart of Figure 11 could be implemented as two separate flow charts, one operating when the safety switch 83 is in position 1 and the other operating when the safety switch 83 is in position 2. In the previous embodiment, a two-position safety switch is used to indicate the response of the controller. A third position of the safety switch or an additional lockout switch (not shown) may be used to prevent the control unit 38 from responding to all received door opening request signals, regardless of their source.

Although preferred embodiments of the invention have been shown, it will be apparent to those skilled in the art that various modifications and changes can be made thereto without departing from the scope of the invention as defined in the appended claims.

Claims (7)

1. Garage door remote opening system (10) for selectively opening a door (17), comprising: - at least one touchpad transmitter (25) with a plurality of buttons (27, 61) for sending touchpad-type door opening request signals comprising a touchpad-type security code word sequence, - at least one transmitter (24, 26) with stored code, comprising a code word sequence stored in a long-term memory (39) for transmitting gate opening request signals of the stored code type, comprising the stored code word sequence (41), wherein the gate opening request signals of the stored code type are distinguishable from the touch panel type gate opening request signals; - means (73, 74) for receiving the gate opening request signals of the touch panel type and for receiving the gate opening request signals of the stored code type, - safety control means (83) responsive to operator action for selectively generating either a first signal indicating door opening in response to both the touch panel type door opening request signals and the stored code type door opening request signals, or a second signal indicating door opening in response to the touch panel type door opening request signals only. Type gate opening request signals, and - gate actuation signal generating means (78) responsive to a received gate opening request signal for determining the type of received gate opening request signal and for selectively generating gate opening control signals in response to the received gate opening request signals of both the touch pad type and the stored code type when the security control means (83) generates the first signal. 2. A system according to claim 1, wherein the gate actuation signal generating means comprises - means (79) for storing at least one approved keypad type security code sequence and at least one approved security code sequence of the stored code type, - means (78) for comparing a received touchpad type security code sequence only with the at least one stored approved touchpad type security code sequence, and - means (78) for comparing a received security code sequence of the stored code type only with the at least one stored permitted security code sequence of the stored code type. 3. A system according to claim 2, wherein the gate actuation signal generating means (78) in a learning mode thereof comprises means (78) for writing at least one approved keypad type security code sequence and at least one approved security code sequence of the stored code type into the storage means (79). 4. The system of claim 1, wherein both the keypad type security code sequence (41) and the security code sequence of the stored code type comprise the same predetermined number of code words and the means for determining the type of received gate opening request comprises means for analyzing a predetermined code word of each received gate opening request. 5. The system of claim 1, wherein the safety control means (83) is responsive to operator intervention for generating a third signal and the gate actuation signal generating means (78) responds to the third signal by inhibiting opening of the gate in response to all types of received gate opening request signals. 6. A method of operating a garage door opening device (11) for selectively generating actuation signals in response to touch pad type security code sequences and security code sequences of the stored code type, the method comprising: - storing at least one keypad type security code sequence in the device (11), - storing at least one security code sequence of the stored code type in the device, - receiving a transmitted security code sequence which includes indications of its type, - identifying the type of security code sequence received, - in response to the identifying step, comparing the received security code sequence only with the at least one of the stored approved security code sequences of the same type, and - providing safety control means (83) responsive to operator intervention for selectively generating either a first signal indicating door opening in response to both the touch pad type door opening request signals and the stored code type door opening request signals, or a second signal indicating door opening in response to only which displays touch panel type gate opening request signals, and - generating actuation signals if the received security code sequence matches a stored security code sequence compared with it in the comparison step. 7. The method of claim 6 comprising: - generating a security control signal which indicates a gate actuation only in response to received touch pad type security code sequences, and wherein the step of generating actuation signals comprises - generating actuation signals only in response to received touch pad type security code sequences, when the security control signals have been generated.