Adapter for on-vehicle navigation system

Abstract

To execute control for allowing an on-vehicle navigation system to display video during driving of a vehicle while reflecting an estimated drive distance.SOLUTION: In an adapter 1, a pulse control section 20 sets a period of a vehicle speed pulse signal transmitted during a first period on the basis of the difference between a first estimated drive distance as a drive distance of a vehicle specified by vehicle information and a second estimated drive distance as a drive distance estimated by a vehicle speed pulse signal given to an on-vehicle navigation system 104 by the adapter 1, and transmits a vehicle speed pulse signal with the set period to the on-vehicle navigation system 104.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to an adapter for an in-vehicle navigation system. [Background technology]

[0002] Patent Document 1 discloses an adapter for an in-vehicle navigation system. The adapter in Patent Document 1 is an adapter for providing a vehicle speed pulse signal to a navigation system mounted on a vehicle. The navigation system has a function of becoming ineffective a predetermined time after detecting a pulse in a received vehicle speed pulse signal. The adapter alternates between a first period during which the vehicle speed pulse signal is transmitted to the navigation system and a second period during which the vehicle speed pulse signal is not transmitted. The length of the first period is shorter than the predetermined time. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 7274798 Summary of the Invention [Problem to be solved by the invention]

[0004] By using the adapter of Patent Document 1, it is possible to cause an in-vehicle navigation system having a predetermined function of disabling the television display a predetermined time after the detection of a pulse to display images on a television or the like while driving. However, since the adapter of Patent Document 1 determines the period of the vehicle speed pulse signal to be transmitted in the next first period based only on the number and period of the vehicle speed pulse signal detected in the second period (period in which the vehicle speed pulse signal is not transmitted), the distance actually traveled by the vehicle and the distance traveled by the vehicle recognized by the in-vehicle navigation system are likely to differ.

[0005] One object of the present disclosure is to provide a technology that can execute control that enables an in-vehicle navigation system to display images while the vehicle is traveling, while reflecting an estimated travel distance. [Means for solving the problem]

[0006] The adapter for an in-vehicle navigation system according to the present disclosure includes: An adapter for providing a vehicle speed pulse signal to an in-vehicle navigation system mounted in a vehicle, comprising: The in-vehicle navigation system includes a display system having a display device and a control device that causes the display device to display an image based on a video signal, the display system disables the image display based on the video signal when a state in which the vehicle speed pulse signal input to the in-vehicle navigation system has a change while the image display based on the video signal is enabled continues for a period longer than a first reference time, and enables the image display based on the video signal when a state in which the vehicle speed pulse signal input to the in-vehicle navigation system has no change while the image display based on the video signal is disabled continues for a period longer than a second reference time, and the second reference time is set longer than the first reference time; The adapter comprises: a receiving unit that receives vehicle information including at least one of vehicle speed information and travel distance information from an external device provided outside the adapter in the vehicle; a pulse control unit that generates a vehicle speed pulse signal based on the vehicle information and transmits the vehicle speed pulse signal to the in-vehicle navigation system; having The pulse control unit is a first period during which the vehicle speed pulse signal in a changed state is transmitted and a second period during which the vehicle speed pulse signal in a non-changed state is transmitted are alternately repeated, the length of the first period is made shorter than the first reference time, and the length of the second period is made longer than the second reference time; The period of the vehicle speed pulse signal to be transmitted during the first period is set based on the difference between a first estimated traveling distance, which is the traveling distance of the vehicle specified by the vehicle information, and a second estimated traveling distance, which is the traveling distance of the vehicle estimated by the vehicle speed pulse signal provided by the adapter to the in-vehicle navigation system.

[0007] The adapter for an in-vehicle navigation system according to the present disclosure includes: An adapter for providing a vehicle speed pulse signal to an in-vehicle navigation system mounted in a vehicle, comprising: The in-vehicle navigation system includes a display system having a display device and a control device that causes the display device to display an image based on a video signal, the display system disables the image display based on the video signal when a state in which the vehicle speed pulse signal input to the in-vehicle navigation system has a change while the image display based on the video signal is enabled continues for a period longer than a first reference time, and enables the image display based on the video signal when a state in which the vehicle speed pulse signal input to the in-vehicle navigation system has no change while the image display based on the video signal is disabled continues for a period longer than a second reference time, and the second reference time is set longer than the first reference time; The adapter comprises: a signal input unit to which a vehicle speed pulse signal is input as vehicle information from an external device provided outside the adapter in the vehicle; a pulse control unit that generates a vehicle speed pulse signal based on the vehicle information and transmits the vehicle speed pulse signal to the in-vehicle navigation system; having The pulse control unit is a first period during which the vehicle speed pulse signal in a changed state is transmitted and a second period during which the vehicle speed pulse signal in a non-changed state is transmitted are alternately repeated, the length of the first period is made shorter than the first reference time, and the length of the second period is made longer than the second reference time; The period of the vehicle speed pulse signal to be transmitted during the first period is set based on the difference between a first estimated traveling distance, which is the traveling distance of the vehicle specified by the vehicle information, and a second estimated traveling distance, which is the traveling distance of the vehicle estimated by the vehicle speed pulse signal provided by the adapter to the in-vehicle navigation system.

[0008] The adapter for an in-vehicle navigation system according to the present disclosure includes: An adapter for providing a CAN signal to an in-vehicle navigation system installed in a vehicle, The in-vehicle navigation system includes a display system having a display device, a control device that causes the display device to display an image based on a video signal, and a communication unit that can receive the CAN signal; the display system disables the video display based on the video signal when the state of the signal input to the communication unit while the video display based on the video signal is enabled continues longer than a first reference time in the state of the CAN signal indicating that the vehicle is moving, and enables the video display based on the video signal when the state of the signal input to the communication unit while the video display based on the video signal is disabled continues longer than a second reference time in the state of the signal indicating that the vehicle is stopped, and the second reference time is set longer than the first reference time; The adapter comprises: a receiving unit that receives vehicle information including at least one of vehicle speed information and travel distance information from an external device provided outside the adapter in the vehicle; a signal control unit that generates the CAN signal based on the vehicle information and transmits the CAN signal to the communication unit; having the signal control unit alternately repeats a first period during which the state of the signal provided to the communication unit is maintained in the state of the CAN signal indicating that the vehicle is traveling and a second period during which the state of the signal of the communication unit is maintained in the state indicating that the vehicle is stopped, and sets a length of the first period to be shorter than the first reference time and sets a length of the second period to be longer than the second reference time; An estimated mileage estimated based on the vehicle information last acquired in the second period or the vehicle information acquired in the first period is calculated by calculation, and the CAN signal including vehicle speed data or mileage data based on the estimated mileage calculated by calculation is transmitted to the communication unit during the first period. Effect of the Invention

[0009] According to the technology disclosed herein, it is possible to execute control that enables an in-vehicle navigation system to display images while the vehicle is traveling, while reflecting an estimated travel distance. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a block diagram conceptually showing an in-vehicle system including an adapter for an in-vehicle navigation system according to the first embodiment. [Diagram 2] FIG. 2A is a waveform diagram illustrating a vehicle speed pulse signal in a simplified manner, and FIG. 2B is an explanatory diagram illustrating an enlarged portion of the vehicle speed pulse signal. [Diagram 3] FIG. 3 is an explanatory diagram for explaining the timing of data acquisition, the state of a first period, the state of a second period, etc., in the adapter for the in-vehicle navigation system according to the first embodiment. [Figure 4] FIG. 4 is an explanatory diagram for explaining a part of FIG. 3 in detail on an enlarged scale. [Diagram 5] FIG. 5 is a block diagram conceptually showing an in-vehicle system including an adapter for an in-vehicle navigation system according to the second embodiment. [Figure 6] FIG. 6 is a block diagram conceptually showing an in-vehicle system including an adapter for an in-vehicle navigation system according to the third embodiment. [Figure 7] FIG. 7 is an explanatory diagram for explaining the timing of data acquisition, the state of the first period, the state of the second period, etc., in the adapter for the in-vehicle navigation system according to the third embodiment. [Figure 8] FIG. 8 is a block diagram conceptually showing an in-vehicle system including an adapter for an in-vehicle navigation system according to the fourth embodiment. [Figure 9] FIG. 9 is a block diagram conceptually showing an in-vehicle system including an adapter for an in-vehicle navigation system according to the fifth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Each of the following [1] to [7] is an example of a characteristic technique included in this disclosure.

[0012] [1] An adapter for providing a vehicle speed pulse signal to an in-vehicle navigation system mounted in a vehicle, The in-vehicle navigation system includes a display system having a display device and a control device that causes the display device to display an image based on a video signal, the display system disables the image display based on the video signal when a state in which the vehicle speed pulse signal input to the in-vehicle navigation system has a change while the image display based on the video signal is enabled continues for a period longer than a first reference time, and enables the image display based on the video signal when a state in which the vehicle speed pulse signal input to the in-vehicle navigation system has no change while the image display based on the video signal is disabled continues for a period longer than a second reference time, and the second reference time is set longer than the first reference time; The adapter comprises: a receiving unit that receives vehicle information including at least one of vehicle speed information and travel distance information from an external device provided outside the adapter in the vehicle; a pulse control unit that generates a vehicle speed pulse signal based on the vehicle information and transmits the vehicle speed pulse signal to the in-vehicle navigation system; having The pulse control unit is a first period during which the vehicle speed pulse signal in a changed state is transmitted and a second period during which the vehicle speed pulse signal in a non-changed state is transmitted are alternately repeated, the length of the first period is made shorter than the first reference time, and the length of the second period is made longer than the second reference time; A period of the vehicle speed pulse signal to be transmitted during the first period is set based on a difference between a first estimated travel distance, which is a travel distance of the vehicle specified by the vehicle information, and a second estimated travel distance, which is a travel distance of the vehicle estimated by a vehicle speed pulse signal provided by the adapter to the in-vehicle navigation system. Adapter for car navigation systems.

