Patent Publication Number: US-2022219627-A1

Title: Harness with sensor

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present patent application claims the priority of Japanese patent application No. 2021-002797 filed on Jan. 12, 2021, and the entire contents of Japanese patent application No. 2021-002797 are hereby incorporated by reference. 
     TECHNICAL FIELD 
     The present invention relates to a harness with sensor. 
     BACKGROUND ART 
     Patent Literature 1 discloses a harness with sensor that has a wheel speed sensor to detect a wheel rotational speed. The wheel speed sensor described in Patent Literature 1 includes two detection units for the purpose of redundancy and is configured to be able to output detection signals of the two detection units to different control devices. The harness with sensor described in Patent Literature 1 also includes a first cable being connected to one of the detection units and having a first connector at one end, and a second cable being connected to the other detection unit and having a second connector at one end. 
     CITATION LIST 
     Patent Literature 
     
         
         Patent Literature 1: JP 2019-207257A 
       
    
     SUMMARY OF THE INVENTION 
     The harness with sensor described in Patent Literature 1 is configured in such a manner that the two connectorized cables are attached to the wheel speed sensor. Therefore, with the harness with sensor described in Patent Literature 1, cable routing is likely to be complicated. 
     The invention was made in view of such circumstances and it is an object of the invention to provide a harness with sensor that allows cable routing to be simplified. 
     So as to achieve the above object, one aspect of the present invention provides a harness with sensor, comprising:
         a sensor comprising a plurality of detection units to detect a physical quantity;   a cable comprising a plurality of electric wires connected to the plurality of sensor units and a sheath collectively covering the plurality of electric wires; and   a connector provided at an end portion of the cable opposite to the sensor,   wherein the connector comprises a plurality of connector-connecting portions to respectively output detection signals of the plurality of sensor units.       

     Effect of the Invention 
     According to the present invention, it is possible to provide a harness with sensor that allows cable routing to be simplified. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a schematic configuration diagram illustrating a vehicle in which harnesses with sensors in an embodiment are installed. 
         FIG. 2  is a plan view showing the harness with sensor in the embodiment. 
         FIG. 3  is a cross-sectional view showing a wheel speed sensor in the embodiment. 
         FIG. 4  is a perspective view showing two detection units and four electric wires in the embodiment. 
         FIG. 5  is a cross-sectional view showing a cable in the embodiment. 
         FIG. 6  is a cross-sectional view showing a connector in the embodiment. 
     
    
    
     BEST MODE FOR CARRYING OUT THE INVENTION 
     Embodiment 
     An embodiment of the invention will be described in reference to  FIGS. 1 to 6 . The embodiment below is described as a preferred example for implementing the invention. Although some part of the embodiment specifically illustrates various technically preferable matters, the technical scope of the invention is not limited to such specific aspects. 
     (General Configuration of Vehicle  10 ) 
       FIG. 1  is a schematic configuration diagram illustrating a vehicle  10  in which harnesses  1  with sensors in the present embodiment are installed. In  FIG. 1 , the left side is the front of the vehicle  10  and the right side is the rear of the vehicle  10 . Four wheel-wells  101  are formed on a body of the vehicle  10 , and four wheels  102  on front, rear, right and left sides are respectively arranged in the wheel-wells  101 . In each wheel-well  101 , the harness  1  with sensor is arranged so as to be entirely housed therein. That is, in the present embodiment, the harness  1  with sensor is arranged at a position at which, e.g., the harness  1  with sensor can be hit by foreign matter such as water or stones thrown up by the wheel  102  when the vehicle is in motion. 
     The harness  1  with sensor includes a sensor  2  having two detection units  20  to detect a predetermined physical quantity, a cable  3  to transmit respective detection signals of the two detection units  20 , and a connector  4  provided at an end portion of the cable  3  opposite to the sensor  2 . In the present embodiment, the sensor  2  includes the two detection units  20  for the purpose of redundancy and each of the two detection units  20  detects a rotational speed of the wheel  102 . Hereinafter, the sensor  2  is referred to as the wheel speed sensor  2 . The wheel speed sensor  2  can constitute, e.g., an anti-lock braking system (ABS). Hereinafter, one of the two detection units  20  of the wheel speed sensor  2  is referred to as a first detection unit  21 , the other is referred to as a second detection unit  22 , and it is simply referred to as the detection unit  20  when the first detection unit  21  and the second detection unit  22  are not particularly distinguished. The detection signal of each detection unit  20  is transmitted through the cable  3  and output from the connector  4 . 
