JP2007218703A - Rotational angle detector of rotating shaft - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress a change in the interval between a detector and a section to be detected caused by thermal influence and the difference of the thermal coefficient of expansion between the detector and its mounted section, and the section to be detected. <P>SOLUTION: A rotational angle detector 100 of a rotating shaft includes: a sensor plate 5; a position sensor 10; and first and second lubricant injection nozzles 9a, 9b. The sensor plate 5 is mounted to a crank shaft 4, and a plurality of gear teeth 5G are provided at the outer-periphery section. The position sensor 10 is a magnetic sensor, and counts the number of the gear teeth 5G formed at the outer-periphery section of the sensor plate 5 without any contact. Lubricant L is injected toward the position sensor 10 and its mounted section from the first lubricant injection nozzle 9a. The lubricant L is injected toward the sensor plate 5 from the second lubricant injection nozzle 9b. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an apparatus for detecting a rotation angle of a rotation shaft.

  In a so-called reciprocating type in which the piston reciprocates in the cylinder and in a spark ignition type internal combustion engine or a diesel internal combustion engine, it is important to know the position of the piston in order to determine the ignition timing and fuel injection timing. is there. The position of the piston can be determined based on the rotation angle (crank angle) of the crankshaft that converts the reciprocating motion of the piston into rotational motion. In Patent Document 1, a crank rotor having a plurality of teeth formed on the outer periphery is attached to a crankshaft so as to be integral and rotatable, and a signal corresponding to the tooth width of each tooth is output by a magnetic sensor attached to a cylinder block. A crank angle detection device for an internal combustion engine that knows the angle is disclosed.

Japanese Patent Laid-Open No. 11-107842

  Incidentally, an internal combustion engine, which is a heat engine, converts heat energy into kinetic energy, and generates heat during operation. The distance between the crank rotor and the magnetic sensor changes during the operation of the heat engine due to the influence of heat generated by the heat engine and the difference in linear expansion coefficient between the crank rotor and the magnetic sensor. As a result, there is a problem that the two come into contact with each other, or the distance between the two becomes too large, and the crank angle detection accuracy is lowered.

  The crank angle detection device for an internal combustion engine disclosed in Patent Document 1 is used for an internal combustion engine. However, the difference in linear expansion coefficient between the crank rotor and a magnetic sensor or a cylinder block that is a mounting portion of the magnetic sensor is different. Is not considered, and there is room for improvement on the above problems.

  Therefore, the present invention has been made in view of the above, and in detecting the rotation angle of the rotating shaft, the influence of heat and the difference in the linear expansion coefficient between the detector and its mounting portion and the detected portion are considered. It is an object of the present invention to provide a rotation angle detection device for a rotation shaft that can suppress a change in the interval between the detector and the detected portion.

  In order to solve the above-described problems and achieve the object, a rotation angle detection device for a rotating shaft according to the present invention includes a detected portion provided on a rotating shaft, and the detected portion without contact with the detected portion. Detecting at least one of a detector that outputs a signal for determining a rotation angle of the rotary shaft and a portion to which the detected portion or the detector or the detector is attached. And a temperature adjusting medium ejecting means for adjusting the distance between the detector and the detected portion to a predetermined value by ejecting the temperature adjusting medium.

  This rotation angle detection device for a rotating shaft injects a temperature adjustment medium onto at least one of a detector, a portion to which the detector is attached, or a detected portion. Thereby, the thermal expansion of the part to which the detector is attached or the detected part is controlled, and the distance between the detector and the detected part is controlled to a predetermined size. As a result, it is possible to suppress changes in the distance between the detector and the detected part due to the influence of heat and the difference in linear expansion coefficient between the detector and the part to which the detector is attached and the detected part.

  The rotation angle detection device for a rotation shaft according to the present invention is the rotation angle detection device for the rotation shaft, wherein the interval between the detector and the detected portion is adjusted by adjusting the ejection time of the temperature adjusting medium. It is characterized by adjusting to a predetermined value.

  A rotation angle detection device for a rotation shaft according to the present invention is the rotation angle detection device for the rotation shaft, wherein the detector is disposed between a detection unit of the detector and a portion to which the detector is attached. A dissimilar material part having a linear expansion coefficient larger than that of the detection unit is provided, and the temperature adjusting medium injecting means injects the temperature adjusting medium to the dissimilar material part.

  In the rotation angle detection device for a rotation shaft according to the present invention, in the rotation angle detection device for the rotation shaft, at least the portion to which the detector is attached is made of the same material as that of the detected portion. It is characterized by that.