[0013] The adapter of [1] above can alternately repeat the first period and the second period so that the first period during which the vehicle speed pulse signal in a changed state is shorter than the first reference time, and the second period during which the vehicle speed pulse signal in an unchanged state is longer than the second reference time. That is, when the image display based on the image signal is valid during the vehicle running, the adapter can output the vehicle speed pulse signal in a changed state during the first period, and can switch to the vehicle speed pulse signal in an unchanged state before the image display is invalidated. The adapter can output the vehicle speed pulse signal in an unchanged state during the second period, and since such first and second periods are alternately repeated, the in-vehicle navigation system to which the vehicle speed pulse signal is transmitted from the adapter can maintain the valid state of the image display. Furthermore, when the adapter of [1] sets the period of the pulse signal to be transmitted in the first period, it sets the period of the pulse signal to be transmitted in the first period based on the difference between a first estimated mileage, which is the mileage of the vehicle specified by the vehicle information, and a second estimated mileage, which is the mileage estimated by the pulse signal provided by the adapter to the in-vehicle navigation system. Therefore, this adapter can execute control that can enable the in-vehicle navigation system to display an image while the vehicle is traveling, while reflecting the difference between the actual mileage of the vehicle and the mileage of the vehicle recognized by the in-vehicle navigation system.

[0014] For example, the adapter of Patent Document 1 counts the number of pulses of the vehicle speed pulse signal received in the second period, and provides the vehicle speed pulse to the navigation system so that the number of pulses c×(a+b) / b is transmitted in the first period based on the number of pulses c obtained in the second period, the length a of the first period, and the length b of the second period. This method is effective to a certain extent when the length of one pulse of the vehicle speed pulse signal is sufficiently short compared to the length of the second period, but when the length of one pulse of the vehicle speed pulse signal is approximately the same as the length of the second period or longer than the length of the second period, an error occurs between the actual travel distance of the vehicle and the estimated travel distance estimated by the vehicle speed pulse signal provided by the adapter to the navigation system. For example, when the vehicle is traveling at such a low speed that the length of one pulse of the vehicle speed pulse signal is longer than the length of the second period, the adapter is likely to count the number of pulses of the vehicle speed pulse signal received in the second period as 0. If the number of pulses is counted as 0 in this way, the adapter will consider the vehicle to be in a stopped state even though the vehicle is actually moving at a low speed, and will not output a vehicle speed pulse in the first period. As another example, when the length of the second period is about 1.5 times the length of one pulse of the vehicle speed pulse signal received in the second period, it is possible to round down the pulses received in the second period that are less than one pulse. In this case, the adapter counts the number of pulses c received in the second period as 1, which does not accurately reflect the distance traveled by the vehicle in the second period. In this case, the number of pulses calculated by the formula c×(a+b) / b differs from the number of pulses actually generated by the vehicle in the second period and the first period, which results in an error between the travel distance of the vehicle recognized by the navigation system (estimated travel distance estimated by the obtained vehicle speed pulse signal) and the actual travel distance of the vehicle. Even if a method of rounding up pulses that are less than one pulse is adopted, the number of pulses c in the second period will be counted as 2, which does not accurately reflect the distance traveled by the vehicle in the second period, and the same problem will occur.In this way, an error due to the resolution occurs in each first period, and the error accumulates each time the first period arrives. Therefore, in a navigation system that provides a vehicle speed pulse signal in this manner, the actual travel distance of the vehicle and the estimated travel distance estimated by the vehicle speed pulse signal received by the navigation system will differ greatly. In contrast, the adapter in [1] above can set the period of the vehicle speed pulse signal in a manner that reflects the difference between the first estimated travel distance from a predetermined reference time point and the second estimated travel distance from the reference time point, and if the period of the vehicle speed pulse signal can be set in a direction that makes it difficult to cause a "deviation" caused by this difference, the in-vehicle navigation system can more accurately grasp the travel distance of the vehicle. In particular, the adapter in [1] above can set the period appropriately by reflecting the above difference each time the second estimated travel distance is calculated, so that the problem of the adapter in Patent Document 1 (the problem of the "deviation" becoming large due to the accumulation of errors caused by the resolution each time the first period arrives) does not occur.

[0015] [2] An adapter for providing a vehicle speed pulse signal to an in-vehicle navigation system mounted in a vehicle, The in-vehicle navigation system includes a display system having a display device and a control device that causes the display device to display an image based on a video signal, the display system disables the image display based on the video signal when a state in which the vehicle speed pulse signal input to the in-vehicle navigation system has a change while the image display based on the video signal is enabled continues for a period longer than a first reference time, and enables the image display based on the video signal when a state in which the vehicle speed pulse signal input to the in-vehicle navigation system has no change while the image display based on the video signal is disabled continues for a period longer than a second reference time, and the second reference time is set longer than the first reference time; The adapter comprises: a signal input unit to which a vehicle speed pulse signal is input as vehicle information from an external device provided outside the adapter in the vehicle; a pulse control unit that generates a vehicle speed pulse signal based on the vehicle information and transmits the vehicle speed pulse signal to the in-vehicle navigation system; having The pulse control unit is a first period during which the vehicle speed pulse signal in a changed state is transmitted and a second period during which the vehicle speed pulse signal in a non-changed state is transmitted are alternately repeated, the length of the first period is made shorter than the first reference time, and the length of the second period is made longer than the second reference time; A period of the vehicle speed pulse signal to be transmitted during the first period is set based on a difference between a first estimated travel distance, which is a travel distance of the vehicle specified by the vehicle information, and a second estimated travel distance, which is a travel distance of the vehicle estimated by a vehicle speed pulse signal provided by the adapter to the in-vehicle navigation system. Adapter for car navigation systems.

[0016] The adapter [2] above can achieve the same effects as the adapter [1] above.

[0017] [3] The pulse control unit sets a period of the vehicle speed pulse signal to be transmitted during the first period based on the first estimated travel distance specified by each of the vehicle information when the vehicle information is received during each of the second period and the first period. An adapter for an in-vehicle navigation system according to [1] or [2].

[0018] The adapter [3] above can set the period of the vehicle speed pulse signal to be transmitted in the first period, reflecting not only the first estimated mileage identified in the vehicle information received in the second period, but also the second estimated mileage identified in the vehicle information received in the first period.

[0019] [4] The external device includes a CAN communication line; The vehicle transmits the vehicle information via the CAN communication line, The receiving unit receives the vehicle information from the CAN communication line. An adapter for an in-vehicle navigation system according to [1] or [3].

[0020] The adapter of Patent Document 1 must always use a vehicle speed pulse signal received from outside the adapter when generating a vehicle speed pulse signal for the first period, and cannot generate a new vehicle speed pulse signal without using a vehicle speed pulse signal generated outside the adapter. In this respect, the adapter has room for improvement. In contrast, the adapter in [4] above can receive vehicle information from the vehicle's CAN communication line and generate a new vehicle speed pulse signal based on this vehicle information. For example, since a vehicle speed pulse is generated when the wheels rotate to a certain degree, if the vehicle speed is very slow, it takes a very long time for one pulse to be generated before the next pulse is generated. For this reason, there is a concern that the vehicle speed cannot be grasped in real time for a long period of time between pulses. On the other hand, in the method of receiving vehicle information from the CAN communication line, if the ECU or the like outputs vehicle information to the CAN communication line at short intervals and the adapter can monitor this vehicle information, it will be possible to obtain vehicle information at short intervals regardless of the vehicle speed, even if the vehicle speed is very slow.

[0021] [5] The second estimated travel distance is a travel distance from a reference time point that is determined based on the number of pulses of a vehicle speed pulse signal provided to the in-vehicle navigation system from the reference time point and a travel distance per pulse, The pulse control unit sets a period of the vehicle speed pulse signal to be transmitted during the first period based on a difference between the first estimated travel distance from the reference time point and the second estimated travel distance from the reference time point. An adapter for an in-vehicle navigation system according to any one of [1] to [4].

[0022] The adapter of [5] above can determine a certain point in time as a reference point in time, and can more accurately calculate a second estimated mileage from the reference point in time to the point in time when the pulse was last output. Then, the adapter can set the period of the vehicle speed pulse signal in a manner that reflects the difference between the first estimated mileage from the reference point in time and the second estimated mileage from the reference point in time.

[0023] [6] A switching unit is provided which switches between a first state in which a vehicle speed pulse signal generated by the pulse control unit is input to the in-vehicle navigation system without inputting a vehicle speed pulse signal generated by the vehicle to the in-vehicle navigation system, and a second state in which a vehicle speed pulse signal generated by the vehicle is directly input to the in-vehicle navigation system without inputting a vehicle speed pulse signal generated by the pulse control unit to the in-vehicle navigation system. An adapter for an in-vehicle navigation system according to any one of [1] to [5].

[0024] The adapter [6] above can be switched between a state in which a vehicle speed pulse signal generated by the vehicle outside the adapter is input to the in-vehicle navigation system without inputting a vehicle speed pulse signal generated by the pulse control unit to the in-vehicle navigation system, and a state in which a vehicle speed pulse signal generated by the vehicle outside the adapter is directly input to the in-vehicle navigation system without inputting a vehicle speed pulse signal generated by the pulse control unit to the in-vehicle navigation system.

[0025] [7] An adapter for providing a CAN signal to an in-vehicle navigation system mounted in a vehicle, The in-vehicle navigation system includes a display system having a display device, a control device that causes the display device to display an image based on a video signal, and a communication unit that can receive the CAN signal; the display system disables the video display based on the video signal when the state of the signal input to the communication unit while the video display based on the video signal is enabled continues longer than a first reference time in the state of the CAN signal indicating that the vehicle is moving, and enables the video display based on the video signal when the state of the signal input to the communication unit while the video display based on the video signal is disabled continues longer than a second reference time in the state of the signal indicating that the vehicle is stopped, and the second reference time is set longer than the first reference time; The adapter comprises: a receiving unit that receives vehicle information including at least one of vehicle speed information and travel distance information from an external device provided outside the adapter in the vehicle; a signal control unit that generates the CAN signal based on the vehicle information and transmits the CAN signal to the communication unit; having the signal control unit alternately repeats a first period during which the state of the signal provided to the communication unit is maintained in the state of the CAN signal indicating that the vehicle is traveling and a second period during which the state of the signal of the communication unit is maintained in the state indicating that the vehicle is stopped, and sets a length of the first period to be shorter than the first reference time and sets a length of the second period to be longer than the second reference time; An estimated mileage estimated based on the vehicle information last acquired in the second period or the vehicle information acquired in the first period is calculated by a calculation, and the CAN signal including vehicle speed data or mileage data based on the estimated mileage calculated by the calculation is transmitted to the communication unit during the first period. Adapter for car navigation systems.

