Throttle device

Abstract

To provide a throttle device which can achieve improvement of moldability, cost reduction, improvement of flexibility in outfitting, downsizing, etc., and detect a temperature and a pressure of intake air with high accuracy.SOLUTION: A throttle device includes: a throttle body 10 having a main passage 12 in which intake air passes, an attachment surface 16 formed on an outer wall, and a communication passage 17 being open on the attachment surface and leading to the main passage; a throttle valve 30 configured to open or close the main passage; and a sensor unit U joined to the attachment surface. The sensor unit U includes: a housing 60 having a joint surface 62 joined to the attachment surface; and a recessed part 63 recessed from the joint surface and leading to the communication passage; a circuit board 70 embedded in the housing; a pressure sensor 80 electrically connected to the circuit board and configured to detect a pressure of the intake air guided to the recessed part; and a temperature sensor 90 electrically connected to the circuit board and configured to detect a temperature of the intake air guided to the recessed part.SELECTED DRAWING: Figure 8

Description

Technical Field

[0001] The present invention relates to a throttle device provided with a sensor for detecting the intake pressure and temperature, which is applied to the intake system of an internal combustion engine mounted on a motorcycle or the like.

Background Art

[0002] In a conventional intake system of a motorcycle or the like, as a sensor unit attached to a throttle body, there is known a unit housing including a joint surface joined to the attachment surface of the throttle body and a hollow cylindrical body protruding from the joint surface, a circuit board embedded in the unit housing, a temperature detection element such as a thermistor connected to the circuit board and disposed inside the cylindrical body, and a resin sealing agent embedded so as to cover the circuit board from the outside (see, for example, Patent Document 1 and Patent Document 2).

[0003] However, in the above sensor unit, since the cylindrical body for housing the intake air temperature sensor is formed to protrude from the joint surface of the unit housing, it is necessary to handle the cylindrical body so as not to collide with other objects, which also causes the entire sensor unit to be enlarged. In addition, since the cylindrical body is arranged so as to protrude into the intake passage of the throttle body, it causes an increase in intake resistance and a decrease in the degree of freedom in mounting on the throttle body. Further, since the cylindrical body is integrally formed with the unit housing, when the unit housing is molded from a resin material, it causes complications such as a mold, a decrease in moldability, and an increase in cost.

[0004] Further, as a throttle device provided with an intake air temperature sensor for detecting the temperature of intake air, there is known a device including a throttle body defining an intake passage and a throttle valve for opening and closing the intake passage, wherein the throttle body includes a bypass passage bypassing the throttle valve and a mounting hole opening to the outside in the middle of the bypass passage, and the intake air temperature sensor is constituted by a cylindrical body inserted into the mounting hole of the throttle body and a temperature detection element disposed inside the cylindrical body (see, for example, Patent Document 3).

[0005] However, in the above-described throttle device, since the intake air temperature sensor is placed in a passage formed in the throttle body, the degree of freedom in mounting the throttle body is reduced. Furthermore, if another sensor (for example, a pressure sensor) is to be placed in addition to the intake air temperature sensor, the degree of freedom in mounting is further reduced, and handling becomes more complicated. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2019-20251 [Patent Document 2] Patent No. 3914128 [Patent Document 3] Japanese Utility Model Publication No. 5-17138 [Overview of the project] [Problems that the invention aims to solve]

[0007] The present invention has been made in view of the above circumstances, and its objective is to provide a throttle device that can improve moldability, reduce costs, increase freedom in outfitting, and miniaturize, while being able to detect intake pressure and temperature with high precision. [Means for solving the problem]

[0008] This invention Regarding the first point of view The throttle device includes a throttle body having a main passage for intake air, a mounting surface formed on its outer wall, and a connecting passage opening into the mounting surface and leading to the main passage; a throttle valve for opening and closing the main passage; and a sensor unit joined to the mounting surface. The sensor unit includes a housing having a joining surface joined to the mounting surface and a recess recessed from the joining surface and leading to the connecting passage; a circuit board embedded in the housing; a pressure sensor electrically connected to the circuit board and leading to the recess for detecting the pressure of the intake air; and a temperature sensor electrically connected to the circuit board and leading to the recess for detecting the temperature of the intake air. The connecting passage includes a first connecting passage and a second connecting passage that connect the recess and the main passage, respectively, the pressure sensor is positioned facing the recess near the first connecting passage, and the temperature sensor is positioned facing the recess near the second connecting passage. It is structured as follows.