  According to the rotation angle detection device of the rotation shaft according to the present invention, the detection of the rotation angle of the rotation shaft is caused by the influence of heat and the difference in linear expansion coefficient between the detector and its mounting portion and the detected portion. The change in the interval between the detector and the detected part can be suppressed.

  Hereinafter, the present invention will be described in detail with reference to the drawings. The present invention is not limited to the best mode for carrying out the invention (hereinafter referred to as an embodiment). In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art or those that are substantially the same. The present invention can be applied when detecting the rotation angle of the rotation shaft, and in particular, the rotation angle of the rotation shaft included in a device that generates heat during operation and changes its temperature, such as a heat engine such as an internal combustion engine or an electric motor. This is suitable for detection. In the following description, a so-called crank angle sensor that detects the rotation angle of the crankshaft of the reciprocating internal combustion engine is taken as an example, but the present invention can be similarly applied to a so-called cam sensor that detects the rotation angle of the camshaft.

(Embodiment 1)
In this embodiment, the thermal expansion is controlled by injecting a temperature adjusting medium such as lubricating oil to at least one of the detector, the detector mounting portion, or the detected portion, and the distance between the detector and the detected portion. It is characterized in that is controlled to a predetermined size. In the following description, a configuration in which the temperature adjustment medium is injected to both the detector and the detected part will be described as an example.

  FIG. 1 is an explanatory diagram illustrating an internal combustion engine including a rotation angle detection device for a rotation shaft according to the first embodiment. FIG. 2 is an enlarged view showing the rotation angle detection device for the rotation shaft according to the first embodiment. In this embodiment, the internal combustion engine 1 that is a heat engine is a so-called reciprocating internal combustion engine that converts a reciprocating motion of a piston 3 disposed in a cylinder 2 into a rotational motion by a crankshaft 4. Note that the heat engine according to this embodiment is not limited to such an internal combustion engine, and may be a so-called rotary engine or an external combustion engine such as a Stirling engine.

  A rotation angle detection device 100 for a rotating shaft according to this embodiment includes a position sensor 10 as a detector, a sensor plate 5 as a detected portion, and first and second lubricating oil injection nozzles as temperature adjustment medium injection means. 9a and 9b. A disc-shaped sensor plate 5 that is a detected portion is attached to the crankshaft 4 that is a rotating shaft, and rotates together with the crankshaft 4. The material of the sensor plate 5 is iron (Fe). Further, the sensor plate 5 has a plurality of teeth 5G formed by a plurality of notches provided at a predetermined interval on the outer peripheral portion, and in a part of the outer peripheral portion, it is longer in the circumferential direction than other regions. A large crank position reference tooth 5GB is formed.

  A position sensor 10 is attached to the cylinder block 6. The position sensor 10 is mounted by fixing a mounting base (detector side mounting portion) 10s to the cylinder block 6 with a bolt 11 as a fastening means. Here, the cylinder block 6 is a portion to which the position sensor 10 as a detector is attached, that is, a detector attachment portion. The position sensor 10 is a magnetic sensor, and counts the number of teeth 5G formed on the outer periphery of the sensor plate 5 in a non-contact manner. Since the position of the crank position reference tooth 5GB is known from the signal detected by the position sensor 10, the rotation angle of the crankshaft 4 (hereinafter referred to as the crank angle) is determined by the number of teeth 5G counted from the position of the crank position reference tooth 5GB. I can know. The signal detected by the position sensor 10 is taken into the engine ECU 20 and used here for controlling the ignition timing, fuel injection timing, etc. of the internal combustion engine 1.

  In this embodiment, the sensor plate 5 is used as the detected portion. For example, a non-contact optical sensor is used as the detector, and the crankshaft 4 that is the rotating shaft is used for detection by the optical sensor. May be provided. In this case, the reflector provided on the crankshaft 4 becomes the detected portion.

  During operation of the internal combustion engine 1, the ambient temperature of the sensor plate 5, the crankshaft 4 to which the sensor plate 5 is attached, or the cylinder block 6 to which the position sensor 10 is attached changes. Then, if a difference occurs in the temperature of the sensor plate 5, the crankshaft 4 that is the mounting part thereof, or the cylinder block 6 that is the mounting part of the position sensor 10, even if these linear expansion coefficients are all the same, As a result of the difference in the amount of thermal expansion, the distance between the sensor plate 5 and the position sensor 10 (the distance between the teeth 5G and the detection unit 10p) t changes, and the detection accuracy of the position sensor 10 may be reduced. In addition, the distance between the sensor plate 5 and the position sensor 10 becomes small, and the sensor plate 5 and the position sensor 10 may come into contact with each other.