[0026] The adapter [7] above can execute control that enables the in-vehicle navigation system to display images while the vehicle is traveling, while reflecting the estimated travel distance.

[0027] First Embodiment The following description relates to the first embodiment. 1. Overview of the in-vehicle system 102 FIG. 1 conceptually illustrates an in-vehicle system 102 installed in a vehicle 100 . The in-vehicle system 102 is a system mounted on the vehicle 100, and is a system capable of performing various calculations, various controls, various operations, etc. within the vehicle 100. The vehicle 100 may be any type of vehicle, such as a gasoline vehicle, a hybrid vehicle, an electric vehicle, or a fuel cell vehicle.

[0028] The in-vehicle system 102 is provided with a large number of devices, and these devices are electrically connected to wiring for supplying power and communication lines for transmitting information. In the example of Fig. 1, the in-vehicle system 102 includes an in-vehicle navigation system 104, an electronic control unit 180 (hereinafter also referred to as ECU 180), a vehicle speed pulse signal generating source 170, a communication line 140, and the like, and although not shown, various devices and wiring other than those shown in Fig. 1 are also provided. The electronic control unit 180 may be composed of multiple types of ECUs. The ECU 180 and the communication line 140 correspond to examples of external devices.

[0029] The communication line 140 is a communication line that enables digital signals to be transmitted in the vehicle 100 according to a predetermined communication protocol. In a representative example described below, the communication line 140 functions as a serial communication bus that can transmit digital signals by serial communication. Specifically, the communication line 140 is configured as, for example, a CAN-BUS, and functions as a CAN communication line that performs communication according to the CAN (Controller Area Network) protocol. Electronic devices connected to the communication line 140 in the vehicle 100 are capable of communicating information with each other via the communication line 140.

[0030] The vehicle 100 is configured to transmit vehicle information through the communication line 140. For example, the ECU 180 may operate to continuously detect the speed of the vehicle 100 by a known method and transmit vehicle speed information including the most recent vehicle speed value to the communication line 140 at a predetermined time interval. Alternatively, the ECU 180 may operate to continuously detect the total mileage of the vehicle 100 by a known method and transmit mileage information including the most recent total mileage value to the communication line 140 at a predetermined time interval. The vehicle speed information and the mileage information correspond to examples of vehicle information. By such an operation, the vehicle information is transmitted to the communication line 140 at predetermined short intervals. The vehicle information transmitted through the communication line includes the total mileage and the vehicle speed at the time when the vehicle information is transmitted from the ECU 180 or immediately before the time when the vehicle information is transmitted. Moreover, the vehicle information transmitted through the communication line 140 may be vehicle speed information or mileage information. The vehicle speed information may be vehicle speed data of the vehicle 100 or data of the wheel rotation state. The mileage information may be data on the total mileage of the vehicle 100, or may be data on an integrated mileage or a section mileage measured by an ECU or the like, or data on the wheel rotation state.

[0031] The in-vehicle navigation system 104 includes a navigation function for displaying the position of the vehicle 100 on which the system is mounted on a map on the display device 112, a television function for displaying television images on the display device 112, a DVD function for displaying images played from a DVD on the display device 112, a receiving function for receiving analog voltage signals such as a vehicle speed pulse signal from the outside, a receiving function for receiving digital information from the outside, etc. In order to realize these functions, the in-vehicle navigation system 104 mainly includes the display device 112, the control device 114, the communication unit 120, and the signal input unit 130.

[0032] The display device 112 is a display device capable of displaying television images, map images, DVD images, and other images. The display device 112 may be a known liquid crystal display device or other display device.

[0033] The control device 114 is a device capable of performing various controls, various calculations, various information processing, etc. The control device 114 is a device capable of controlling the display of the display device 112, and is configured as a device capable of causing the display device 112 to display an image based on a predetermined image signal, for example. The control device 114 may be realized by one device, or may be realized by two or more devices.

[0034] In the example of FIG. 1, the control device 114 includes a TV tuner unit 114A, a DVD player 114B, a navigation unit 114C, and the like. The TV tuner unit 114A, the DVD player 114B, and the navigation unit 114C may be configured as separate devices, or a plurality of them may be realized by a common device. The functions included in the control device 114 in the example of FIG. 1 are merely examples, and the control device 114 may have other functions. For example, the in-vehicle navigation system 104 may be provided with a video input terminal that allows input of a video signal from the outside, and the control device 114 may operate to cause the display device 112 to display a video based on the video signal input to the video input terminal. Although not shown, the control device 114 may also be provided with an information processing unit having a calculation device such as a CPU, a storage unit having a storage device such as a semiconductor storage device, and the like.

[0035] The communication unit 120 is a communication device that is electrically connected to the above-mentioned communication line 140 and can receive information transmitted by the communication line 140 and transmit information to the communication line 140. In a representative example, the communication unit 120 has a function of receiving digital signals transmitted via the communication line 140 and a function of transmitting digital signals to the communication line 140. The digital signals received by the communication unit 120 from the communication line 140 can be processed by the control device 114.

[0036] The signal input unit 130 is a portion to which at least a vehicle speed pulse signal is input from outside the in-vehicle navigation system 104. Specifically, the signal input unit 130 has an analog input terminal to which an analog voltage signal is input, and the vehicle speed pulse signal is input as an analog voltage signal to this analog input terminal from outside the in-vehicle navigation system 104.

[0037] The vehicle speed pulse signal input to the signal input unit 130 is, for example, a signal as shown in FIG. 2. As shown in FIG. 2(A), the vehicle speed pulse signal is a signal including a high-level voltage signal or a low-level voltage signal lower than the high-level voltage. The low-level voltage of the vehicle speed pulse signal is a voltage lower than a predetermined first threshold, for example, a voltage of about 0V. The high-level voltage of the vehicle speed pulse signal is a voltage equal to or higher than a predetermined second threshold, for example, a voltage of about 3.5V. The second threshold may be the same as the first threshold, or may be higher than the first threshold. Note that the voltage values ​​exemplified here are merely examples, and the voltage values ​​may be different values. FIG. 2(B) focuses on one or two periods of the vehicle speed pulse signal, and T p is the period, and X is the period of the high-level voltage. In this specification, a vehicle speed pulse signal in a "changing state" is a periodic signal in which the high-level voltage signal and the low-level voltage signal are alternately repeated, and is a signal in which the pulses continue intermittently. A vehicle speed pulse signal in an "unchanging state" is a signal in which either the high-level voltage signal or the low-level voltage signal continues.

[0038] The in-vehicle system 102 is also provided with a vehicle speed pulse signal generating source 170. The vehicle speed pulse signal generating source 170 is configured as a device separate from the adapter 1, and is realized by a known configuration so as to be able to generate a vehicle speed pulse signal corresponding to the speed of the vehicle 100. The vehicle speed pulse signal generating source 170 generates a vehicle speed pulse signal as shown in FIG. 2, for example, with a period inversely proportional to the speed of the vehicle 100. Specifically, when the vehicle speed of the vehicle 100 is V, T pA vehicle speed pulse signal is generated with a period of K / V, and when the vehicle speed changes, the vehicle speed pulse signal is also changed so that the period corresponds to the vehicle speed. In the above formula, K is a predetermined coefficient, for example, a fixed value.

[0039] In the in-vehicle system 102, a display system 110 is realized by including a display device 112 and a control device 114. The display system 110 is a system having a function of performing display and a function of controlling the display.

[0040] The display system 110 switches between a state in which the video display based on the video signal is enabled and a state in which the video display based on the video signal is disabled. The "video display based on a predetermined video signal" is a predetermined type of video display, and may include, for example, a television video display based on a video signal generated based on a television broadcast wave, a DVD playback video display based on a video signal generated when a DVD is played, and a video display based on a video signal provided from an external information device (such as a smartphone) to the in-vehicle navigation system 104. For example, if a television video display is included as one of the "video displays based on a predetermined video signal," the display system 110 displays a television video on the display device 112 when the video display based on the video signal is "enabled" in a case where the television video display is selected. On the other hand, the display system 110 displays an image other than the television video display on the display device 112 when the video display based on the video signal is "disabled" in a case where the television video display is selected.

[0041] When the display system 110 itself has set the image display based on the video signal to "enabled", that is, when the image display based on the video signal is enabled, and the state in which the vehicle speed pulse signal input to the in-vehicle navigation system 104 has a change continues longer than the first reference time, the display system 110 switches the image display based on the video signal to "enabled". On the other hand, when the display system 110 itself has set the image display based on the video signal to "disabled", that is, when the image display based on the video signal is disabled, and the state in which the vehicle speed pulse signal input to the in-vehicle navigation system 104 has no change continues longer than the second reference time, the display system 110 switches the image display based on the video signal to "enabled". The second reference time is set longer than the first reference time. The "state in which the vehicle speed pulse signal has a change" is a state in which the number of pulses in the vehicle speed pulse signal within the first reference time is equal to or greater than a predetermined third threshold value. The third threshold value is a predetermined fixed value, and may be 1 or a number greater than 1. The third threshold value may be different for each model of the in-vehicle navigation system. The "state where there is no change in the vehicle speed pulse signal" refers to a state where the number of pulses in the vehicle speed pulse signal within the second reference time is less than a predetermined fourth threshold. The fourth threshold is a predetermined fixed value, and may be 1 or a number greater than or equal to 1. The fourth threshold may be different for each model of the in-vehicle navigation system.