[0009] the above Regarding the first point of view In a throttle device, the communication passage may be configured such that the recess communicates with the main passage downstream of the throttle valve.

[0010] the above Regarding the first point of view In a throttle device, the housing may include an annular groove formed on the joint surface so as to surround the recess, and a sealing member that is in close contact with the mounting surface of the throttle body may be arranged in the annular groove.

[0011] the above Regarding the first point of view A throttle device may be configured to include a bypass passage that branches off from the main passage to introduce intake air, bypasses the throttle valve, and leads the intake air back to the main passage, as well as a control valve that adjusts the passage area of ​​the bypass passage.

[0014] the above Regarding the first point of view In a throttle device, the temperature sensor may be a leaded sensor connected to the circuit board via lead wires.

[0015] the above Regarding the first point of view In a throttle device, the housing may include a protruding wall that protrudes within a recess, and a lead-type sensor, which serves as a temperature sensor, may be covered by the protruding wall.

[0016] A throttle device according to a second aspect of the present invention comprises a throttle body having a main passage for intake air, a mounting surface formed on the outer wall, and a connecting passage opening to the mounting surface and leading to the main passage; a throttle valve for opening and closing the main passage; and a sensor unit joined to the mounting surface, wherein the sensor unit includes a housing having a joining surface joined to the mounting surface and a recess recessed from the joining surface and leading to the connecting passage; a circuit board embedded in the housing; a pressure sensor electrically connected to the circuit board for detecting the pressure of intake air led to the recess; and a temperature sensor electrically connected to the circuit board for detecting the temperature of intake air led to the recess, wherein the connecting passage includes a first connecting passage and a second connecting passage that connect the recess and the main passage, respectively. The temperature sensor is a chip-type sensor surface-mounted on a circuit board. The housing includes a protective wall formed deeper than the recess from the joint surface, and an extension passage extending from the recess to the protective wall, with the temperature sensor being covered by the protective wall.

[0018] the above Regarding the second perspective In a throttle device, the extension passage may be configured to include a first extension passage and a second extension passage.

[0019] the above Regarding the second perspective In a throttle device, a configuration may be adopted that includes a passage member fitted into the housing to define a second extension passage.

[0020] the above Regarding the second perspective In the throttle device, a configuration may be adopted in which the first extension passage communicates with the recess and the second extension passage communicates with the second connection passage.

[0021] The above Regarding the second perspective In the throttle device, a configuration may be adopted in which the second extension passage includes a linear passage facing the protective wall and a bent passage interposed between the linear passage and the second connection passage.

[0022] The above Regarding the second perspective In the throttle device, a configuration may be adopted that includes a passage member fitted into the housing to define a second extension passage including a linear passage and a bent passage.

Advantages of the Invention

[0023] According to the throttle device having the above configuration, while achieving improvements in formability, cost reduction, freedom in ship fitting, miniaturization, etc., the intake air pressure and temperature can be detected with high accuracy.