  Further, for example, when the sensor plate 5 and the crankshaft 4 are made of iron, and the cylinder block 6 that is the mounting portion of the position sensor 10 is made of aluminum alloy, magnesium alloy, or the like, the sensor plate 5 and the cylinder block 6 Have different linear expansion coefficients. Even in such a case, the amount of thermal expansion of the sensor plate 5 and the cylinder block 6 and the like varies depending on the temperature change during operation of the internal combustion engine 1. As a result, the interval between the sensor plate 5 and the position sensor 10 changes, and the position sensor 10 detects. The accuracy may be reduced. In addition, the distance between the sensor plate 5 and the position sensor 10 becomes small, and the sensor plate 5 and the position sensor 10 may come into contact with each other.

  Therefore, in this embodiment, the temperature difference between the position sensor 10 and its mounting portion and the sensor plate 5 can be reduced by injecting the temperature adjusting medium onto the position sensor 10 and its mounting portion and the sensor plate 5. Thereby, the change of the space | interval of the sensor plate 5 and the position sensor 10 resulting from the said temperature difference can be suppressed. As a result, a decrease in detection accuracy of the position sensor 10 can be suppressed, and contact between the sensor plate 5 and the position sensor 10 can also be suppressed.

  In this embodiment, the lubricating oil of the internal combustion engine 1 is used as the temperature adjustment medium. Then, the lubricating oil, which is a temperature adjusting medium, is sprayed onto the position sensor 10 and its mounting portion and the sensor plate 5. Next, this configuration will be described with reference to FIG. As shown in FIG. 1, this internal combustion engine 1 includes a first lubricating oil injection nozzle 9 a that injects lubricating oil L onto the position sensor 10 and its mounting portion, and a second lubricating oil that injects lubricating oil L onto the sensor plate 5. And an injection nozzle 9b. The first and second lubricating oil injection nozzles 9a and 9b may be shared. In this way, the number of parts can be reduced.

  The first and second lubricating oil injection nozzles 9 a and 9 b are connected to a lubricating oil passage 8 formed in the internal combustion engine 1. Lubricating oil L of the internal combustion engine 1 discharged from the oil pump 7 is sent to the lubricating oil passage 8. From the first lubricating oil injection nozzle 9a, the lubricating oil L is injected toward the position sensor 10 and its mounting portion, and from the second lubricating oil injection nozzle 9a, the lubricating oil L toward the sensor plate 5 is injected. Is injected.

  Since both the temperatures of the lubricating oil L injected from the first and second lubricating oil injection nozzles 9a and 9b are substantially the same, the temperatures around the position sensor 10 and its mounting portion and the sensor plate 5 are also substantially the same. . Thereby, the change of the space | interval t of the sensor plate 5 and the position sensor 10 which originates in a temperature difference can be suppressed. As a result, a decrease in detection accuracy of the position sensor 10 can be suppressed, and the possibility of contact between the sensor plate 5 and the position sensor 10 can be reduced.

  Here, when the position sensor 10 is attached with an attachment component interposed between the position sensor 10 and the cylinder block 6, since a material having a different linear expansion coefficient is interposed, a temperature change during the operation of the internal combustion engine 1. Thus, the interval t is more susceptible to influence. In this case, by injecting the lubricating oil L onto the mounting parts and the sensor plate 5, the change in the distance t between the sensor plate 5 and the position sensor 10 due to the temperature change during the operation of the internal combustion engine 1 can be more reliably suppressed. .

  Also, during the period from the cold start of the internal combustion engine 1 to the end of warm-up, compared to after the end of warm-up, the internal combustion engine 1 is inside and outside (for example, inside and outside the cylinder block 6). Although the temperature difference increases, such a configuration can reduce the temperature difference during a transition from cold to end of warm-up. As a result, even during a transition from the cold time to the end of warm-up, a change in the distance t between the sensor plate 5 and the position sensor 10 can be suppressed, and a decrease in detection accuracy of the position sensor 10 can be suppressed. The possibility of contact between the plate 5 and the position sensor 10 can also be reduced.

  Thus, in the internal combustion engine 1 according to this embodiment, the lubricating oil that is a temperature adjusting medium is injected to the position sensor 10 and its mounting portion and the sensor plate 5. As a result, a change in the distance t between the sensor plate 5 and the position sensor 10 can be suppressed regardless of a temperature change during operation of the internal combustion engine 1, and a decrease in detection accuracy of the position sensor 10 can be suppressed. The possibility of contact with the position sensor 10 can also be reduced.