[0042] The in-vehicle navigation system 104 can also adopt a connection method in which the vehicle speed pulse signal generated by the vehicle speed pulse signal generating source 170 is input to the signal input unit 130. When connected in this way, the vehicle speed pulse signal generated by the vehicle speed pulse signal generating source 170 is received and processed in the in-vehicle navigation system 104, but this connection method does not allow the "function of disabling the image display based on a predetermined image signal while driving" to be released. Therefore, instead of such a connection method, a connection method is used in which the vehicle speed pulse signal generated by the adapter 1 is input from the signal output unit 24 to the signal input unit 130 as shown in FIG. 1.

[0043] 2. Overview of Adapter 1 The adapter 1 shown in Fig. 1 is an adapter for an in-vehicle navigation system. The adapter 1 functions as an intermediate device between an external device provided outside the adapter 1 and the in-vehicle navigation system 104. The adapter 1 has a function of providing a vehicle speed pulse signal to the in-vehicle navigation system 104. The adapter 1 mainly includes a receiving unit 10 and a pulse control unit 20.

[0044] The receiving unit 10 has a function of receiving vehicle information from an external device provided outside the adapter 1 in the vehicle 100. In the example of FIG. 1, the external device is the ECU 180 and the communication line 140. In this specification, the above-mentioned "vehicle information" used by the adapter 1 to generate a vehicle speed pulse signal may be vehicle speed information or mileage information. The above-mentioned vehicle speed information may be any information that can specify the speed of the vehicle 100, for example, vehicle speed data of the vehicle 100, or data on the wheel rotation state. In addition, the above-mentioned mileage information may be any information that can specify the mileage of the vehicle 100, for example, total mileage data of the vehicle 100, an accumulated mileage or a section mileage measured by an ECU or the like, or data on the wheel rotation state. In addition, in the representative example of the first embodiment, the total mileage data of the vehicle 100 is used as an example of the "vehicle information". Specifically, the receiving unit 10 has a function of receiving total mileage data periodically transmitted from the ECU 180 to the communication line 140 in real time. When data is transmitted from ECU 180 to communication line 140, the timing at which the receiving unit 10 receives the data may be immediately after the data is transmitted from ECU 180 to communication line 140 with almost no delay, or may be after a short time has passed. In a representative example, communication line 140 functions as a CAN-BUS, which is a CAN communication line, and vehicle 100 transmits vehicle information via communication line 140 (CAN communication line). Then, receiving unit 10 receives vehicle information (such as the above-mentioned mileage information and vehicle speed information) from communication line 140 (CAN communication line) via CAN communication.

[0045] The pulse control unit 20 has a function of generating a vehicle speed pulse signal based on the vehicle information and transmitting the generated vehicle speed pulse signal to the in-vehicle navigation system 104. When transmitting to the in-vehicle navigation system 104, the pulse control unit 20 can operate to alternately repeat a first period during which a vehicle speed pulse signal in a "changed state" is transmitted and a second period during which a vehicle speed pulse signal in a "no change state" is transmitted, either always or when a predetermined condition is satisfied.

[0046] 1, the pulse control unit 20 includes a calculation unit 22 and a signal output unit 24. The calculation unit 22 is a unit that performs various calculations and information processing, and is a unit that calculates the period of a vehicle speed pulse signal based on the vehicle information received by the receiving unit 10. The signal output unit 24 is a unit that outputs a signal, and is a unit that outputs a vehicle speed pulse signal set to the period calculated by the calculation unit 22.

[0047] 1, the adapter 1 is configured not to receive a vehicle speed pulse signal from an external device provided outside the adapter 1. Specifically, the vehicle speed pulse signal is not provided from the vehicle speed pulse signal generating source 170 to the adapter 1, and a communication line for transmitting an analog voltage signal from the vehicle speed pulse signal generating source 170 to the adapter 1 is not provided.

[0048] 3.Generating and outputting vehicle speed pulse signals When a predetermined start condition is satisfied in the adapter 1, the calculation unit 22 operates to alternately set the second period and the first period and calculate the period of the vehicle speed pulse signal every short time. The start condition may be that the adapter 1 is powered on, that a predetermined operation is performed in the vehicle 100, or that another condition is satisfied.

[0049] In the following description, the length of the first period is P1, and the length of the second period is P2. When the above-mentioned start condition is satisfied, the calculation unit 22 operates to set the second period to the second length (second time) P2, set the first period to the first length (first time) P1, and alternately repeat the second period and the first period. In the representative example shown in FIG. 3 and FIG. 4, the end point of the second period is the start point of the next first period. Also, the end point of the first period is the start point of the next second period. The length (time) P1 of the first period is a predetermined fixed value, and is shorter than the above-mentioned first reference time Tb1. The length (time) P2 of the second period is a predetermined fixed value, and is longer than the above-mentioned second reference time Tb2. The length P2 of the second period is longer than the length P1 of the first period. The length (time) of the second reference time Tb2 is longer than the length (time) of the first reference time Tb1.

[0050] In this embodiment, N pulses are output from the vehicle speed pulse signal generating source 170 every time the vehicle 100 travels 1 km. In the representative example described below, N=2548. This value remains constant even if the speed of the vehicle 100 changes, and for example, whether the vehicle 100 travels at 1 km / h or 100 km / h, the vehicle speed pulse signal generating source 170 generates N pulses (2548 in the representative example) before the vehicle 100 travels 1 km. Therefore, the travel distance D of the vehicle 100 per pulse is p is 1 / N (km) (0.0003924 km in a typical example). Therefore, the travel distance of the vehicle 100 can be calculated by counting the number of pulses.

[0051] In the following explanation, P t is the total number of pulses output by adapter 1 from the reference point (in a typical example, the time when adapter 1 first acquires vehicle information (in a typical example, total mileage data) after the power of adapter 1 is turned on). Note that P t The initial value of is 0. out is the time during which a pulse can be output, and is the remaining time of the first period. out The maximum value of is P1. pIf the calculation time is the "second period" or the "start time of the first period", P out is the total period of the most recent first period. p If the calculation time is "during the first period after the start of the first period," it is the remaining time of the first period after the calculation time.

[0052] For example, the calculation unit 22 determines that the last time the total travel distance data was acquired was d x In the case where the time d x The total mileage determined by the total mileage data acquired in is D x If so, then time d from the reference point x Distance traveled by vehicle 100 to D now D now =D x -D 0 D 0 is the total mileage of the vehicle 100 identified by the vehicle information (in a representative example, total mileage data) that the receiving unit 10 acquires from the communication line 140 at a reference time point. In a representative example, the reference time point is the time point at which the adapter 1 acquires the vehicle information (in a representative example, total mileage data) from the vehicle 100 for the first time after the adapter 1 is turned on.

[0053] The calculation unit 22 calculates the remaining time P of the first period by the following formula 1. out The pulse period of the vehicle speed pulse signal output to p Calculate.

[0054]

number

[0055] According to the above formula 1, the period T p In calculating D now is a "first estimated mileage" that is the mileage of the vehicle 100 identified by the vehicle information acquired by the adapter 1 via the communication line 140. Specifically, D now is the time when the vehicle information (total mileage data in this example) was last acquired. xThe first estimated mileage from the reference time point is calculated by subtracting the total mileage at the reference time point specified by the vehicle information (total mileage data in a representative example) acquired by the adapter 1 from the total mileage of the vehicle 100 specified by the vehicle information acquired in the first step. p ×P t is a "second estimated travel distance" that is an estimated travel distance of the vehicle 100 estimated by the pulse signal provided by the adapter 1 to the in-vehicle navigation system 104. Specifically, D p ×P t is the second estimated travel distance from the reference time point. That is, in this example, the number of pulses P t and the travel distance per pulse D p The distance traveled from the reference time point specified based on the above formula 1 is the "second estimated distance traveled from the reference time point." The calculation unit 22 calculates the number of pulses ((D now -D p ×P t ) / D p ) is the remaining time P of the first period after the calculation time out The period T of the vehicle speed pulse signal to be transmitted in the first period p Set.

[0056] 4 is an enlarged view of a part of FIG. 3. The pulse control unit 20 controls the period T p In the case of setting, the following is done. In addition, in Fig. 3 and Fig. 4, the time d 0 is the reference time, and time d 1 , d 2 , d 3 , d 4 d n , d n+1 , d n+2 , d n+3Assume that the receiver 10 receives the total distance traveled data from the communication line 140 at the timings d n The total travel distance specified by the total travel distance data acquired by the receiving unit 10 from the communication line 140 at the time point is D n At time d n+1 The total travel distance specified by the total travel distance data acquired by the receiving unit 10 from the communication line 140 at the time point is D n+1 At time d n+2 The total travel distance specified by the total travel distance data acquired by the receiving unit 10 from the communication line 140 at the time point is D n+2 Let us assume that.

[0057] At the start of the first period (time t1) shown in FIG. 4, the calculation unit 22 calculates the period T p When calculating the period T p In the example of FIG. 4, the last time the total mileage data was acquired at time t1 was d n At time d n The total mileage determined by the total mileage data acquired in is D n and P out = P1, and D now =D n -D 0 It is. t is the total number of pulses output by the adapter 1 from the reference time point to time t1, so the calculation unit 22 calculates P t The calculation unit 22 can grasp the value of the period T p After calculating the period T p A vehicle speed pulse signal is transmitted to the in-vehicle navigation system 104.

[0058]

number

[0059] The calculation unit 22 calculates the period T p At the time t2, which is advanced by 1, the period T of the vehicle speed pulse signal to be transmitted immediately after the time t2 isp When calculating the period T p Calculate '. However, P out '=P out -T p and D now '=D n -D 0 and P t '=P t +1. The calculation unit 22 calculates the period T p After calculating ', the period T p ' transmits a vehicle speed pulse signal to the in-vehicle navigation system 104.

[0060]

number

[0061] The calculation unit 22 calculates the period T p At time t3, which is advanced by ', the period T p When calculating the period T p Calculate ". However, P out ''=P out '-T p ' and D now ''=D n+1 -D 0 and P t ''=P t '+1, and time d n+1 The total mileage determined by the total mileage data acquired in is D n+1 The calculation unit 22 calculates the period T p After calculating , the period T p '' transmits a vehicle speed pulse signal to the in-vehicle navigation system 104.

