Air flow rate control apparatus

Abstract

A throttle control apparatus for an engine on a vehicle is provided, in which the number of component parts in the position detection means and the driven means is reduced to improve the accuracy in its position control and at the same time an integrated wiring is achieved and connectors are aggregated. The position detection means for detecting the position of a control valve, the driven means for controlling the position of the control valve, the means for processing control signals, an output from the position control means for controlling the position of the control valve are disposed within a sealed space defined by a body supporting a control valve shaft, and a cover. Based on the fact that the number of component parts of the position detection means may be reduced, the mechanical hysteresis and electrical hysteresis may also be reduced to improve the accuracy in controlling the control valve position, and it is possible to aggregate the connectors.

1. An air flow rate control apparatus for controlling an amount of air to be taken into an engine, comprising:
 a control valve disposed within an air flow passage through which an air flows;  
 a body defining a portion of the air flow passage and rotatably accommodating said control valve;  
 a cover attached to said body;  
 a motor driven means for driving said control valve to a predetermined opening degree;  
 a switching means for selectively disconnecting said driven means from said control valve;  
 a detector for detecting a rotational position of a valve shaft to which said control valve is mounted as an opening degree of said control valve said detector disposed at an end portion of said valve shaft opposite to said motor driven means; and  
 a controller for processing a controlled variable of an opening degree of said control valve in accordance with a detection signal from the detector and outputting to said driven means a command signal corresponding to said controlled variable; and  
 an interface portion allowing an electrical data exchange among said detector, said driven means and said controller, and/or an electrical data exchange between these components and the outside of said apparatus through said interface portion, said interface portion disposed at the same side of said valve shaft as said detector is.  
 
     
     
       2. A motor driven throttle valve system comprising:
 a throttle body in which a throttle valve is mounted;  
 a recess portion provided adjacent said throttle valve for housing therein a motor for driving said throttle valve; and  
 a through hole for communicating said recess portion the outside thereof, through which an electric wire extends from said motor to the outside.  
 
     
     
       3. A motor driven throttle valve system comprising:
 a throttle body with an air intake passage;  
 a throttle valve element disposed in said air intake passage for changing an effective cross sectional area of said passage  
 a throttle shaft rotatably mounted in said throttle body for swinging said throttle valve element;  
 a motor for driving said throttle shaft through gear means provided on one end portion of said throttle shaft;  
 a position sensor provided on the other end portion of said throttle shaft for detecting a rotational displacement of said shaft;  
 a recess portion provided in said throttle body adjacent said throttle valve element for housing therein a motor for driving said throttle valve;  
 a through hole for communicating said recess portion with the outside thereof, through which an electric wire extends from said motor to the outside;  
 a cover member attached to said throttle body for covering said position sensor, through which electric wires from said motor and said position sensor extend out of the system.  
 
     
     
       4. A motor driven throttle valve system comprising:
 a body provided therein with an air intake passage;  
 a shaft rotatably mounted in said body;  
 a throttle valve element fixedly mounted to said shaft for changing an effective cross sectional area of said passage in accordance with a swing of said shaft;  
 a cover attached to said body to define therebetween a space;  
 a sensor disposed within said space for detecting an angular displacement of said shaft;  
 a motor mounted to said body;  
 a mechanism for transmitting a rotational torque from said motor to said shaft; and  
 a connector mounted to said cover, said connector including an output terminal of said sensor and an input terminal of said motor means.  
 
     
     
       5. A motor driven throttle valve system according to  claim 1 , further comprising a lost motion spring mechanism for applying a rotational force against said shaft so as to characterize a transmission characteristic of a torque to be transmitted from said motor to said shaft through said torque transmission mechanism, said spring mechanism being disposed within said space. 
     
     
       6. A motor driven throttle valve system according to  claim 1 , wherein said means and said torque transmission mechanism are provided on opposite end portions of said shaft. 
     