  Note that the mounting portion of the position sensor 10 and the sensor plate 5 may be made of a material having the same linear expansion coefficient. For example, when the sensor plate 5 is iron, the mounting portion (the cylinder block 6 in this embodiment) of the position sensor 10 is iron (for example, cast iron). That is, the material of the mounting portion of the position sensor 10 is matched with the material of the sensor plate 5. Alternatively, the material of the sensor plate 5 may be matched with the material of the mounting portion of the position sensor 10. In this way, the thermal expansion of the mounting portion of the position sensor 10 and the thermal expansion of the sensor plate 5 can be made substantially equal. As a result, the change in the distance t between the sensor plate 5 and the position sensor 10 can be more effectively suppressed regardless of the temperature change during the operation of the internal combustion engine 1. Here, the case where the linear expansion coefficient is the same includes not only the case where the linear expansion coefficient is completely the same, but also the case where one linear expansion coefficient is in a range of ± 10% of the other linear expansion coefficient.

  As described above, in this embodiment, thermal expansion is controlled by injecting a temperature adjusting medium such as lubricating oil onto at least one of a position sensor as a detector, a sensor mounting portion or a sensor plate as a detected portion. Then, the interval between the detector and the detected part is controlled to a predetermined size. Thus, when detecting the rotation angle of the rotating shaft in a device that generates heat during operation, such as a heat engine or an electric motor, the influence of heat and the line between the detector and its mounting portion and the detected portion are detected. It is possible to suppress a change in the interval between the detector and the detected portion due to the difference in expansion coefficient. As a result, a decrease in detection accuracy of the rotation angle by the detector can be suppressed, and the possibility of contact between the detector and the detected portion can be extremely reduced.

  Furthermore, since the diameter of the sensor plate, which is the detected part, can be reduced by the amount that the detection accuracy of the rotation angle can be suppressed by the detector, the stirring of the lubricating oil can be reduced in the internal combustion engine, and the lubricating oil can be reduced between the cylinders. It is possible to increase the communication hole area for communicating the. As a result, the internal friction of the internal combustion engine can be reduced. Here, what comprises the structure of this embodiment has the effect | action and effect similar to this embodiment. The configuration of this embodiment can also be applied to the following embodiments.

(Embodiment 2)
In the second embodiment, the thermal expansion is controlled by injecting a temperature adjustment medium to either the detector side or the detected part, and the distance between the detector and the signal generation part is controlled to a predetermined size. There is a feature in the point. Here, the detector side includes both the detector mounting portion and the detector itself. In the following description, an example of injecting a temperature adjustment medium to the detector will be described.

  FIG. 3 is an explanatory diagram illustrating an internal combustion engine including a rotation angle detection device for a rotation shaft according to the second embodiment. The rotation angle detection device 100a of the rotating shaft according to this embodiment includes a position sensor 10a that is a detector, a sensor plate 5 that is a detected portion, and a first lubricating oil injection nozzle 9a that is a temperature adjusting medium injection unit. Consists of including.

  The rotation angle detecting device 100a of the rotating shaft provided in the internal combustion engine 1a according to this embodiment injects lubricating oil, which is a temperature adjusting medium, into the position sensor 10a as a detector and its mounting portion. Therefore, unlike the rotation shaft rotation angle detection device 100 (FIG. 1) according to the first embodiment, the rotation shaft rotation angle detection device 100a injects the lubricating oil L onto the position sensor 10a and its mounting portion. Only the first lubricating oil injection nozzle (temperature adjusting medium injection means) 9a is provided. The first lubricating oil injection nozzle 9a is connected to a lubricating oil passage 8 formed in the internal combustion engine 1, and injects the lubricating oil L toward the position sensor 10a and its mounting portion.

  FIG. 4 is an enlarged view showing a rotation angle detection device for a rotation shaft according to the second embodiment. In this embodiment, a dissimilar material portion 12 having a linear expansion coefficient higher than that of the detection portion 10ap is provided between the detection portion 10ap of the position sensor 10a that is a detector and the cylinder block 6 that is an attachment portion of the position sensor 10a. It has been. More specifically, the dissimilar material portion 12 is provided between the mounting base (mounting portion) 10as and the detection portion 10ap, and is configured as a part of the position sensor 10a. In the position sensor 10a, the length of the dissimilar material portion 12 changes mainly due to the temperature change of the dissimilar material portion 12. As a result, the interval t between the position sensor 10a and the sensor plate 5 (that is, the interval between the detection unit 10ap and the teeth 5G) changes.