[0062]

number

[0063] In response to the reception of the total travel distance data by the reception unit 10 via the communication line 140, the calculation unit 22 applies the above formula 1 to calculate T p When trying to calculate D now =D p ×P t In other words, D now -D p ×P t If such a condition is met, the calculation unit 22 does not treat the most recently received total mileage data as valid, and sets the value D indicated by the next total mileage data to be acquired. n+1 The total distance traveled is shown by the data obtained this time. n Relationship with D n+1 >D n Until then, p The adapter 1 does not perform the process of calculating the total distance traveled, and does not transmit a vehicle speed pulse signal based on the most recently received total distance data to the in-vehicle navigation system 104. An example of a case where such a condition may be satisfied is when the vehicle 100 is stopped immediately after the adapter 1 is turned on.

[0064] 4.Examples of effects The above-described adapter 1 can alternately repeat the first period and the second period so that the first period during which the vehicle speed pulse signal in the "changing state" is transmitted is shorter than the first reference time Tb1, and the second period during which the vehicle speed pulse signal in the "unchanging state" is transmitted is longer than the second reference time Tb2. That is, when the image display based on the image signal is valid during the vehicle running, the adapter 1 can output the vehicle speed pulse signal in the "changing state" during the first period, and can switch to the vehicle speed pulse signal in the "unchanging state" before the image display is invalidated. The adapter 1 can output the vehicle speed pulse signal in the "unchanging state" during the second period, and since such first period and second period are alternately repeated, the in-vehicle navigation system 104 to which the vehicle speed pulse signal is transmitted from the adapter 1 can maintain the valid state of the image display. Furthermore, when setting the cycle of the pulse signal to be transmitted in the first period, the adapter 1 sets the cycle of the pulse signal to be transmitted in the first period based on the difference between a first estimated mileage, which is the mileage of the vehicle specified by the vehicle information, and a second estimated mileage estimated by the pulse signal provided by the adapter 1 to the in-vehicle navigation system 104. Thus, the adapter 1 can execute control that enables the in-vehicle navigation system to display an image while the vehicle is traveling, while reflecting the difference between the actual mileage of the vehicle 100 and the mileage of the vehicle recognized by the in-vehicle navigation system 104.

[0065] For example, the adapter of Patent Document 1 counts the number of pulses of the vehicle speed pulse signal received in the second period, and provides the vehicle speed pulse to the navigation system so that the number of pulses c×(a+b) / b is transmitted in the first period based on the number of pulses c obtained in the second period, the length a of the first period, and the length b of the second period. This method is effective to a certain extent when the length of one pulse of the vehicle speed pulse signal is sufficiently short compared to the length of the second period, but when the length of one pulse of the vehicle speed pulse signal is approximately the same as the length of the second period or longer than the length of the second period, an error occurs between the actual travel distance of the vehicle and the estimated travel distance estimated by the vehicle speed pulse signal provided by the adapter to the navigation system. For example, when the vehicle is traveling at such a low speed that the length of one pulse of the vehicle speed pulse signal is longer than the length of the second period, the adapter is likely to count the number of pulses of the vehicle speed pulse signal received in the second period as 0. If the number of pulses is counted as 0 in this way, the adapter will consider the vehicle to be in a stopped state even though the vehicle is actually moving at a low speed, and will not output a vehicle speed pulse in the first period. As another example, when the length of the second period is about 1.5 times the length of one pulse of the vehicle speed pulse signal received in the second period, it is possible to round down the pulses received in the second period that are less than one pulse. In this case, the adapter counts the number of pulses c received in the second period as 1, which does not accurately reflect the distance traveled by the vehicle in the second period. In this case, the number of pulses calculated by the formula c×(a+b) / b differs from the number of pulses actually generated by the vehicle in the second period and the first period, which results in an error between the vehicle's travel distance recognized by the navigation system (estimated travel distance estimated by the obtained vehicle speed pulse signal) and the actual travel distance of the vehicle. Even if a method of rounding up pulses that are less than one pulse is adopted, the number of pulses c received in the second period will be counted as 2, which does not accurately reflect the distance traveled by the vehicle in the second period, and the same problem will occur.In this way, an error due to the resolution occurs in each first period, and the error accumulates each time the first period arrives. Therefore, in a navigation system that provides a vehicle speed pulse signal in this manner, the actual travel distance of the vehicle and the estimated travel distance estimated by the vehicle speed pulse signal received by the navigation system will differ greatly. In contrast, the adapter 1 of this embodiment can set the period of the vehicle speed pulse signal in a manner that reflects the difference between the first estimated travel distance from the reference time point and the second estimated travel distance from the reference time point, and if the period of the vehicle speed pulse signal can be set in a direction that makes it difficult to cause a "deviation" caused by this difference, the in-vehicle navigation system 104 will be able to grasp the travel distance of the vehicle 100 more accurately. In particular, the adapter 1 can appropriately set the period by reflecting the above difference each time the second estimated travel distance is calculated, so that the problem of the adapter of Patent Document 1 (the problem of the "deviation" becoming large due to the accumulation of errors caused by the resolution each time the first period arrives) does not occur.

[0066] In addition, the pulse control unit 20 can set the period of the vehicle speed pulse signal to be transmitted in the first period based on a first estimated traveling distance identified by each of the vehicle information received by the receiving unit 10 in each of the second period and the first period.

[0067] However, the adapter of Patent Document 1 must always use a vehicle speed pulse signal received from outside the adapter when generating a vehicle speed pulse signal for the first period, and cannot generate a new vehicle speed pulse signal without using a vehicle speed pulse signal generated outside the adapter. In this respect, the adapter has room for improvement. In contrast, the adapter 1 can receive vehicle information from the communication line 140 (CAN communication line) of the vehicle 100 and generate a new vehicle speed pulse signal based on this vehicle information. Therefore, this adapter is advantageous in situations where problems arise when only "vehicle speed pulse signals generated outside the adapter" are used as vehicle information. For example, since a vehicle speed pulse is generated when the wheels rotate to a certain degree, if the vehicle speed is very slow, it takes a very long time from when a pulse is generated until when the next pulse is generated. For this reason, there is a concern that the vehicle speed cannot be grasped in real time for a long period from when a pulse is generated until when the next pulse is generated. On the other hand, in a method of receiving vehicle information from the communication line 140 (CAN communication line), if an ECU or the like outputs vehicle information to the communication line 140 (CAN communication line) at short intervals and the adapter 1 can monitor this vehicle information, it will be possible to obtain vehicle information at short intervals regardless of the vehicle speed even when the vehicle speed is very slow. Therefore, compared to the adapter of Patent Document 1, the frequency of updates can be increased. Furthermore, the adapter 1 of this embodiment employs a method of using vehicle information received from the communication line 140 (CAN communication line), making it easier to employ more detailed information or more diverse information.

[0068] The adapter 1 can determine a certain point in time (in a representative example, the time when the total mileage data is acquired for the first time after the adapter 1 is turned on) as a reference point in time, and can more accurately obtain a second estimated mileage from the reference point in time to the point in time when the pulse was last output. Then, the period of the vehicle speed pulse signal can be set in a manner that reflects the difference between the first estimated mileage from the reference point in time and the second estimated mileage from the reference point in time.

[0069] The adapter 1 is configured not to receive a vehicle speed pulse signal from an external device (specifically, a vehicle speed pulse signal generating source 170) provided outside the adapter 1. This adapter 1 does not require a configuration for receiving a vehicle speed pulse signal or a function for processing the signal after it is received, and can solve the above-mentioned basic problem while simplifying the device configuration or the functions.

[0070] <Second embodiment> The following description relates to the second embodiment. An adapter 201 for an in-vehicle navigation system of the second embodiment has a configuration as shown in Fig. 5. In an in-vehicle system 202 to which the adapter 201 of the second embodiment is applied, the parts other than the adapter 201 have the same configuration and characteristics as the in-vehicle system 102 described above in "1. Overview of the in-vehicle system 102", except that the adapter 201 is configured to receive a vehicle speed pulse signal from a vehicle speed pulse signal generating source 170. In Fig. 5, in the in-vehicle system 202, parts having the same configuration and function as the parts of the in-vehicle system 102 shown in Fig. 1 are assigned the same reference numerals as those of the in-vehicle system 102 in Fig. 1.

[0071] The adapter 201 of the second embodiment differs from the adapter 1 of the first embodiment only in that a vehicle speed pulse signal is input from a vehicle speed pulse signal generating source 170 and that the vehicle speed pulse signal input to the in-vehicle navigation system 104 can be switched between "a vehicle speed pulse signal generated by the pulse control unit 20" and "a vehicle speed pulse signal input from the outside to the adapter 201". The adapter 201 of the second embodiment is similar to the adapter 1 of the first embodiment in other respects. Specifically, the adapter 201 of the second embodiment has the same configuration and features as those described in "2. Overview of the adapter 1" and "3. Generation and output of a vehicle speed pulse signal" above, and further includes a configuration near the switching unit 203. In FIG. 5, the same reference numerals as those of the adapter 1 of FIG. 1 are used for the parts of the adapter 201 that have the same configuration and function as those of the adapter 1 shown in FIG. 1.

[0072] The adapter 201 in Fig. 5 is provided with a switching unit 203. The switching unit 203 switches between a first switching state in which a vehicle speed pulse signal generated by the pulse control unit 20 can be input to the in-vehicle navigation system 104 and a vehicle speed pulse signal input from the outside to the adapter 201 cannot be input to the in-vehicle navigation system 104, and a second switching state in which a vehicle speed pulse signal generated by the pulse control unit 20 cannot be input to the in-vehicle navigation system 104 and a vehicle speed pulse signal input from the outside to the adapter 201 can be input to the in-vehicle navigation system 104. A control device (e.g., the pulse control unit 20) provided in the adapter 201 controls the switching state of the switching unit 203. For example, the pulse control unit 20 switches the switching unit 203 to the first switching state when a first switching condition is satisfied, and switches the switching unit 203 to the second switching state when a second switching condition is satisfied.