Brief Description of the Drawings

[0024] [Figure 1] It shows a throttle device according to a first embodiment of the present invention, and is an external perspective view seen from an upstream diagonal direction of a main passage through which intake air passes. [Figure 2] It shows a throttle device according to a first embodiment, and is an external perspective view seen from a downstream diagonal direction of a main passage through which intake air passes. [Figure 3] It is an exploded perspective view of a throttle device according to a first embodiment, seen from an upstream diagonal direction of the main passage. [Figure 4] It is an exploded perspective view of a throttle device according to a first embodiment, seen from another upstream diagonal direction of the main passage. [Figure 5] It is a cross-sectional view of a throttle device according to a first embodiment, cut along a plane passing through the valve shaft and the center of the main passage. [Figure 6] In the throttle device according to a first embodiment, it is a partial cross-sectional perspective view showing a bypass passage (upstream passage) for introducing intake air from the upstream main passage. [Figure 7] This is a partial cross-sectional perspective view showing a bypass passage (downstream passage) that leads intake air to the main passage on the downstream side in a throttle device according to the first embodiment. [Figure 8] This is a partial cross-sectional view showing a portion of the region of the communication passages (first communication passage and second communication passage) that connect the recess, which is arranged so as to face the temperature sensor and pressure sensor, to the main passage in a throttle device according to the first embodiment. [Figure 9] This is a perspective cross-sectional view of a sensor unit mounted on a throttle device according to the first embodiment, cut by a plane passing through the center of the pressure sensor. [Figure 10] This is a perspective cross-sectional view of a sensor unit mounted on a throttle device according to the first embodiment, cut by a plane passing through the center of the temperature sensor. [Figure 11] This is a cross-sectional view of a sensor unit mounted on a throttle device according to the first embodiment, cut by a plane passing through the center of the temperature sensor and the center of the pressure sensor. [Figure 12] This is an exploded perspective view showing a sensor unit mounted in a throttle device according to the first embodiment, with the housing and the circuit board to which the temperature sensor and pressure sensor are connected disassembled. [Figure 13] This is a schematic diagram showing the main passage, bypass passage, connecting passages (first connecting passage and second connecting passage), and sensor unit in a throttle device according to the first embodiment. [Figure 14] This is an external perspective view showing a sensor unit mounted on a throttle device according to the second embodiment. [Figure 15] This is a perspective cross-sectional view of a sensor unit mounted on a throttle device according to the second embodiment, cut by a plane passing through the center of an extension passage that guides intake air to a temperature sensor. [Figure 16] This is a cross-sectional view of a sensor unit mounted on a throttle device according to the second embodiment, cut by a plane passing through the center of the temperature sensor and extension passage and the center of the pressure sensor. [Figure 17]This is an exploded perspective view showing a sensor unit mounted on a throttle device according to the second embodiment, with the housing, a passage member fitted into the housing, and a circuit board to which the temperature sensor and pressure sensor are connected. [Figure 18] This is a partial cross-sectional view showing a portion of the region of the communication passages (first communication passage and second communication passage) that connect the recesses, which are arranged so as to face the temperature sensor and pressure sensor, to the main passage in a throttle device according to the second embodiment. [Figure 19] This is a schematic diagram showing the main passage, bypass passage, connecting passages (first connecting passage and second connecting passage), and sensor unit in a throttle device according to the second embodiment. [Figure 20] This is a cross-sectional view of a sensor unit mounted on a throttle device according to the third embodiment, cut by a plane passing through the center of the temperature sensor and extension passage and the center of the pressure sensor. [Figure 21] This is a partial cross-sectional view showing a portion of the region of the communication passages (first communication passage and second communication passage) that connect the recesses, which are arranged so as to face the temperature sensor and pressure sensor, to the main passage in a throttle device according to the third embodiment. [Figure 22] This is a schematic diagram showing the main passage, bypass passage, connecting passages (first connecting passage and second connecting passage), and sensor unit in a throttle device according to the third embodiment. [Modes for carrying out the invention]

[0025] Embodiments of the present invention will be described below with reference to the accompanying drawings. The throttle device of the present invention is installed in the intake system of an engine mounted on a motorcycle, downstream of the air cleaner and in the middle of the intake pipe.

[0026] As shown in Figures 1 to 13, the throttle device according to the first embodiment comprises a throttle body 10, a valve shaft 20 having an axis S, a throttle valve 30, a drive unit 40 for opening and closing the throttle valve 30, a control valve 50, and a sensor unit U. Here, the sensor unit U comprises a housing 60, a circuit board 70, a pressure sensor 80, and a temperature sensor 90.

[0027] The throttle body 10 is made of a metal material such as aluminum and includes an upstream connection part 11a, a downstream connection part 11b, a locking part 11c, an adjustment screw 11d, a main passage 12, a valve shaft hole 13 through which the valve shaft 20 passes, a bypass passage 14, a housing part 15 for housing the adjustment valve 50, a mounting surface 16 formed on the outer wall, a connecting passage 17, and two boss parts 18.

[0028] The upstream connection part 11a is connected to the intake duct that forms the engine's intake system. The downstream connection portion 11b is connected to the joint surface of the engine cylinder head, which forms the engine's intake system, via a sealing member Sr1. The locking portion 11c locks one end 42a of the coil spring 42 included in the drive unit 40. The adjustment screw 11d is used to contact a portion of the locking lever 41c of the drum 41 included in the drive unit 40.

[0029] The main passage 12 carries intake air toward the engine's combustion chamber and is formed in a cylindrical shape extending in the direction of a straight line L perpendicular to the axis S. Furthermore, as shown in Figure 5, the main passage 12 is formed in a conical shape in which the passage area expands toward the upstream side from the region where the throttle valve 30 is located, that is, in a conical shape in which the passage area decreases toward the region where the throttle valve 30 is located from the upstream connection portion 11a. As shown in Figure 5, the valve stem hole 13 is formed as a circular hole through which the valve stem 20 can rotatably pass, and an annular recess 13a for fitting a lip-type seal Rs is formed on the outer side in the direction of the axis S.