  In this embodiment, the interval t between the position sensor 10a and the sensor plate 5 is widened during operation of the internal combustion engine 1a. And the dissimilar material part 12 provided in the position sensor 10a is comprised with a material with a larger linear expansion coefficient than the detection part 10ap of the position sensor 10a. When the interval t between the position sensor 10a and the sensor plate 5 increases during the operation of the internal combustion engine 1a, the temperature of the different material portion 12 is increased to thermally expand the different material portion 12. Then, the detection part 10ap of the position sensor 10a approaches the sensor plate 5 (moves in the direction of arrow B in FIG. 4). As a result, the interval t between the detection portion 10ap of the position sensor 10a and the sensor plate 5 is reduced, and the interval t becomes an appropriate size. In order to raise the temperature of the dissimilar material part 12, for example, the lubricating oil L having a temperature higher than that of the dissimilar material part 12 of the position sensor 10a is injected from the first lubricant injection nozzle 9a to the dissimilar material part 12.

  FIG. 5 is an enlarged view showing another rotation angle detection device for a rotation shaft according to the second embodiment. The rotation angle detection device 100b of the rotating shaft is connected to the position sensor 10b between the cylinder block 6 which is a mounting portion of the position sensor 10b and the mounting base (detector side mounting portion) 10bs of the position sensor 10b. A dissimilar material portion 13 formed of a material having a different expansion coefficient is provided. In this example, the dissimilar material part 13 is comprised with the material with a larger linear expansion coefficient than the position sensor 10b.

  For example, when the interval t between the position sensor 10b and the sensor plate 5 is configured to be small during operation of the internal combustion engine 1a, the position sensor mounting structure according to this example is applied. When the interval t between the position sensor 10b and the sensor plate 5 becomes small during the operation of the internal combustion engine 1a, the dissimilar material part 13 is thermally expanded by increasing the temperature of the dissimilar material part 13. Then, the detection unit 10bp of the position sensor 10b moves away from the sensor plate 5 (moves in the direction of arrow A in FIG. 5). As a result, the interval t between the position sensor 10b and the sensor plate 5 is increased, and the interval t becomes an appropriate size. In order to raise the temperature of the dissimilar material part 13, for example, the lubricating oil L having a temperature higher than that of the dissimilar material part 13 is injected from the first lubricant injection nozzle 9 a to the dissimilar material part 13.

  FIG. 6 is an explanatory diagram illustrating an example of a configuration of a temperature adjustment medium supply system included in the internal combustion engine according to the second embodiment. The lubricating oil L discharged from the oil pump 7 is injected from the first lubricating oil injection nozzle 9a through the on-off valve 50 which is a temperature adjusting medium injection control means. The on-off valve 50 is controlled by the thermal expansion control device according to this embodiment. When changing the flow rate of the lubricating oil injected from the first lubricating oil injection nozzle 9a, a flow rate adjusting valve may be used instead of the on / off valve 50, and the opening / closing time of the on / off valve per unit time may be set. You may control. Next, a thermal expansion control device for realizing thermal deformation control according to this embodiment will be described.

  FIG. 7 is an explanatory diagram illustrating a configuration of a thermal expansion control device according to the second embodiment. The thermal expansion control device 30 is configured to be incorporated in the engine ECU 20 (see FIG. 1). In addition, separately from the engine ECU 20, the thermal expansion control device 30 according to this embodiment may be prepared and connected to the engine ECU 20. In realizing the thermal deformation control (hereinafter referred to as thermal deformation control) according to this embodiment, the control function of the internal combustion engine 1a provided in the engine ECU 20 is configured so that the thermal expansion control device 30 can be used. Also good.

  The thermal expansion control device 30 includes a processing unit 31 and a storage unit 32. The processing unit 31 further includes a determination unit 33 and an injection control unit 34. These are the parts that execute the thermal deformation control according to this embodiment. The processing unit 31 is configured by combining, for example, a CPU (Central Processing Unit) and a memory.

  The storage unit 32 stores a computer program, a control map, and the like used for thermal deformation control according to this embodiment. Here, the storage unit 32 can be configured by a volatile memory such as a RAM (Random Access Memory), a nonvolatile memory such as a flash memory, or a combination thereof.

  An input port 35 and an output port 36 are connected to the processing unit 31. The input port 35 includes an accelerator opening sensor 41, an air flow sensor 42, an outside air temperature sensor 43, a cooling water temperature sensor (hereinafter referred to as a water temperature sensor) 44, a lubricating oil temperature sensor (hereinafter referred to as an oil temperature sensor) 45, a position sensor thermometer 46, Other sensors are connected, and the processing unit 31 acquires information from the sensors when executing the thermal deformation control according to this embodiment.