[0073] The above-mentioned first switching condition may be, for example, that a predetermined operating device provided outside adapter 201 in vehicle 100 is operated to enter a first operating state, that a predetermined operating device provided in adapter 201 is operated to enter the first operating state, or another condition. The above-mentioned second switching condition may be, for example, that a predetermined operating device provided outside adapter 201 in vehicle 100 is operated to enter a second operating state, that a predetermined operating device provided in adapter 201 is operated to enter the second operating state, or another condition.

[0074] In an example in which the first switching condition is "a predetermined operating device provided outside the adapter 201 in the vehicle 100 is operated to enter a first operating state," a first signal is input from the vehicle 100 to the adapter 201 when a first operation is performed on the operating device to enter the first operating state. When the first signal is input to the adapter 201 in this way, the pulse control unit 20 switches the switching unit 203 to the first switching state. In this case, the vehicle speed pulse signal generated by the pulse control unit 20 can be input to the in-vehicle navigation system 104 via the switching unit 203, while the vehicle speed pulse signal input to the adapter 201 from the outside is blocked by the switching unit 203 and is not input to the in-vehicle navigation system 104. When a second operation is performed on the operating device in the above-mentioned first operating state to enter a second operating state, a second signal is input from the vehicle 100 to the adapter 201. When the second signal is input to the adapter 201 in this way, the pulse control unit 20 switches the switching unit 203 to the second switching state. In this case, the vehicle speed pulse signal generated by the pulse control unit 20 is blocked by the switching unit 203 and is not input to the in-vehicle navigation system 104, and the vehicle speed pulse signal input to the adapter 201 from the outside is input directly to the in-vehicle navigation system 104 through the switching unit 203. When the vehicle speed pulse signal is directly input from the switching unit 203 to the in-vehicle navigation system 104, the vehicle speed pulse signal input to the switching unit 203 may be input to the in-vehicle navigation system 104 as is without being changed, and the present invention is not limited to this example, and the vehicle speed pulse signal input to the adapter 201 from the outside may be input to the in-vehicle navigation system 104 after inverting the phase or amplifying it.

[0075] <Third embodiment> The following description relates to the third embodiment. An adapter 301 for an in-vehicle navigation system of the third embodiment has a configuration as shown in Fig. 6. In an in-vehicle system 302 disclosed in Fig. 6, the configuration and function of an ECU 180 and a communication line 140 are similar to those of the ECU 180 and the communication line 140 in the in-vehicle system 102 in Fig. 1.

[0076] The in-vehicle navigation system 304 provided in the in-vehicle system 302 in Fig. 6 has a navigation function for displaying the position of the vehicle 100 on which the system is mounted on a map on the display device 112, a television function for displaying television images on the display device 112, a DVD function for displaying images reproduced from a DVD on the display device 112, a receiving function for receiving analog voltage signals such as a vehicle speed pulse signal from the outside, a receiving function for receiving digital information from the outside, and the like. In order to realize these functions, the in-vehicle navigation system 304 mainly has the display device 112, the control device 114, the communication unit 120, and the like. The display device 112 is a display device that can display television images, map images, DVD images, and other images. The display device 112 may be a known liquid crystal display device or the like, or may be another display device.

[0077] The control device 114 is a device capable of performing various controls, various calculations, various information processing, etc. The control device 114 is a device capable of controlling the display of the display device 112, and is configured as a device capable of causing the display device 112 to display an image based on a predetermined image signal, for example. The control device 114 may be realized by one device, or may be realized by two or more devices.

[0078] In the example of FIG. 1, the control device 114 includes a TV tuner unit 114A, a DVD player 114B, a navigation unit 114C, and the like. The TV tuner unit 114A, the DVD player 114B, and the navigation unit 114C may be configured as separate devices, or a plurality of them may be realized by a common device. The functions included in the control device 114 in the example of FIG. 1 are merely examples, and the control device 114 may have other functions. For example, the in-vehicle navigation system 104 may be provided with a video input terminal that allows input of a video signal from the outside, and the control device 114 may operate to cause the display device 112 to display a video based on the video signal input to the video input terminal. Although not shown, the control device 114 may also be provided with an information processing unit having a calculation device such as a CPU, a storage unit having a storage device such as a semiconductor storage device, and the like.

[0079] The communication unit 120 is a part that can transmit and receive CAN signals. In the example of Fig. 6, the communication unit 120 is electrically connected to a communication line 330 configured to transmit a CAN signal, and is configured as a communication device that can receive the CAN signal transmitted by the communication line 330 and transmit the CAN signal to the communication line 330. The CAN signal received by the communication unit 120 can be processed by the control device 114.

[0080] The display system 110 of the in-vehicle navigation system 304 disables the video display based on the video signal when the state of the signal input to the communication unit 120 is a CAN signal indicating that the vehicle 100 is traveling and continues for longer than a first reference time while the video display based on the video signal is enabled. The state of the signal input to the communication unit 120 indicating that the vehicle 100 is traveling is, for example, a state in which information including data that can specify that the vehicle speed is equal to or higher than a predetermined speed (for example, vehicle speed data equal to or higher than a predetermined speed) is intermittently input to the communication unit as a CAN signal. Specifically, the display system 110 disables the video display based on the video signal when, for example, the CAN signal indicating that the vehicle 100 is traveling is input to the in-vehicle navigation system 304 intermittently for longer than a first reference time while the video display based on the video signal is enabled. On the other hand, the display system 110 enables the image display based on the image signal when the state of the signal input to the communication unit 120 indicates that the vehicle 100 is stopped and continues for longer than the second reference time while the image display based on the image signal is disabled. The state of the signal input to the communication unit 120 indicating that the vehicle 100 is stopped may be, for example, a state in which a CAN signal indicating that the vehicle 100 is running is not input. Alternatively, it may be a state in which information including data that can specify that the vehicle speed is less than a predetermined speed (for example, vehicle speed data less than a predetermined speed, etc.) is intermittently input to the communication unit as a CAN signal. Specifically, the display system 110 functions to enable the image display based on the image signal when, for example, a state in which a CAN signal indicating that the vehicle 100 is running is not input to the in-vehicle navigation system 304 while the image display based on the image signal is disabled and continues for longer than the second reference time, or when a CAN signal indicating that the vehicle 100 is stopped is intermittently input for longer than the second reference time. The second reference time is set longer than the first reference time.

[0081] The adapter 301 is an adapter for an in-vehicle navigation system. The adapter 301 functions as an intermediate device between an external device provided outside the adapter 301 and the in-vehicle navigation system 304. The adapter 301 has a function of providing a CAN signal to the in-vehicle navigation system 304. The adapter 301 mainly includes a first communication unit 310 and a signal control unit 320.

[0082] The first communication unit 310 includes a first transmission unit 310A and a first reception unit 310B. The first transmission unit 310A is a unit having a function of transmitting information to the communication line 140. The first reception unit 310B is a unit having a function of receiving information from the communication line 140. The first reception unit 310B corresponds to an example of a reception unit, and has a function of receiving vehicle information such as mileage information and vehicle speed information from an external device provided outside the adapter 301 in the vehicle 100. In the example of FIG. 6, the external device is the ECU 180 and the communication line 140. In this embodiment, the "vehicle information" may be vehicle speed information or mileage information. The vehicle speed information may be any information that can specify the speed of the vehicle 100, and may be, for example, vehicle speed data of the vehicle 100 or data on the wheel rotation state. The mileage information may be any information that can specify the mileage of the vehicle 100, and may be, for example, total mileage data of the vehicle 100, an accumulated mileage or a section mileage measured by an ECU or the like, or data such as wheel rotation state. In a representative example, the first receiving unit 310B has a function of receiving vehicle information (for example, total mileage data) periodically transmitted from the ECU 180 to the communication line 140 in real time. When data is transmitted from the ECU 180 to the communication line 140, the first receiving unit 310B may receive the data immediately after the data is transmitted with almost no delay, or may receive the data after a short time has passed. In a representative example, the communication line 140 functions as a CAN-BUS, which is a CAN communication line, and the vehicle 100 transmits vehicle information through the communication line 140 (CAN communication line). Then, the first receiving unit 310B, which corresponds to an example of a receiving unit, receives vehicle information (total mileage information, vehicle speed information, etc.) from the communication line 140 (CAN communication line) through CAN communication.

[0083] The signal control unit 320 includes a calculation unit 322 and a second communication unit 324, and has a function of generating a CAN signal based on the above-mentioned vehicle information received from the communication line 140 (CAN communication line) and transmitting the CAN signal to the in-vehicle navigation system 304. The calculation unit 322 is a part that performs various calculations and information processing, and is a part that calculates various values ​​based on the vehicle information received by the first receiving unit 310B. The second communication unit 324 includes a second transmitting unit 324A and a second receiving unit 324B. The second transmitting unit 324A is a part that has a function of transmitting information to the in-vehicle navigation system 304 via the communication line 330. The second receiving unit 324B is a part that has a function of receiving information from the in-vehicle navigation system 304 via the communication line 330. The second transmitting unit 324A can output a CAN signal. In the adapter 301, when the first receiving unit 310B receives information other than the predetermined vehicle information as a CAN signal from the communication line 140, the adapter 301 transmits the information as it is from the second transmitting unit 324A via the communication line 330 to the in-vehicle navigation system 304. In the adapter 301, when the first receiving unit 310B receives the predetermined vehicle information as a CAN signal from the communication line 140, the adapter 301 can receive the information, generate new information, and transmit it from the second transmitting unit 324A via the communication line 330 to the in-vehicle navigation system 304, or not transmit the information. The predetermined vehicle information in this case may be the above-mentioned vehicle speed information or mileage information. The vehicle speed information may be vehicle speed data of the vehicle 100 or data on the wheel rotation state. The mileage information may be total mileage data of the vehicle 100, or data such as an accumulated mileage, a section mileage, or a wheel rotation state measured by an ECU or the like. In addition, in the adapter 301, when the second receiving unit 324B receives a CAN signal from the in-vehicle navigation system 304 via the communication line 330, the CAN signal is transmitted directly from the first transmitting unit 310A to the communication line 140.