[0030] As shown in Figures 6, 7, and 13, the bypass passage 14 consists of an upstream passage 14a that branches off from the main passage 12 upstream of the throttle valve 30, a downstream passage 14b that merges with the main passage 12 downstream of the throttle valve 30, and a connecting passage 14c that is interposed between the upstream passage 14a and the downstream passage 14b and whose passage area is adjusted by the control valve 50. In other words, the bypass passage 14 branches off from the main passage 12 at an opening 14a1 located upstream of the throttle valve 30 to introduce intake air, bypasses the throttle valve 30, and leads the intake air back to the main passage 12 at an opening 14b1 located downstream of the throttle valve 30.

[0031] As shown in Figures 4, 6, and 7, the housing section 15 is a region that houses the valve body 51 of the control valve 50 so that it can reciprocate, and its end face is provided with a screw hole 15a into which a screw b3 is screwed in to fasten a retaining member 54 that fixes the electromagnetic actuator 53 of the control valve 50. The housing section 15 also functions as a connecting passage that connects the upstream passage 14a and the downstream passage 14b.

[0032] As shown in Figures 4 and 5, the mounting surface 16 is formed as a plane perpendicular to the axis S so that the sensor unit U can be mounted. Furthermore, the mounting surface 16 has two screw holes 16a for fastening the sensor unit U with screws b1, an annular recess 16b for fitting the fitting portion 61 of the sensor unit U, and an opening for a communication passage 17.

[0033] As shown in Figures 2 and 8, the communication passage 17 is configured downstream of the throttle valve 30 and consists of a first communication passage 17a and a second communication passage 17b, which open to the mounting surface 16 and lead to the main passage 12, in order to connect the main passage 12 with the recess 63 of the housing 60 that constitutes the sensor unit U. In this way, by forming the communication passage 17 as two passages (first communication passage 17a and second communication passage 17b), it is possible to actively generate an intake air flow from the main passage 12 toward the recess 63 through one of the first communication passage 17a and second communication passage 17b, and an intake air flow from the recess 63 toward the main passage 12 through the other of the first communication passage 17a and second communication passage 17b, thereby achieving an intake air scavenging effect. This prevents intake air from stagnating in the recess 63. The boss portion 18 has a circular hole through which a screw (not shown) passes for fastening the throttle body 10 with the sealing member Sr1 in between, relative to the joint surface of the engine's cylinder head.

[0034] As shown in Figure 5, the valve stem 20 is formed from a metal or the like with a circular cross-section and extends in the axial direction S. It has a slit 21 and two screw holes 22 in the central region into which the throttle valve 30 is fitted, a connecting portion 23 at one end for connecting the drive unit 40, a disc-shaped member 24 at the other end, and an annular groove (not shown) inside the disc-shaped member 24 for fitting a retaining ring W adjacent to the washer. The connecting portion 23 has a double-sided width portion to fit the drum 41 of the drive unit 40 so that it rotates integrally. The disc-shaped member 24 is positioned inside the cylindrical fitting portion 61 of the sensor unit U. Therefore, if a rotational position detection sensor, including a Hall element or the like, is embedded in the bottom wall of the fitting portion 61 of the sensor unit U, it can be used as the detected member.

[0035] The valve stem 20 is passed through the valve stem hole 13 of the throttle body 10, and the throttle valve 30 fitted into the slit 21 is fastened by the screw b2, thereby holding the throttle valve 30 open and closed. Furthermore, the outer surface of the valve stem 20 is sealed by a lip-type seal Rs outside the valve stem hole 13 in the axial direction S, and a washer and retaining ring W are attached to it, and its movement in the axial direction S is restricted in cooperation with the drum 41 attached to the connecting part 23.

[0036] The throttle valve 30 is formed in a roughly disc shape from a metal material or the like, and has a circular hole 31 through which a screw b2 passes, as shown in Figures 2 and 5. The throttle valve 30 is positioned so as to open and close the main passage 12, with the valve stem 20 passing through the valve stem hole 13, then through the slit 21, and fixed to the valve stem 20 by a screw b2. Then, the throttle valve 30 opens the main passage 12 to a desired degree in accordance with the rotation of the valve stem 20.