  The output port 36 is connected to an on-off valve 50 that is a control target when the processing unit 31 executes the thermal deformation control according to this embodiment. With such a configuration, the thermal expansion control device 30 controls the on-off valve 50 based on information acquired from the water temperature sensor 44, the oil temperature sensor 45, the position sensor thermometer 46, and the like. Next, an example of the thermal deformation control procedure according to this embodiment will be described. In the following description, please refer to FIGS.

  FIG. 8 is a flowchart illustrating a procedure example of control of thermal expansion according to the second embodiment. 9A and 9B are explanatory diagrams illustrating an example of a control map used for controlling thermal expansion according to the second embodiment. In this embodiment, control of thermal expansion of the internal combustion engine 1a to which the position sensor 10a is attached will be described with the attachment structure of the position sensor 10a shown in FIG. During operation of the internal combustion engine 1a to which the position sensor 10a is attached with the attachment structure shown in FIG. 4, the interval t between the position sensor 10a and the sensor plate 5 is configured to be large.

  First, the determination unit 33 of the thermal expansion control device 30 acquires outputs from sensors such as the water temperature sensor 44, the oil temperature sensor 45, and the position sensor thermometer 46 (step S101). Then, the determination unit 33 calculates an interval (hereinafter referred to as clearance) t between the position sensor 10a and the sensor plate 5 based on the output of the sensors, that is, information on the operating state of the internal combustion engine 1a acquired by the sensors. (Step S102).

  The clearance t is determined by the temperature of the internal combustion engine 1a, the temperature of the position sensor 10a, and the like. Therefore, the determination unit 33 of the thermal expansion control device 30 gives the temperature Tc of the position sensor 10a and the temperature Te of the internal combustion engine 1a to the control map 60 shown in FIG. 9-1 and acquires the corresponding clearance t. Here, the temperature Te of the internal combustion engine 1a can be represented by the cooling water temperature or the oil temperature of the internal combustion engine 1a. The clearance t also changes depending on the operating conditions (load factor, engine speed, etc.) of the internal combustion engine 1a and the outside air temperature. For this reason, it is preferable to correct the clearance t according to the load factor of the internal combustion engine 1a, the engine speed, and the outside air temperature.

  Next, the determination unit 33 compares the calculated clearance t with a predetermined clearance allowable value tc (step S103). When t <tc (step S103: No), the clearance t is within the allowable range, and the detection accuracy of the position sensor 10a can be sufficiently ensured. For this reason, returning to START, monitoring of the clearance t is continued.

  If t ≧ tc (step S103: Yes), there is a high possibility that the detection accuracy of the position sensor 10a cannot be ensured. Therefore, the thermal expansion control device 30 injects the lubricating oil L onto the dissimilar material portion 12 of the position sensor 10a. To adjust the clearance t. In this case, the determination unit 33 compares the temperature Tc of the dissimilar material part 12 of the position sensor 10a acquired from the position sensor thermometer 46 with the temperature Tl of the lubricating oil L (step S104).

  When Tc ≧ Tl (step S104: No), since the length of the dissimilar material portion 12 of the position sensor 10a is smaller than the current state, the clearance t is further larger than the current state. Therefore, in this case, the process waits until Tc <Tl. When Tc <Tl, the injection control unit 34 calculates the total injection time Θ of the lubricating oil L (step S105).

  In this embodiment, the total injection time Θ of the lubricating oil L is obtained based on the control map 61. Here, in this control map 61, the unit injection time θ required to lengthen the dissimilar material part 12 of the position sensor 10a by a unit amount (for example, 1 μm) is the difference between the temperature Tc of the dissimilar material part 12 and the temperature Tl of the lubricating oil L. Described in relation. That is, when the temperature Tc of a certain dissimilar material part 12 and the temperature Tl of the lubricating oil L are given to the control map 61, it is necessary to lengthen the dissimilar material part 12 by a unit amount (for example, 1 μm) in the case of Tc and Tl. The unit injection time θ (seconds) can be obtained. That is, the unit of the unit injection time θ is second / μm.

  Since the amount Δt (= t−tc) of extending the dissimilar material part 12 of the position sensor 10a is known from the difference between the clearance t and the clearance allowable value tc, if the injection time θ obtained from the control map 61 is known, the dissimilar material part 12 The total injection time Θ of the lubricating oil L when the temperature and the temperature of the lubricating oil L are Tc and Tl, respectively, can be obtained by Θ = θ × Δt.