[0084] The signal control unit 320 operates as follows. When a CAN signal indicating that the vehicle 100 is traveling is output intermittently to the communication line 140, the signal control unit 320 alternately repeats a first period during which the state of the signal provided to the communication unit 120 continues in the state of the CAN signal indicating that the vehicle 100 is traveling, and a second period during which the state of the signal of the communication unit 120 continues in the state indicating that the vehicle 100 is stopped. For example, the signal control unit 320 intermittently transmits a CAN signal indicating that the vehicle 100 is traveling (e.g., a signal including data (vehicle speed data, etc.) that can specify that the vehicle speed is equal to or higher than a predetermined speed) to the communication unit 120 during the first period, and performs a response of not transmitting a CAN signal indicating that the vehicle 100 is traveling to the communication unit 120 during the second period, or a response of intermittently transmitting a CAN signal indicating that the vehicle 100 is stopped (e.g., a signal including data (vehicle speed data, etc.) that can specify that the vehicle speed is lower than a predetermined speed) to the communication unit 120. The signal control unit 320 operates to alternately repeat the first and second periods, making the length of the first period shorter than the first reference time, and making the length of the second period longer than the second reference time. The CAN signal indicating that the vehicle 100 is traveling is, for example, a CAN signal including vehicle speed data in which the vehicle speed is greater than 0.

[0085] After the adapter 301 is turned on, the signal control unit 320 acquires a CAN signal (for example, vehicle speed data and travel distance data transmitted from the ECU 180) transmitted from outside the adapter 301 to the communication line 140 in the vehicle 100. Then, every time a CAN signal (vehicle information) is acquired, the signal control unit 320 calculates the vehicle speed and travel distance based on the acquired CAN signal, and transmits a CAN signal including the calculated data to the in-vehicle navigation system 304.

[0086] Specifically, data to be included in the CAN signal is generated as follows. In the following description and in FIG. 7, P1 is the length of the first period, and P2 is the length of the second period. out is the time when the adapter 301 outputs a CAN signal including vehicle speed data to the in-vehicle navigation system 304, and the maximum value is P1. 0is the total mileage of the vehicle 100 at the time of acquisition, which is the first time that the adapter 301 acquires the mileage from the communication line 140 after the adapter 301 is turned on. 0 The adapter 301 has a total running distance of D 0 In a typical example, the time when the adapter 301 is turned on is set to 0, and T 0 is the total distance D that the adapter 301 has traveled since it was turned on. 0 D 1 ,D 2 ,D 3 D n is the total travel distance of the vehicle 100 acquired by the adapter 301 at each timing. 1 ,T 2 ,T 3 T n D 1 ,D 2 ,D 3 D n The time when the adapter 301 acquires each of the above. For example, T 1 Adapter 301 is D 1 is the time when the 2 Adapter 301 is D 2 This is the time when the D t is the cumulative distance traveled since the adapter 301 was powered on, and its initial value at power-on is 0. t is the accumulated time from when the adapter 301 is turned on to the present, and its initial value is 0.

[0087] D now is the total distance traveled D obtained from the communication line 140 n and the total distance traveled D initially acquired from the communication line 140 when the adapter 301 is turned on. 0 From the difference, the cumulative distance traveled since the adapter 301 was turned on D t minus ((D n -D 0 )-D t ) D nIn the first period, T is the total distance traveled acquired from the communication line 140 during the first period, and in the second period, T is the total distance traveled last acquired from the communication line 140 during the second period. now is the difference between the time when the total distance traveled is acquired from the communication line 140 and the time when the total distance traveled is first acquired from the communication line 140 after the adapter 301 is powered on, minus the cumulative time from when the adapter 301 is powered on to the present ((T n -T 0 )-T t ) T n In the first period, T is the time when the total distance traveled was obtained from the communication line 140 during the first period, and in the second period, T is the time when the total distance traveled was last obtained from the communication line 140 during the second period. v The adapter 301 transmits a CAN signal including the vehicle speed data to the in-vehicle navigation system 304, and then transmits the total mileage D n V is the vehicle speed data to be included in the CAN signal that the adapter 301 transmits to the in-vehicle navigation system 304.

[0088] When calculating the value of the vehicle speed (vehicle speed data) to be included in the CAN signal at time t1, the signal control unit 320 calculates V out = P1, and D t =0, T t = 0, and D now =(D 2 -D 0 )-D t Let T now =(T 2 -T 0 )-T t Then, V=D now / T now The vehicle speed is calculated by the formula below. 0 From time T 2 The signal control unit 320 transmits a CAN signal including the value of the vehicle speed (vehicle speed data) calculated in this manner to the in-vehicle navigation system 304 immediately after time t1. 0is the time when the vehicle information (total mileage data in a representative example) is acquired for the first time after the adapter 301 is turned on.

[0089] When calculating the value of the vehicle speed (vehicle speed data) to be included in the CAN signal at time t2, the signal control unit 320 t '=D t +D now Let T t '=T t +T now And V out '=V out -T v And D now '=(D 3 -D 0 )-D t ' and T now '=(T 3 -T 0 )-T t '. Then, V'=D now ' / T now The signal control unit 320 calculates the vehicle speed according to the following formula: ``The signal control unit 320 transmits a CAN signal including the value of the vehicle speed (vehicle speed data) calculated in this manner to the in-vehicle navigation system 304 immediately after time t2.

[0090] When calculating the value of the vehicle speed (vehicle speed data) to be included in the CAN signal at time t3, the signal control unit 320 t ''=D t '+D now ' and T t ''=T t '+T now ' and V out ''=V out '-Tv' and D now ''=(D 4 -D 0 )-D t '' and T now ''=(T 4 -T 0 )-T t ''. And V''=D now '' / T nowThe signal control unit 320 transmits a CAN signal including the value of the vehicle speed (vehicle speed data) calculated in this manner to the in-vehicle navigation system 304 immediately after time t3.

[0091] When calculating the value of the vehicle speed (vehicle speed data) to be included in the CAN signal at time t4, the signal control unit 320 t '''=D t +D now '' and T t '''=T t ''+T now '' and V out '''=P1, D now '''=(D 6 -D 0 )-D t ''' and T now '''=(T 6 -T 0 )-T t Let '''. Then, V'''=D now ''' / T now The vehicle speed is calculated by the formula ".'' The signal control unit 320 transmits a CAN signal including the value of the vehicle speed (vehicle speed data) calculated in this manner to the in-vehicle navigation system 304 immediately after time t4.

[0092] Thus, in this embodiment, the signal control unit 320 transmits a CAN signal including a value of the vehicle speed (vehicle speed data) based on the estimated mileage estimated by the vehicle information last acquired in the second period or the vehicle information acquired in the first period, during the first period. Specifically, when the total mileage is acquired from the communication line 140 immediately before the time point (the most recent acquisition time point in the first period or the last acquisition time point in the second period) when the calculation is performed in the first period (the above-mentioned t1, t2, t3, t4, etc.) and the total mileage is acquired immediately before, the estimated mileage for that period (from the acquisition time point immediately before to the most recent time point) can be calculated by the difference between the most recently acquired total mileage and the total mileage acquired immediately before, and the time required for traveling the estimated mileage can be estimated by the difference in the time when they were acquired. Then, based on these values, the estimated mileage is divided by the time required for traveling the estimated mileage to obtain the vehicle speed during the estimated mileage, and a CAN signal including the value of this vehicle speed (vehicle speed data) can be transmitted to the first period. In the representative example of this embodiment, the adapter 1 transmits a CAN signal including a vehicle speed (vehicle speed data) value to the in-vehicle navigation system 304, but a method may also be used in which the adapter 1 transmits a CAN signal including a mileage data value (e.g., total mileage data, estimated mileage data, etc.) to the in-vehicle navigation system 304.

[0093] <Fourth embodiment> The following description relates to the fourth embodiment. An adapter 401 for an in-vehicle navigation system of the fourth embodiment has a configuration as shown in Fig. 8. An in-vehicle system 402 disclosed in Fig. 8 has the same configuration and function as the in-vehicle system 302 of Fig. 6 except for the adapter 401. The adapter 401 has the same configuration and function as the adapter 301 except for the portion where the switching unit 440 is provided. The adapter 401 has the functions of the adapter 301 of the third embodiment, and further has a switching function by the switching unit 440 added.

[0094] In the in-vehicle system 402 shown in Fig. 8, the switching unit 440 switches between a first switching state and a second switching state. When the switching unit 440 is in the first switching state, the CAN signal transmitted through the communication line 140 can be input directly to the in-vehicle navigation system 104 (specifically, the communication unit 120) via the switching unit 440, and the signal input from the second communication unit 324 to the in-vehicle navigation system 104 is blocked by the switching unit 440. When the switching unit 440 is in the second switching state, the CAN signal transmitted through the communication line 140 is blocked from being input to the in-vehicle navigation system 104 via the switching unit 440, and information input from the second communication unit 324 to the in-vehicle navigation system 104 (specifically, the communication unit 120) is permitted. When the switching unit 440 is in the second switching state, it can operate in the same way as the adapter 301 of the third embodiment.

[0095] 8, for example, a control device (for example, signal control unit 320) provided in adapter 401 controls the switching state of switching unit 440. In this example, signal control unit 320 switches switching unit 440 to the first switching state when a first switching condition is met, and switches switching unit 440 to the second switching state when a second switching condition is met.

[0096] 8, switching unit 440 is inside adapter 401, but may be provided outside adapter 401. In this case or in the example of Fig. 8, if the first switching state is maintained when adapter 401 is powered off, it is useful because it enables input from communication line 140 to in-vehicle navigation system 304 when adapter 401 is powered off.

[0097] <Fifth embodiment> The following description relates to the fifth embodiment. An adapter 501 for an in-vehicle navigation system of the fifth embodiment has a configuration as shown in FIG. 9. In an in-vehicle system 502 to which the adapter 501 of the fifth embodiment is applied, the parts other than the adapter 501 have the same configuration and characteristics as the in-vehicle system 102 described in the above "1. Overview of the in-vehicle system 102", except that the adapter 501 is configured to receive a vehicle speed pulse signal from the vehicle speed pulse signal generating source 170. In addition, the adapter 501 of the fifth embodiment has the same configuration and characteristics as the adapter 1 described in the above "2. Overview of the adapter 1", except that the adapter 501 is configured to obtain a vehicle speed pulse signal from the vehicle speed pulse signal generating source 170 by the signal input unit 510. In FIG. 9, in the in-vehicle system 502, parts having the same configuration and function as the parts of the in-vehicle system 102 shown in FIG. 1 are assigned the same reference numerals as those of the in-vehicle system 102 of FIG. 1.