     
       7. A motor driven throttle valve system according to  claim 6 , further comprising a lost motion spring mechanism for applying a rotational force against said shaft so as to characterize a transmission characteristic of a torque to be transmitted from said motor to said shaft through said torque transmission mechanism, said spring mechanism being disposed within said space. 
     
     
       8. An air flow rate control apparatus for controlling an amount of air to be taken into an engine, comprising:
 a control valve disposed within an air flow passage through which said air flows;  
 a body defining a portion of said air flow passage and rotatably accommodating said control valve;  
 a cover attached to said body;  
 a motor driven means for driving said control valve to a predetermined opening degree;  
 a detector for detecting a rotational position of a valve shaft to which said control valve is mounted as an opening degree of said control valve, said detector disposed at an end portion of said valve shaft opposite to said motor driven means; and  
 an interface portion for allowing an electrical data exchange between said detector and said driven means, and the outside of said apparatus through said interface portion, said interface portion disposed at the same side of said valve shaft as said detector is.  
 
     
     
       9. An apparatus according to  claim 8 , wherein an opening for allowing a communication between said space and the outside thereof is provided. 
     
     
       10. An apparatus according to  claim 8 , wherein said interface portion is provided on said cover. 
     
     
       11. An apparatus according to  claim 8 , wherein said driven means further comprises a switching means capable of selectively disconnecting said driven means from said control valve. 
     
     
       12. An apparatus according to  claim 11 , wherein an opening for allowing a communication between said space and the outside thereof is provided. 
     
     
       13. An apparatus according to  claim 11 , wherein said interface portion is provided on said cover. 
     
     
       14. A throttle valve system comprising:
 a throttle body with an air intake passage;  
 a throttle valve element disposed in said air intake passage for changing an effective cross sectional area of said passage;  
 a throttle valve shaft rotatably mounted on a bearing in said throttle body for swinging said throttle valve element;  
 a first metal bushing press-fitted at an outer periphery thereof to a recess portion of said throttle body and coaxially said throttle shaft; and  
 a throttle position sensor, said sensor including: 
 a sensor element;  
 a second metal bushing fitted to said first metal bushing to support said sensor element;  
 a slider rotatably mounted to said second metal bushing;  
 a transmitting member provided between said throttle valve shaft and said slider thereby said slider is rotated by said throttle valve shaft;  
 a conductive element provided on the surface of said throttle position sensor element; and  
 a slider element mounted on said slider for providing electrical contact to said conductive element.  
 
 
     
     
       15. A system according to  claim 14 , wherein a sealing rubber ring is provided between an inner periphery of said first metal bushing and an outer periphery of said throttle valve shaft. 
     
     
       16. A system according to  claim 14 , wherein said slider is axially urged by means of a spring, thereby being in contact with said conductive element at a predetermined contact pressure. 
     
     
       17. A motor driven throttle valve system comprising:
 a throttle body with an air intake passage;  
 a throttle valve element disposed in said air intake passage for changing an effective cross sectional area of said passage;  
 a throttle shaft rotatably mounted in said throttle body for swinging said throttle valve element;  
 a motor for driving said throttle shaft through gear means provided on one end portion of said throttle valve shaft;  
 a throttle position sensor provided on the other end portion of said throttle valve shaft for detecting a rotational displacement of said throttle valve shaft;  
 a recess portion provided in said throttle body adjacent said throttle valve element for housing therein said motor;  
 a microcomputer electrically connected to said throttle position sensor and said motor; and  
 a cover member attached to said throttle body for covering said throttle position sensor and said microcomputer.  
 
     
     
       18. A system according to  claim 17 , said throttle position sensor is covered by a control unit attached to said throttle body, and wherein said microcomputer is attached to said control unit, and wherein said control unit is covered by said cover member. 
     
     
       19. A system according to  claim 17 , wherein said microcomputer is electrically connected to an accelerator position sensor. 
     