  When the total injection time Θ is calculated (step S105), the injection control unit 34 opens the on-off valve 50 for the calculated total injection time Θ and injects the lubricating oil L to the dissimilar material portion 12 of the position sensor 10a (step S106). As a result, the clearance t can be made smaller than the predetermined clearance allowable value tc, so that a decrease in position detection accuracy of the position sensor 10a can be suppressed. Further, contact between the position sensor 10a and the sensor plate 5 can also be suppressed. As a result, the crank angle can be reliably detected. Further, although the temperature of the lubricating oil L is difficult to control, the clearance t can be adjusted relatively easily by controlling the total injection time of the lubricating oil L.

  In this embodiment, the position sensor 10a is provided with the dissimilar material part 12 made of a material having a larger linear expansion coefficient than the detection part 10ap, but without the dissimilar material part 12, the temperature is higher than the temperature of the position sensor 10a. You may make it inject the lubricating oil L of temperature to the position sensor 10a. Even if it does in this way, since the temperature in which the lubricating oil L was injected becomes higher than another part, the part in which the lubricating oil L was injected thermally expands, and the clearance t can be made small. If the dissimilar material portion 12 having a linear expansion coefficient larger than that of the detection portion 10ap is provided, the thermal expansion of that portion becomes larger than the thermal expansion of other portions, so that the clearance t can be reduced more quickly.

  As described above, in this embodiment, the thermal expansion is controlled by injecting a temperature adjusting medium such as lubricating oil to either the detector side or the detected part, and the interval between the detector and the detected part is set to a predetermined value. Control to size. Thereby, when detecting the rotation angle of the rotating shaft in a device that generates heat during operation, due to the influence of heat and the difference in linear expansion coefficient between the detector and its mounting part and the detected part, A change in the interval between the detector and the detected portion can be suppressed. As a result, a decrease in detection accuracy of the rotation angle by the detector can be suppressed, and the possibility of contact between the detector and the detected portion can be extremely reduced.

  Furthermore, since the diameter of the sensor plate, which is the detected part, can be reduced by the amount that the detection accuracy of the rotation angle can be suppressed by the detector, the stirring of the lubricating oil can be reduced in the internal combustion engine, and the lubricating oil It is possible to increase the communication hole area for communicating the. As a result, the internal friction of the internal combustion engine can be reduced. Here, what comprises the structure of this embodiment has the effect | action and effect similar to this embodiment. The configuration of this embodiment can also be applied to the following embodiments.

(Embodiment 3)
The third embodiment is substantially the same as the above-described embodiment except that at least the detector mounting portion is made of the same material as that of the detected portion. FIG. 10 is an explanatory diagram illustrating a configuration of a rotation angle detection device for a rotation shaft according to the third embodiment. In this embodiment, the case where the rotation angle of the camshaft is detected will be described, but the present invention can be similarly applied to a crankshaft, an output shaft, and other rotation shafts.

  The rotation shaft rotation angle detection device 100c according to this embodiment includes a position sensor 10c as a detector, a sensor plate (detected portion) 75 attached to a camshaft 74 housed in the head cover 71, The second lubricant injection nozzles 9a and 9b are included. The position sensor 10c and the sensor plate 75 have the same configuration as the sensor plate 5 described in the first and second embodiments. The head cover 71 includes a first head cover 71A and a second head cover 72B, and is integrated with S. That is, the head cover 71 is configured by:

  Here, the position sensor 10c is attached to the first head cover 71A. The first head cover 71A, which is the attachment portion of the position sensor 10c, is made of the same material as that of the sensor plate 75 that is the detected portion. That is, at least a part (the first head cover 71A in this embodiment) of the head cover 71 that is the attachment portion of the position sensor 10c is made of the same material as that of the sensor plate 75 that is the detected portion.

  For example, when the sensor plate 75 is iron, the material of the first head cover 71A is also iron. As a result, even when a temperature change around the head occurs during operation of the internal combustion engine, the thermal expansion amount of the first head cover 71A, which is the attachment portion of the position sensor 10c, and the thermal expansion amount of the sensor plate 75 are substantially the same amount. Can be. In this embodiment, the lubricating oil is further injected to the position sensor 10c and the sensor plate 75 from the first and second lubricating oil injection nozzles 9a and 9b. As a result, the distance between the position sensor 10c and the sensor plate 75 can be maintained substantially constant, and the detection accuracy of the rotation angle of the camshaft 74 can be maintained. In addition, the risk of contact between the position sensor 10c and the sensor plate 75 can be greatly reduced.