[0098] 9 is provided with a signal input unit 510. The signal input unit 510 is a portion to which a vehicle speed pulse signal is input as vehicle information from a vehicle speed pulse signal generating source 170 (external device) provided outside the adapter 501 in the vehicle 100.

[0099] The adapter 1 of the first embodiment generates a vehicle speed pulse signal by the method described above in "3. Generation and output of vehicle speed pulse signal" using the vehicle information received from the communication line 140, while the adapter 501 of the fifth embodiment can generate a vehicle speed pulse signal by the method described above in "3. Generation and output of vehicle speed pulse signal" using the vehicle speed pulse signal (vehicle information) input to the signal input unit 510. In this case, the adapter 1 of the fifth embodiment can generate a vehicle speed pulse signal by the method described above in "3. Generation and output of vehicle speed pulse signal" using the vehicle information (vehicle information) input to the signal input unit 510. n (d 0 , d 1 , d 2 , d 3. . )" to a "method of determining the total traveling distance of the vehicle 100 at each time point when the vehicle speed pulse signal input to the signal input unit 510 is received, by the vehicle speed pulse signal input to the signal input unit 510." For example, by counting the number of pulses of the vehicle speed pulse signal input from a reference time point to a certain time point, the traveling distance of the vehicle from the reference time point to the certain time point can be calculated from this pulse number. Apart from this, the vehicle speed pulse signal can be generated by the method described in "3. Generation and output of vehicle speed pulse signal" above.

[0100] In the example of FIG. 9, the receiving unit 10 is configured to be able to receive information from the communication line 140, but such a receiving unit 10 may not be present.

[0101] <Other embodiments> The present invention is not limited to the embodiments described above and in the drawings. For example, the features of the above or later described embodiments can be combined in any combination within a range that does not contradict. Furthermore, any feature of the above or later described embodiments can be omitted unless it is clearly stated as essential. Furthermore, the above described embodiments may be modified as follows.

[0102] In the adapter 1 of the first to fourth embodiments, the total mileage of the vehicle 100 at the time of acquisition is recognized by acquiring mileage information (specifically, data indicating the total mileage of the vehicle 100 at that time) via the communication line 140, but speed information (specifically, data indicating the speed of the vehicle 100 at that time) may be intermittently acquired as vehicle information via the communication line 140, and the total mileage at the time of speed data acquisition may be recognized by integrating the speed of the vehicle 100. For example, when the adapter 1 receives speed data from the communication line 140 at a certain time, the distance traveled by the vehicle 100 during that time can be calculated based on the time from the time when the speed data was received last time to the time when the speed data is received this time and the speed data received this time. By repeating such calculations, the mileage from the reference time to the time when the speed data is received can be calculated each time the speed data is received. The mileage obtained in this manner is called the first estimated mileage D now It may also be used as.

[0103] In the embodiment described above, the reference time was the time when the adapter 1 first received vehicle information (e.g., total mileage data) from the vehicle after the adapter 1 was turned on, but the reference time may also be the time when the adapter 1 was turned on.

[0104] It should be noted that the embodiments disclosed herein are illustrative and not restrictive in all respects. The scope of the present invention is not limited to the embodiments disclosed herein, and is intended to include all modifications within the scope indicated by the claims or within the scope equivalent to the claims. [Explanation of symbols]

[0105] 1,201,301,401,501 :Adapter 10: Receiving section 20: Pulse control section 22: Arithmetic section 24: Signal output section 100: Vehicle 102, 202, 302, 402, 502: In-vehicle systems 104,304: In-vehicle navigation system 110: Display system 112:Display device 114: Control device 114A: TV tuner section 114B:DVD playback section 114C: Navigation section 120: Communications Department 140: Communication line 170: Vehicle speed pulse signal source 180: Electronic Control Unit (ECU) 203: Switching section 310B: First receiving unit (receiving unit) 320: Signal control section 510: Signal input section

Claims

1. An adapter for providing a vehicle speed pulse signal to an in-vehicle navigation system mounted in a vehicle, comprising: The in-vehicle navigation system includes a display system having a display device and a control device that causes the display device to display an image based on a video signal, the display system disables the image display based on the video signal when a state in which the vehicle speed pulse signal input to the in-vehicle navigation system has a change while the image display based on the video signal is enabled continues for a period longer than a first reference time, and enables the image display based on the video signal when a state in which the vehicle speed pulse signal input to the in-vehicle navigation system has no change while the image display based on the video signal is disabled continues for a period longer than a second reference time, the second reference time being set longer than the first reference time, The adapter comprises: a receiving unit that receives vehicle information including at least one of vehicle speed information and travel distance information from an external device provided outside the adapter in the vehicle; a pulse control unit that generates a vehicle speed pulse signal based on the vehicle information and transmits the vehicle speed pulse signal to the in-vehicle navigation system; having The pulse control unit is a first period during which the vehicle speed pulse signal in a changed state is transmitted and a second period during which the vehicle speed pulse signal in a non-changed state is transmitted are alternately repeated, the length of the first period being made shorter than the first reference time, and the length of the second period being made longer than the second reference time; A period of the vehicle speed pulse signal to be transmitted during the first period is set based on a difference between a first estimated travel distance, which is a travel distance of the vehicle specified by the vehicle information, and a second estimated travel distance, which is a travel distance of the vehicle estimated by a vehicle speed pulse signal provided by the adapter to the in-vehicle navigation system. Adapter for car navigation systems.

2. An adapter for providing a vehicle speed pulse signal to an in-vehicle navigation system mounted in a vehicle, comprising: The in-vehicle navigation system includes a display system having a display device and a control device that causes the display device to display an image based on a video signal, the display system disables the image display based on the video signal when a state in which the vehicle speed pulse signal input to the in-vehicle navigation system has a change while the image display based on the video signal is enabled continues for a period longer than a first reference time, and enables the image display based on the video signal when a state in which the vehicle speed pulse signal input to the in-vehicle navigation system has no change while the image display based on the video signal is disabled continues for a period longer than a second reference time, the second reference time being set longer than the first reference time, The adapter comprises: a signal input unit to which a vehicle speed pulse signal is input as vehicle information from an external device provided outside the adapter in the vehicle; a pulse control unit that generates a vehicle speed pulse signal based on the vehicle information and transmits the vehicle speed pulse signal to the in-vehicle navigation system; having The pulse control unit is a first period during which the vehicle speed pulse signal in a changed state is transmitted and a second period during which the vehicle speed pulse signal in a non-changed state is transmitted are alternately repeated, the length of the first period being made shorter than the first reference time, and the length of the second period being made longer than the second reference time; A period of the vehicle speed pulse signal to be transmitted during the first period is set based on a difference between a first estimated travel distance, which is a travel distance of the vehicle specified by the vehicle information, and a second estimated travel distance, which is a travel distance of the vehicle estimated by a vehicle speed pulse signal provided by the adapter to the in-vehicle navigation system. Adapter for car navigation systems.

3. The pulse control unit sets a cycle of the vehicle speed pulse signal to be transmitted in the first period based on the first estimated travel distance specified by each of the vehicle information when the vehicle information is received in each of the second period and the first period.

3. An adapter for an in-vehicle navigation system according to claim 1 or 2.

4. The external device includes a CAN communication line, The vehicle transmits the vehicle information via the CAN communication line, The receiving unit receives the vehicle information from the CAN communication line.

2. An adapter for an in-vehicle navigation system according to claim 1.

5. the second estimated travel distance is a travel distance from a reference time point that is specified based on the number of pulses of a vehicle speed pulse signal provided to the in-vehicle navigation system from the reference time point and a travel distance per pulse, The pulse control unit sets a period of the vehicle speed pulse signal to be transmitted during the first period based on a difference between the first estimated travel distance from the reference time point and the second estimated travel distance from the reference time point.

3. An adapter for an in-vehicle navigation system according to claim 1 or 2.

6. The vehicle speed pulse signal generated by the vehicle is directly input to the in-vehicle navigation system without being input to the in-vehicle navigation system.

3. An adapter for an in-vehicle navigation system according to claim 1 or 2.

7. An adapter for providing a CAN signal to an in-vehicle navigation system mounted in a vehicle, comprising: The in-vehicle navigation system includes a display system having a display device, a control device that causes the display device to display an image based on a video signal, and a communication unit that can receive the CAN signal; the display system disables the video display based on the video signal when the state of the signal input to the communication unit while the video display based on the video signal is enabled continues for a longer period than a first reference time in the state of the CAN signal indicating that the vehicle is traveling, and enables the video display based on the video signal when the state of the signal input to the communication unit while the video display based on the video signal is disabled continues for a longer period than a second reference time in the state of the signal indicating that the vehicle is stopped, and the second reference time is set to be longer than the first reference time; The adapter comprises: a receiving unit that receives vehicle information including at least one of vehicle speed information and travel distance information from an external device provided outside the adapter in the vehicle; a signal control unit that generates the CAN signal based on the vehicle information and transmits the CAN signal to the communication unit; having the signal control unit alternately repeats a first period during which the state of the signal to be provided to the communication unit is maintained in the state of the CAN signal indicating that the vehicle is traveling and a second period during which the state of the signal of the communication unit is maintained in the state indicating that the vehicle is stopped, and sets a length of the first period to be shorter than the first reference time and sets a length of the second period to be longer than the second reference time; An estimated travel distance estimated based on the vehicle information last acquired in the second period or the vehicle information acquired in the first period is calculated by a calculation, and the CAN signal including vehicle speed data or travel distance data based on the estimated travel distance calculated by the calculation is transmitted to the communication unit during the first period. Adapter for car navigation systems.

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