     The connector  4  has two connector-connecting portions  42 : a first connector-connecting portion  421  to output the detection signal of the first detection unit  21 , and a second connector-connecting portion  422  to output the detection signal of the second detection unit  22 . The first connector-connecting portion  421  is connected to a first control device  103   a  via a first connection cable  104   a , and the second connector-connecting portion  422  is connected to a second control device  103   b  via a second connection cable  104   b . That is, the first detection unit  21  and the second detection unit  22  are electrically connected to different control devices. 
     The first control device  103   a  is an ECU (Electronic Control Unit) to control mainly operation of the anti-lock braking system, and the second control device  103   b  is an ECU to control mainly operations of devices other than the anti-lock braking system. The second detection unit  22  and the second control device  103   b  serve as a backup for operating the anti-lock braking system properly even when a circuit system including the first detection unit  21  and the second control device  103   b  malfunctions. The first control device  103   a  is positioned on the front side relative to the center position in a longitudinal direction of the vehicle  10  and the second control device  103   b  is positioned on the rear side relative to the center position in the longitudinal direction of the vehicle  10 , but arrangement of these two control devices in the vehicle  10  is not limited thereto. 
     (Harness  1  with Sensor) 
     As shown in  FIG. 1 , one harness  1  with sensor is arranged inside each wheel-well  101  and there are a total of four harnesses  1  with sensors. The following description will be for only one harness  1  with sensor since the four harnesses  1  with sensors have the same configuration in the present embodiment. 
       FIG. 2  is a plan view showing the harness  1  with sensor in the present embodiment.  FIG. 3  is a cross-sectional view showing the wheel speed sensor  2 . The harness  1  with sensor includes the wheel speed sensor  2 , the cable  3  having four electric wires  31  connected to the two detection units  20  and a sheath  32  collectively covering the four electric wires  31 , and the connector  4  provided at an end portion of the cable  3  opposite to the wheel speed sensor  2 . 
     The wheel speed sensor  2  includes the two detection units  20  which are the first detection unit  21  and the second detection unit  22 , and a sensor housing  23  holding the two detection units  20 . As shown in  FIG. 2 , the two detection units  20  are arranged near an annular magnetic encoder  105  that rotates with the wheel  102 . One surface of the magnetic encoder  105  is a magnetized surface  105   a  which is magnetized with N-poles and S-poles alternately in a circumferential direction. 
       FIG. 4  is a perspective view showing the two detection units  20  and the four electric wires  31 . Each detection unit  20  includes a detector main body  201  having a magnetism detection element (not shown) therein, and a pair of lead terminals  202  extending out of the detector main body  201 . The detector main bodies  201  of the two detection units  20  are positioned to overlap with each other in their thickness direction. A main surface of each detection unit  20  is arranged to face the magnetized surface  105   a  of the magnetic encoder  105  (see  FIG. 2 ). The magnetism detection element (not shown) of the detector main body  201  outputs an electric signal according to a cycle of change in magnetic field caused by rotation of the magnetic encoder  105 . As the magnetism detection element, it is possible to use, e.g., a Hall element, a GMR (Giant Magneto-Resistance) element, a TMR (Tunneling Magneto-Resistance) element, etc. The detection signal of the magnetism detection element is output through the pair of lead terminals  202 . 
     As shown in  FIG. 4 , the pair of lead terminals  202  extending out of the detector main body  201  extend on the same side of the detector main body  201  so as to be parallel to each other. Each of the pair of lead terminals  202  is formed in a lengthy elongated plate shape that has a thickness in the thickness direction of the detector main body  201  and is long in a direction of extending from the detector main body  201 . Each of the four lead terminals  202  extending out of the detector main bodies  201  is electrically connected to a different electric wire  31  of the cable  3 . As shown in  FIG. 3 , connecting portions between the four lead terminals  202  and the four electric wires  31  are embedded in the sensor housing  23 . 