  Here, the second head cover 71B may also be made of the same material (iron in this embodiment) as the first head cover 71A, but may be made of a different material. For example, the second head cover 71B is made of a so-called light alloy such as an aluminum alloy or a magnesium alloy. As a result, it is not necessary to manufacture the entire head cover 71 from iron, and the weight can be reduced accordingly.

  As described above, in this embodiment, at least the detector mounting portion is made of the same material as that of the detected portion and has a thermal expansion coefficient, and a temperature adjusting medium such as lubricating oil is injected to at least one of the detector side or the detected portion. To do. Thereby, the thermal expansion can be controlled more efficiently, and the distance between the detector and the detected part can be maintained at a predetermined size with higher accuracy. As a result, a decrease in detection accuracy of the rotation angle by the detector can be further effectively suppressed, and the risk of contact between the detector and the detected portion can be further reduced.

  Furthermore, since the diameter of the sensor plate, which is the detected part, can be reduced by the amount that the detection accuracy of the rotation angle can be suppressed by the detector, the stirring of the lubricating oil can be reduced in the internal combustion engine, and the lubricating oil can be reduced between the cylinders. It is possible to increase the communication hole area for communicating the. As a result, the internal friction of the internal combustion engine can be reduced.

  As described above, the rotation angle detection device of the rotation shaft according to the present invention is useful for detecting the rotation angle of the rotation shaft, in particular, the influence of heat, and the detector and its mounting portion and the detected portion. It is suitable for suppressing the change in the distance between the detector and the detected portion due to the difference in the linear expansion coefficient.

It is explanatory drawing which shows an internal combustion engine provided with the rotation angle detection apparatus of the rotating shaft which concerns on Embodiment 1. FIG. FIG. 3 is an enlarged view showing a rotation angle detection device for a rotation shaft according to the first embodiment. It is explanatory drawing which shows an internal combustion engine provided with the rotation angle detection apparatus of the rotating shaft which concerns on Embodiment 2. FIG. 6 is an enlarged view showing a rotation angle detection device for a rotation shaft according to Embodiment 2. FIG. It is an enlarged view which shows the rotation angle detection apparatus of the other rotating shaft which concerns on Embodiment 2. FIG. 6 is an explanatory diagram illustrating an example of a configuration of a temperature adjustment medium supply system included in an internal combustion engine according to a second embodiment. FIG. FIG. 6 is an explanatory diagram illustrating a configuration of a thermal expansion control device according to a second embodiment. 6 is a flowchart illustrating an exemplary procedure for controlling thermal expansion according to a second embodiment. It is explanatory drawing which shows an example of the control map used for control of the thermal expansion which concerns on Embodiment 2. FIG. It is explanatory drawing which shows an example of the control map used for control of the thermal expansion which concerns on Embodiment 2. FIG. It is explanatory drawing which shows the structure of the rotation angle detection apparatus of the rotating shaft which concerns on Embodiment 3. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1a Internal combustion engine 2 Cylinder 3 Piston 4 Crankshaft 5 Sensor plate 6 Cylinder block 9a 1st lubricating oil injection nozzle 9b 2nd lubricating oil injection nozzle 10, 10a, 10b, 10c Position sensor 10ap, 10bp detection part 12 Different material part 13 Dissimilar parts 20 Engine ECU
DESCRIPTION OF SYMBOLS 30 Control apparatus 31 Processing part 32 Memory | storage part 33 Determination part 34 Injection control part 50 On-off valve 71 Head cover 71A 1st head cover 72B 2nd head cover 100, 100a, 100b, 100c The rotation angle detection apparatus of a rotating shaft

Claims (4)

A detected part provided on the rotating shaft;
A detector that outputs a signal for determining a rotation angle of the rotating shaft by detecting a position of the detection detection unit in a non-contact manner with the detected portion;
Injecting a temperature adjustment medium to at least one of the detected part or the detector or a part to which the detector is attached, and adjusting the interval between the detector and the detected part to a predetermined value; Temperature adjusting medium jetting means;
A rotation angle detecting device for a rotating shaft.   2. The rotation angle detection device for a rotating shaft according to claim 1, wherein an interval between the detector and the detected portion is adjusted to a predetermined value by adjusting an ejection time of the temperature adjusting medium. Between the detection part of the detector and the part to which the detector is attached, a dissimilar material part having a larger linear expansion coefficient than the detection part of the detector is provided,
3. The rotation angle detection device for a rotating shaft according to claim 1, wherein the temperature adjustment medium injecting unit injects the temperature adjustment medium to the different material portion.   The rotation angle detection device for a rotating shaft according to claim 1 or 2, wherein at least a portion to which the detector is attached is made of a material having the same thermal expansion coefficient as that of the detected portion.

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