[0037] As shown in Figures 1, 2, 5, and 7, the drive unit 40 rotates the valve stem 20 around its axis S and includes a drum 41 connected to and fixed to the coupling portion 23 of the valve stem 20, and a coil spring 42 positioned between the drum 41 and the throttle body 10 around the valve stem 20. The drum 41 is equipped with locking holes 41a, 41b into which a wire connected to the throttle grip is locked, and a locking lever 41c for locking the coil spring 42. The locking lever 41c is designed to contact an adjustment screw 11d provided on the throttle body 10 due to the rotational biasing force of the coil spring 42. Therefore, by adjusting the amount the adjustment screw 11d is extended, the valve opening of the throttle valve 30 at the stop position can be set to the desired position. As shown in Figures 1, 2, and 7, the coil spring 42 has one end 42a locked to the locking portion 11c of the throttle body 10 and the other end 42b locked to the locking lever 41c of the drum 41, thereby exerting a rotational biasing force in the direction that closes the throttle valve 30.

[0038] As shown in Figures 3, 4, 6, and 7, the control valve 50 includes a valve body 51, a coil spring 52 that biases the valve body 51 in the opening direction, an electromagnetic actuator 53 that drives the valve body 51 to reciprocate freely in a direction parallel to the axis S, and a retaining member 54 that fixes the electromagnetic actuator 53 to the throttle body 10. Furthermore, the control valve 50 adjusts the flow rate of intake air flowing through the bypass passage 14 by increasing or decreasing the passage area of ​​the bypass passage 14 (connecting passage 14c) during the engine's idle operation range.

[0039] The sensor unit U is mounted on the mounting surface 16 of the throttle body 10 and, as shown in Figures 3, 4, 8 to 12, comprises a housing 60, a circuit board 70, a pressure sensor 80, and a temperature sensor 90.

[0040] The housing 60 is molded from a resin material and includes a fitting portion 61, a joining surface 62, a recess 63, a protruding wall 64 projecting into the recess 63, an annular groove 65, an outer housing recess 66, two boss portions 67 through which the screw b1 passes, and a connector 68.

[0041] The fitting portion 61 is formed in a cylindrical shape with an axis S centered on it so as to fit into an annular recess 16b formed on the mounting surface 16 of the throttle body 10. By fitting the fitting portion 61 into the annular recess 16b, the sensor unit U and the throttle body 10 are positioned. The joint surface 62 is closely joined to the mounting surface 16 of the throttle body 10 and is formed as a plane perpendicular to the axis S.

[0042] As shown in Figures 3, 8, 11, and 12, the recess 63 is recessed in the axial direction S from the joint surface 62 and is formed to have a roughly triangular contour. Intake air from the main passage 12 is guided into the recess 63 through the first communication passage 17a or the second communication passage 17b. An opening 63a is formed in the bottom wall of the recess 63, facing the end face (protective cover 83) of the pressure sensor 80 flush with it.

[0043] As shown in Figures 8, 9, and 11, the protruding wall 64 is formed by a thin wall that protrudes in a hemispherical shape from the bottom wall of the recess 63 so as not to protrude outward from the joint surface 62. Furthermore, the temperature-sensing element 91 of the temperature sensor 90 is positioned adjacent to the inside of the protruding wall 64. The annular groove 65 is formed on the joint surface 62 so as to surround the recess 63 in order to fit the sealing member Sr2.

[0044] As shown in Figures 9 to 11, the outer receiving recess 66 is formed to be recessed from the outer end face opposite to the bonding surface 62, and the circuit board 70 is placed inside it, and a resin sealant R is filled from the outside to embed the circuit board 70. The boss portion 67 is provided with a circular hole through which a screw b1 for fastening the sensor unit U to the throttle body 10 passes. The connector 68 surrounds the terminals electrically connected to the circuit board 70 and is formed to which an external connector is connected.

[0045] The circuit board 70 has various electronic components and printed wiring mounted on its surface, and multiple terminals are electrically connected. As shown in Figures 9 to 11, the lead wires 82 of the pressure sensor 80 and the lead wires 92 of the temperature sensor 90 are electrically connected.

[0046] As shown in Figures 8, 9, 11, and 12, the pressure sensor 80 includes a pressure-receiving section 81, such as a diaphragm equipped with a semiconductor strain gauge, lead wires 82 extending from the pressure-receiving section 81, and a protective cover 83. In other words, the pressure sensor 80 is electrically connected to the circuit board 70 by lead wires 82, and the protective cover 83 is positioned so as to be flush with the bottom wall of the recess 63 at the opening 63a of the recess 63. In this state, as shown in Figure 8, the pressure sensor 80 is positioned closer to the first communication passage 17a and facing the recess 63.