     As shown in  FIG. 3 , the two detection units  20 , portions of the four electric wires  31  exposed from the sheath  32  on the wheel speed sensor  2  side, an end portion of the sheath  32  on the wheel speed sensor  2  side and a collar  24  (described later) are embedded in the sensor housing  23 . The sensor housing  23  is formed by insert molding performed in such a manner that the two detection units  20 , the portions of the four electric wires  31  exposed from the sheath  32  on the wheel speed sensor  2  side, the end portion of the sheath  32  on the wheel speed sensor  2  side and the collar  24  are placed in a mold for forming the sensor housing  23  and a resin constituting the sensor housing  23  is injected into the mold. The sensor housing  23  comes into tight contact with the sheath  32  of the cable  3  due to its molding shrinkage, and the sealing property between the sensor housing  23  and the cable  3  is thereby ensured. A length L 1  of the portion of the sheath  32  embedded in the sensor housing  23 , which is a length in the axial direction of the sheath  32 , is not less than a radius R of the cable  3 , and it is not less than a diameter D of the cable  3  (i.e., a diameter of the sheath  32 ) in the present embodiment. This makes it easier to ensure the sealing property between the sensor housing  23  and the cable  3 . 
     The sensor housing  23  has a flange  231  that is located at a center portion in a longitudinal direction of the sensor housing  23  (a horizontal direction in  FIG. 3 ) and protrudes in a direction orthogonal to this longitudinal direction. The collar  24  made of a metal is embedded in the flange  231 . A bolt is inserted into the collar  24  and is screwed into an attachment target to which the wheel speed sensor  2  is attached (e.g., a hub or knuckle arranged inside the wheel-well  101 ), and the wheel speed sensor  2  is thereby bolted to the attachment target. 
       FIG. 5  is a cross-sectional view showing the cable  3 . The cable  3  has the four electric wires  31  and the sheath  32  collectively covering the four electric wires  31  except both end portions. The electric wire  31  is a covered electrical wire formed by covering a center conductor  312  with an insulation coating  311  having electrical insulating properties. The center conductor  312  is a stranded conductor formed by twisting plural strands made of a high electrically conductive material such as copper. The insulation coating  311  is made of, e.g., a flame-retardant cross-linked polyethylene, but it is not limited thereto and may be made of a non-flame-retardant material. The four electric wires  31  are twisted together inside the sheath  32 . The sheath  32  is solid throughout the entire length and directly covers the four electric wires  31 . In other words, the four electric wires  31  are embedded in the sheath  32 . The sheath  32  is formed of, e.g., a thermoplastic urethane. The cable  3  is fixed to, e.g., a wall portion of the vehicle body defining the wheel-well  101  and is arranged along this wall portion. 
     As shown in  FIG. 3 , the center conductors  312  are exposed at end portions of the four electric wires  31  on the wheel speed sensor  2  side by stripping the insulation coatings  311  and the exposed portions of the center conductors  312  are electrically connected to the lead terminals  202  of the wheel speed sensor  2 . Meanwhile, end portions of the four electric wires  31  on the connector  4  side are electrically connected to different terminal fittings  41  of the connector  4 , as shown in  FIG. 6  which will be described later. 
       FIG. 6  is a cross-sectional view showing the connector  4 . The connector  4  includes a connector housing  40  and four terminal fittings  41 . A portion of each of the four terminal fittings  41 , portions of the four electric wires  31  exposed from the sheath  32  on the connector  4  side, and an end portion of the sheath  32  on the connector  4  side are embedded in the connector housing  40 . The connector housing  40  is formed by insert molding performed in such a manner that the four terminal fittings  41 , the portions of the four electric wires  31  exposed from the sheath  32  on the connector  4  side, and the end portion of the sheath  32  on the connector  4  side are placed in a mold for forming the connector housing  40  and a resin constituting the connector housing  40  is injected into the mold. The connector housing  40  comes into tight contact with the cable  3  due to its molding shrinkage, and the sealing property between the connector housing  40  and the cable  3  is thereby ensured. A length L 2  of the portion of the sheath  32  embedded in the connector housing  40 , which is a length in the axial direction of the sheath  32 , is not less than the radius R of the cable  3 , and it is not less than the diameter D of the cable  3  in the present embodiment. In addition, although it is not shown in the drawing, the terminal fittings  41  are crimped onto end portions of the electric wires  31  and are thereby electrically connected (continuous) to the electric wires  31 . The terminal fittings  41  are partially embedded in the connector housing  40  and are thereby held by the connector housing  40 . 
     The connector  4  has two connector-connecting portions  42  (i.e., the first connector-connecting portion  421  and the second connector-connecting portion  422 ) that respectively output the detection signals of the two detection units  20 . In the present embodiment, the two connector-connecting portions  42  have the same shape. Each connector-connecting portion  42  includes a fitting recess  423  formed on the connector housing  40  and a pair of terminal fittings  41  protruding into the fitting recess  423 . The fitting recess  423  is a recessed portion formed so that another connector is fitted thereto. 