     
       20. A system according to  claim 19 , wherein said accelerator position sensor is attached to said cover. 
     
     
       21. An airflow rate control apparatus comprising:
   a throttle valve element,        a body for mounting the throttle valve element,        a motor being mounted within said body for driving the throttle valve element,        a throttle sensor mounted separately from the motor for detecting an opening degree of said throttle valve element, and        a cover means to form a space together with the body, said throttle sensor being located in the space, wherein        the airflow rate control apparatus further comprises a connector into which electrical connections of the motor and the throttle sensor, respectively, are aggregated.     
     
     
       22. A motor driven throttle valve system comprising:
   a throttle body in which a throttle valve is mounted,        a motor for driving said throttle valve via a throttle shaft,        a recess portion formed adjacently to said throttle valve in said throttle body for accommodating said motor so that an axis of the motor is parallel with said throttle shaft,        a position sensor provided on one end of said throttle shaft for detecting a rotational displacement of said throttle shaft, and        a cover member attached to said throttle body at the one end side of said throttle shaft to form a space together with the throttle body for accommodating electric lead lines of said motor and said position sensor, from which the electric lead lines extend out of the system, wherein      said position sensor is disposed in said space, and        said recess portion is connected with said space through a hole by which the electric lead lines of the motor is allowed to extend to the space.       
     
     
       23. An airflow rate control apparatus comprising a throttle valve element driven by a motor, a throttle sensor for detecting an opening degree of said throttle valve element, and a cover means attached to a body for accommodating the throttle sensor in a space formed by the cover means and the body, wherein
   the cover means is provided with a connector, and the motor is electrically connected to the external through said connector.     
     
     
       24. An airflow rate control apparatus comprising a throttle valve element driven by a motor, a throttle sensor for detecting an opening degree of said throttle valve element, and a control unit including a control circuit for the motor, wherein
   the control unit is provided within a cover means provided with a connector as an interface to the external, the cover means forming a space together with a throttle body for accommodating the throttle sensor in the space.     
     
     
       25. An air flow rate control apparatus comprising:
   a throttle valve;        a throttle body supporting the throttle valve;        a motor for driving the throttle valve;        a sensor for detecting an opening degree of the throttle valve; and        a control unit attached to said throttle body, on which a microcomputer is mounted for controlling said motor, wherein      said control unit comprises an electrical terminal to which said sensor is connected, an electrical terminal to which said motor is connected, and a connector for the connection to the external, the electric terminals being electrically connected to the microcomputer, the microcomputer being connected to the external through the connector.       
     
     
       26. An air flow rate control apparatus comprising:
   a throttle valve;        a throttle body in which said throttle valve is mounted;        a cover member fixed to said throttle body through a sealing member disposed therebetween, the cover member forming a space together with said throttle body;        a sensor disposed in said space for detecting an opening degree of said throttle valve; and        a hole connecting said space with the external space of the apparatus.     
     
     
       27. An air flow rate control apparatus comprising:
   a throttle valve;        a throttle body in which a motor is mounted for driving said throttle valve;        a cover member fixed to said throttle body through a sealing member disposed therebetween, the cover member forming a space together with said throttle body;        a sensor disposed in said space for detecting an opening degree of said throttle valve;        a control unit disposed in said space for controlling said motor; and        a hole connecting said space with the external space of the apparatus.     
     
     
       28. An airflow rate control apparatus comprising a throttle valve element driven by a motor; a throttle sensor for detecting an opening degree of the throttle valve element and a control circuit including a control circuit for the motor, wherein the control circuit is provided on or in a cover means provided with a connector as an interface to the outside. 
     
     
       29. An apparatus according to  claim 28 , further comprising a switching means capable of selectively disconnecting said motor from said throttle valve element. 
     
     
       30. An apparatus according to  claim 28 , wherein said connector is provided on said cover means. 
     
     
       31. An apparatus according to  claim 28 , wherein said control circuit is adapted for processing a signal received from said throttle sensor and for outputting a command signal to said motor in response thereto. 
     
     
       32. An apparatus according to  claim 28 , wherein said connector is including an output terminal of said throttle sensor and an input terminal for the connection to an external power supply. 
     