[0047] The pressure sensor 80 is positioned so as not to protrude outward from the joint surface 62, facing the recess 63, and detects the pressure of the intake air that has been guided from the main passage 12 to the recess 63 via the communication passage 17 (first communication passage 17a, second communication passage 17b) through the small-diameter hole 83a of the protective cover 83.

[0048] As shown in Figures 8, 10, 11, and 12, the temperature sensor 90 is a lead-type sensor and includes a temperature-sensing element 91, such as a thermistor, and lead wires 92 extending from the temperature-sensing element 91. In other words, the temperature sensor 90 is positioned adjacent to the inside of the protruding wall 64 that protrudes within the recess 63, with the temperature sensing element 91, and the lead wires 92 are electrically connected to the circuit board 70. In this state, as shown in Figure 8, the temperature sensor 90 is positioned closer to the second communication passage 17b and facing the recess 63.

[0049] The temperature sensor 90 is located within the recess 63 and covered by a protruding wall 64 so as not to protrude outward from the joint surface 62. It detects the temperature of the intake air guided from the main passage 12 to the recess 63 via the communication passage 17 (first communication passage 17a, second communication passage 17b) through the protruding wall 64.

[0050] In this way, the pressure sensor 80 and the temperature sensor 90 are positioned so as not to protrude from the joint surface 62, which contributes to improving the moldability of the housing 60 and miniaturizing the sensor unit U, as well as preventing interference with external parts, and therefore preventing damage to the pressure sensor 80 and the temperature sensor 90. Furthermore, since the pressure sensor 80 has a pressure-receiving section 81 covered by a protective cover 83 with a small-diameter hole 83a, carbon and other substances introduced by intake air backflow can be prevented from directly adhering to the pressure-receiving section 81. This allows for highly accurate detection of intake air pressure. Similarly, since the temperature sensor 90 has a temperature-sensing element 91 covered by a protruding wall 64 which is a protective wall made of resin material or the like, carbon and other substances introduced by intake air backflow can be prevented from directly adhering to the temperature-sensing element 91. This allows for highly accurate detection of intake air temperature.

[0051] As described above, the sensor unit U houses the pressure sensor 80 and the temperature sensor 90 so that they do not protrude from the joint surface 62. In particular, interference between the temperature sensor 90 and external parts can be prevented, thus preventing damage and allowing for miniaturization. Furthermore, compared to the conventional configuration in which the temperature sensor protrudes from the joint surface and is inserted into the throttle body, the shape of the throttle body 10 can be simplified, and the degree of freedom in mounting to the throttle body 10 is also improved. In addition, the moldability of the housing 60 is improved, and cost reduction can be achieved.

[0052] Next, we will explain the assembly process for the throttle device configured as described above. First, the throttle body 10, valve stem 20, throttle valve 30, drive unit 40, control valve 50, sensor unit U, lip-type seal Rs, sealing member Sr2, washer and retaining ring W, and screws b1, b2, b3 are prepared. The sensor unit U is prepared as a module in which a circuit board 70, to which a pressure sensor 80 and a temperature sensor 90 are connected, is embedded in a housing 60.

[0053] Next, a lip-type seal Rs is fitted into the annular recess 13a of the throttle body 10, and the valve stem 20, to which the disc-shaped member 24, washer, and retaining ring W are attached, is passed through the valve stem hole 13 from the mounting surface 16 side. Then, the throttle valve 30 is inserted into the slit 21 of the valve stem 20 and fixed to the valve stem 20 by a screw b2. Next, the drive unit 40 is connected to the coupling portion 23 of the valve stem 20. Specifically, the coil spring 42 is arranged around the valve stem 20, and the drum 41 is connected to the coupling portion 23 of the valve stem 20 from the outside and secured with a nut.

[0054] Then, one end 42a of the coil spring 42 is locked to the locking portion 11c of the throttle body 10, and the other end 42b of the coil spring 42 is locked to the locking lever 41c of the drum 41. Furthermore, the rotational angle position of the drum 41 is set to a predetermined angle by appropriately adjusting the amount that the adjustment screw 11d, which contacts the locking lever 41c, is extended. Note that this adjustment may be performed after all parts have been assembled.