     The pair of terminal fittings  41  of the first connector-connecting portion  421  are electrically connected, via a pair of electric wires  31  respectively connected thereto, to the pair of lead terminals  202  of the first detection unit  21 . The pair of terminal fittings  41  of the second connector-connecting portion  422  are electrically connected, via a pair of electric wires  31  respectively connected thereto, to the pair of lead terminals  202  of the second detection unit  22 . This provides a configuration in which the first connector-connecting portion  421  outputs an output signal (detection signal) of the first detection unit  21  and the second connector-connecting portion  422  outputs the detection signal of the second detection unit  22 . It is also configured such that the first connector-connecting portion  421  and the second connector-connecting portion  422  are connected to different connection targets. 
     Another connector to be connected to the first connector-connecting portion  421  is a connector provided at an end portion of the first connection cable  104   a  (see  FIG. 1 ) that connects the first connector-connecting portion  421  and the first control device  103   a , and another connector to be connected to the second connector-connecting portion  422  is the connector  4  provided at an end portion of the second connection cable  104   b  (see  FIG. 1 ) that connects the second connector-connecting portion  422  and the second control device  103   b . However, it is not limited thereto. For example, one of the two connector-connecting portions  42  may be directly connected to the connector  4  provided on the control device  103 . 
     As shown in  FIG. 6 , in the present embodiment, a connection direction CD 1  between the first connector-connecting portion  421  and the other connector to be connected to the first connector-connecting portion  421  (i.e., an opening direction of the fitting recess  423  of the first connector-connecting portion  421 ) and a connection direction CD 2  between the second connector-connecting portion  422  and the other connector to be connected to the second connector-connecting portion  422  (i.e., an opening direction of the fitting recess  423  of the second connector-connecting portion  422 ) are different from each other. It is thereby easy to suppress contact between the two other connectors to be connected to the two connector-connecting portions  42 . From this point of view, an angle formed by the connection direction CD 1  and the connection direction CD 2  is preferably, e.g., not less than 30° and not more than 150°. However, it is not limited thereto, and the connection directions between the two connector-connecting portions  42  and the other connectors may be parallel to each other as long as the two other connectors connected to the two connector-connecting portions  42  do not contact with each other. 
     The connector  4  is fixed, directly or via another member, to the wall portion of the vehicle body defining the wheel-well  101  even though it is not shown in the drawing. However, it is not limited thereto, and the connector  4  may be fixed to a wall portion of the vehicle body outside the wheel-well  101 . 
     Functions and Effects of the Embodiment 
     The harness  1  with sensor in the present embodiment includes the wheel speed sensor  2  having the two detection units  20 , the cable  3  having the four electric wires  31  connected to the two detection units  20  and the sheath  32  collectively covering the four electric wires  31 , and the connector  4  provided at the end portion of the cable  3  opposite to the wheel speed sensor  2 . In addition, the connector  4  includes the two connector-connecting portions  42  that respectively output the detection signals of the two detection units  20 . Therefore, it is possible to avoid arranging plural cables  3  in parallel in a wiring route from the wheel speed sensor  2  to the connector  4  and it is possible to simplify cable routing. That is, when arranging plural cables  3  in parallel in the wiring route from the wheel speed sensor  2  to the connector  4 , it causes problems that, e.g., it becomes necessary to bundle the plural cables  3  or a diameter of the bundled cables  3  is large, but such problems can be solved according to the present embodiment. Particularly in the present embodiment, the wheel speed sensor  2  and the connector  4  are connected by one cable  3 , and it is easier to simplify the cable routing. 
     In addition, one end portion of the sheath  32  is embedded in the sensor housing  23  and the other end portion of the sheath  32  is embedded in the connector housing  40 . Therefore, it is possible to prevent the four electric wires  31  of the cable  3  from being exposed to the outside. It is thereby possible to prevent foreign matter such as water from adhering to the four electric wires  31  or prevents a decrease in durability of the cable  3  caused by exposing the electric wires  31  which have relatively low strength. 
     In addition, the connection directions CD 1  and CD 2  between the two connector-connecting portions  42  and the respectively corresponding other connectors are different from each other. Therefore, the two other connectors respectively connected to the two connector-connecting portions  42  are prevented from coming into contact with each other, and it is thereby possible to improve working efficiency when connecting the connector-connecting portions  42  to the other connectors. 