     
       33. An apparatus according to  claim 28 , wherein the cover means forms a space together with a throttle body for accommodating the throttle sensor in the space. 
     
     
       34. An airflow rate control apparatus, comprising a motor, a throttle valve element driven by said motor; a throttle sensor for detecting an opening degree of the throttle valve element, wherein the motor and the sensor are located in a sealed space formed by a body for mounting the throttle valve element and a cover means and electrical connections of the motor and of the throttle sensor respectively, aggregated into a single connector. 
     
     
       35. An apparatus according to  claim 34 , further comprising a switching means capable of selectively disconnecting said motor from said throttle valve element. 
     
     
       36. An apparatus according to  claim 34 , further comprising an opening for communication between said sealed space and ambient surroundings. 
     
     
       37. An apparatus according to  claim 34 , wherein said single connector is provided on said cover means. 
     
     
       38. An apparatus according to  claim 34 , further comprising a controller for processing a signal received via said electrical connections from said throttle sensor and outputting a command signal to said motor in response thereto. 
     
     
       39. An apparatus according to  claim 34 , wherein said connector is operatively mounted to said body and comprises an output terminal of said throttle sensor and an input terminal of said motor. 
     
     
       40. An apparatus according to  claim 34 , further comprising a lost motion mechanism disposed within said sealed space for applying rotational force against a shaft of said throttle valve element in the event of motor malfunction. 
     
     
       41. An apparatus according to  claim 40 , wherein said lost motion mechanism comprises a shaft, a spring holder attached to the shaft and returning springs for applying said rotational force against said shaft. 
     
     
       42. An air flow rate control apparatus, comprising a motor, a throttle valve element driven by said motor, a throttle sensor for detecting an opening degree of said throttle valve element, a cover means operatively attached to a body for accommodating the throttle sensor in a space formed by cover means and said body, and a connector and a terminal formed on an outside surface and an inside surface of said cover means respectively, wherein said motor is electrically connected to said connector through said terminal for connection to ambient. 
     
     
       43. An apparatus according to  claim 42 , further comprising a switching means capable of selectively disconnecting said motor from said throttle valve element. 
     
     
       44. An apparatus according to  claim 42 , further comprising said apparatus further comprises a controller for processing a signal received via said electrical connections from said throttle sensor and outputting a command signal to said motor in response thereto. 
     
     
       45. An apparatus according to  claim 42 , further comprising a lost motion mechanism disposed in said space for applying a rotational force against a shaft said throttle valve element in the event of motor malfunction. 
     
     
       46. An apparatus according to  claim 45 , wherein said lost motion mechanism comprises a shaft, a spring holder attached to the shaft and returning springs for applying said rotational force against said shaft. 
     
     
       47. An airflow rate control apparatus comprising a motor, a throttle valve element driven by said motor, a throttle sensor for detecting an opening degree of said throttle valve element, a control circuit including a control circuit for said motor and a cover means accommodating said control circuit and provided with a connector as an interface to ambient, wherein said cover means forms a space together with a throttle body for accommodating the throttle sensor in the space. 
     
     
       48. An apparatus according to  claim 47 , further comprising switching means capable of selectively disconnecting said motor from said throttle valve element. 
     
     
       49. An apparatus according to  claim 47 , wherein said connector is provided on said cover means. 
     
     
       50. An apparatus according to  claim 47 , wherein said control circuit is configured to process a signal received from said throttle sensor and to output a command signal to said motor in response thereto. 
     
     
       51. An apparatus according to  claim 47 , wherein said connector comprises an output terminal of said throttle sensor and an input terminal for connection to an external power supply. 
     
     
       52. An apparatus according to  claim 47 , further comprising a lost motion mechanism disposed on said space for applying a rotational force against shaft of said throttle valve element in the event of motor malfunction. 
     
     
       53. An apparatus according to  claim 52 , wherein said lost motion mechanism comprises a shaft, a spring holder attached to the shaft and returning springs for applying said rotational force against said shaft.