[0055] Next, the adjustment valve 50 is attached to the housing portion 15 of the throttle body 10. Specifically, the coil spring 52 is inserted into the housing portion 15, and then the valve body 51 is inserted into the housing portion 15 while connected to the electromagnetic actuator 53. Then, the retaining member 54 is joined to the end face of the housing portion 15 to fix the electromagnetic actuator 53, and fastened to the throttle body 10 with a screw b3.

[0056] Next, the sensor unit U is joined to the mounting surface 16 of the throttle body 10 and fastened with screws b1. That is, with the sealing member Sr2 fitted into the annular groove 65, the fitting portion 61 of the housing 60 is fitted into the annular recess 16b of the throttle body 10, and the joining surface 62 is joined to the mounting surface 16. Then, the housing 60 is fastened to the throttle body 10 with screws b1, and the sensor unit U is fixed to the throttle body 10.

[0057] As a result, the main passage 12 is in communication with the recess 63 downstream of the throttle valve 30 via a connecting passage 17 (first connecting passage 17a and second connecting passage 17b) that opens to the mounting surface 16. Here, the pressure sensor 80 and temperature sensor 90 are positioned to detect the pressure and temperature of the intake air guided into a recess 63 formed to recess out of the mating surface 62 of the housing 60, that is, they are positioned so as not to protrude from the mating surface 62. Therefore, the sensor unit U can be easily attached to the throttle body 10 without having to take care to ensure that the pressure sensor 80 and temperature sensor 90 do not interfere with other components. Furthermore, the assembly of the throttle device is not limited to the method described above; other methods may also be used.

[0058] Next, we will explain the operation of the throttle device when it is mounted on the engine. First, when the engine is in the idle operating range, the throttle valve 30 closes the main passage 12, and the intake air flowing through the main passage 12 flows through the bypass passage 14 to bypass the throttle valve 30 and then flows back into the main passage 12 downstream. In this state, the control valve 50 adjusts the passage area of ​​the bypass passage 14 (connecting passage 14c) to maintain a stable idle state for the engine.

[0059] On the other hand, when the engine is in an operating range other than the idle operating range, the throttle valve 30 is within a predetermined opening range, and the main passage 12 is open. Therefore, the intake air flowing through the main passage 12 is drawn into the engine without passing through the bypass passage 14. In this case, the control valve 50 is not used to adjust the amount of intake air flowing through the bypass passage 14.

[0060] Furthermore, as shown in Figure 13, the intake air flowing through the main passage 12 is guided into the recess 63 through the first connecting passage 17a or the second connecting passage 17b. In this state, the pressure sensor 80 detects the pressure of the intake air guided into the recess 63. The temperature sensor 90 also detects the temperature of the intake air guided into the recess 63. In this way, the intake pressure is detected by the pressure sensor 80, and the intake temperature is detected by the temperature sensor 90. The detected information is taken into the control unit as control information, and the engine is controlled accordingly.

[0061] The throttle device according to the first embodiment described above includes a throttle body 10 having a main passage 12 through which intake air passes, a mounting surface 16 formed on the outer wall, and a connecting passage 17 that opens to the mounting surface 16 and leads to the main passage 12; a throttle valve 30 that opens and closes the main passage 12; and a sensor unit U joined to the mounting surface 16. The sensor unit U includes a housing 60 having a joining surface 62 that is joined to the mounting surface 16 and a recess 63 that is recessed from the joining surface 62 and leads to the connecting passage 17; a circuit board 70 embedded in the housing 60; a pressure sensor 80 electrically connected to the circuit board 70 and detecting the pressure of the intake air led to the recess 63; and a temperature sensor 90 electrically connected to the circuit board 70 and detecting the temperature of the intake air led to the recess 63. According to this design, the sensor unit U houses the pressure sensor 80 and the temperature sensor 90 so that they do not protrude from the joint surface 62. In particular, interference between the temperature sensor 90 and external components can be prevented, thus preventing damage and allowing for miniaturization. Furthermore, the degree of freedom in mounting the sensor unit U to the throttle body 10 is improved, the moldability of the housing 60 is improved, and cost reduction can be achieved.

[0062] Furthermore, the communication passage 17 is formed to connect the main passage 12 and the recess 63 downstream of the throttle valve 30, and is also formed to include a first communication passage 17a and a second communication passage 17b that connect the recess 63 and the main passage 12, respectively. According to this, by utilizing the pulsation of the intake air, the intake air can be actively guided into the recess 63 and the intake air can be scavenged, and the intake air pressure and temperature can be detected with high precision.