     In addition, the sheath  32  is solid and directly covers the four electric wires  31 . Therefore, it is possible to reduce the diameter of the cable  3  as compared to when, e.g., a pair of the electric wires  31  connected to the first detection unit  21  are covered with a first cover member, a pair of the electric wires  31  connected to the second detection unit  22  are covered with a second cover member, and these first and second cover members are collectively covered with the sheath  32 . In addition, when the connector housing  40  or the sensor housing  23  is molded with an end portion of the cable  3  inserted in the respective mold, a resin to form the connector housing  40  or the sensor housing  23  can be prevented from entering the inside of the sheath  32  and it is easy to manufacture the harness  1  with sensor. 
     In addition, in the present embodiment, plural connector-connecting portions  42  have the same shape. Therefore, as a temporary solution in the event that, e.g., the first detection unit  21  fails to function, the other connectors connected to the two connector-connecting portions  42  can be swapped and reconnected so that the properly functioning second detection unit  22  can be connected to the first control device  103   a  (i.e., the main control device). 
     As described above, according to the present embodiment, it is possible to provide a harness with sensor that allows cable routing to be simplified. 
     SUMMARY OF THE EMBODIMENT 
     Technical ideas understood from the embodiment will be described below citing the reference numerals, etc., used for the embodiment. However, each reference numeral, etc., described below is not intended to limit the constituent elements in the claims to the members, etc., specifically described in the embodiment. 
     [1] A harness with sensor ( 1 ), comprising: a sensor ( 2 ) comprising a plurality of detection units ( 20 ) to detect a physical quantity; a cable ( 3 ) comprising a plurality of electric wires ( 31 ) connected to the plurality of sensor units ( 20 ) and a sheath ( 32 ) collectively covering the plurality of electric wires ( 31 ); and a connector ( 4 ) provided at an end portion of the cable ( 3 ) opposite to the sensor ( 2 ), wherein the connector ( 4 ) comprises a plurality of connector-connecting portions ( 42 ) to respectively output detection signals of the plurality of sensor units ( 20 ). 
     [2] The harness with sensor ( 1 ) described in [1], wherein the sensor ( 2 ) comprises a sensor housing ( 23 ) holding the plurality of sensor units ( 20 ), wherein the connector ( 4 ) comprises a connector housing ( 40 ) holding a plurality of terminal fittings ( 41 ) respectively connected to the plurality of electric wires ( 31 ), wherein one end of the sheath ( 32 ) is embedded in the sensor housing ( 23 ), and wherein the other end of the sheath ( 32 ) is embedded in the connector housing ( 40 ). 
     [3] The harness with sensor ( 1 ) described in [1] or [2], wherein connection directions (CD 1 , CD 2 ) between the plurality of connector-connecting portions ( 42 ) and respectively corresponding other connectors are different from each other. 
     [4] The harness with sensor ( 1 ) described in any one of [1] to [3], wherein the sheath ( 32 ) is solid and directly covers the plurality of electric wires ( 31 ). 
     [5] The harness with sensor ( 1 ) described in any one of [1] to [4], wherein each of the plurality of detection units ( 20 ) detects a rotational speed of a wheel. 
     Although the embodiment of the invention has been described, the invention according to claims is not to be limited to the embodiment described above. Further, please note that not all combinations of the features described in the embodiment are necessary to solve the problem of the invention. In addition, the invention can be appropriately modified and implemented without departing from the gist thereof. 
     For example, in the embodiment described above, the wheel speed sensor and the connector may be connected by plural cables connected in series. 
     In addition, although the example in which two detection units are provided in the wheel speed sensor has been described in the embodiment described above, it is not limited thereto and, e.g., not less than three detection units may be provided. In this case, the electric wires provided in the cable are twice as many as the number of the detection units, and the connector-connecting portions provided on the connector are the same number as the number of the detection units and respectively output the detection signals of the detection units. 
     In addition, although the plural detection units of the sensor are to detect a wheel rotational speed in the embodiment described above, it is not limited thereto and the plural detection units may have different functions. For example, it may be configured such that one detection unit detects wheel rotational speed and another detection unit detects temperature. 
     In addition, although the two connector-connecting portions have the same shape in the embodiment described above, it is not limited thereto and the plural connector-connecting portions can have different shapes. In this case, it is possible to prevent erroneous fitting.