[0063] Furthermore, the housing 60 includes an annular groove 65 formed in the joining surface 62 so as to surround the recess 63, and a sealing member Sr2 that is in close contact with the mounting surface 16 of the throttle body 10 is disposed in the annular groove 65. According to this, since it is only necessary to seal around one recess 63 facing the pressure sensor 80 and temperature sensor 90 with a single sealing member Sr2, it is possible to reduce the number of parts, lower costs, and simplify the housing 60 compared to a configuration in which the pressure sensor and temperature sensor are placed facing separate recesses and sealed with separate sealing members.

[0064] Furthermore, the pressure sensor 80 is positioned facing the recess 63 near the first communication passage 17a, and the temperature sensor 90 is positioned facing the recess 63 near the second communication passage 17b. According to this, by utilizing a scavenging action in which the intake air from the main passage 12 is guided to the recess 63 through the first connecting passage 17a, as shown by the solid arrow in Figure 13, and the intake air in the recess 63 is returned to the main passage 12 through the second connecting passage 17b, or by utilizing a reverse scavenging action in which the intake air from the main passage 12 is guided to the recess 63 through the second connecting passage 17b, as shown by the dotted arrow in Figure 13, and the intake air in the recess 63 is returned to the main passage 12 through the first connecting passage 17a, the intake air in the recess 63 can be prevented from stagnating, and the intake air pressure and temperature can be detected.

[0065] Furthermore, since the temperature sensor 90 is a leaded sensor connected to the circuit board 70 via lead wires 92, it can detect the intake air temperature in an area close to the recess 63. In particular, since the housing 60 includes a protruding wall 64 that protrudes within the recess 63, and the temperature sensor 90 is positioned so as to be covered by the protruding wall 64, it is possible to prevent carbon and other substances brought in by blowback of intake air from directly adhering to the temperature sensing element 91. This enables high-precision detection of the intake air temperature.

[0066] Figures 14 to 19 show a throttle device according to a second embodiment of the present invention, which is identical to the first embodiment except that the sensor unit U of the throttle device according to the first embodiment has been changed to a sensor unit U2. Therefore, the same reference numerals are used for identical components and their descriptions are omitted. The throttle device according to the second embodiment includes a throttle body 10, a valve shaft 20 having an axis S, a throttle valve 30, a drive unit 40 for opening and closing the throttle valve 30, a control valve 50, and a sensor unit U2. Here, the sensor unit U2 includes a housing 160, a circuit board 70, a pressure sensor 80, and a temperature sensor 190.

[0067] The housing 160 is molded from a resin material and includes a fitting portion 61, a joining surface 62, a recess 63, an annular groove 65, an outer housing recess 66, two boss portions 67 through which the screw b1 passes, a connector 68, a protective wall 164, an extension passage 165, and a cylindrical passage member M1.

[0068] As shown in Figures 15 and 16, the protective wall 164 is formed in a thin plate shape at a position deeper than the recess 63 from the joint surface 62, and is interposed between the temperature sensor 190 surface-mounted on the circuit board 70 and the extension passage 165, so as to cover the temperature sensor 190.

[0069] As shown in Figures 14, 16, and 18, the extension passage 165 is formed to extend from the recess 63 to the protective wall 164 at a position away from the small-diameter hole 83a facing the recess 63 and closer to the second connecting passage 17b. The passage member M1 is fitted in such a way that it occupies a portion of the extension passage 165, thereby dividing the extension passage 165 into a first extension passage 165a and a second extension passage 165b. In other words, the extension passage 165 is formed to include a first extension passage 165a defined around the passage member M1 and a second extension passage 165b defined by the passage member M1. Here, one end opening of the passage member M1 communicates with the second connecting passage 17b, and the other end opening of the passage member M1 faces the protective wall 164 with a gap region Ga between them.

[0070] As shown in Figure 17, the temperature sensor 190 is a chip-type sensor surface-mounted on the circuit board 70, such as a chip-type NTC thermistor. In this way, by adopting a chip-type sensor as a temperature sensor, miniaturization and cost reduction can be achieved.

[0071] In the above configuration, the extension passage 165 is formed as two passages, the first extension passage 165a and the second extension passage 165b. As shown by the dotted arrows in Figure 19, the intake air from the main passage 12 is guided through the second connecting passage 17b and the second extension passage 165b to the gap region Ga facing the protective wall 164, and from the gap region Ga is returned to the main passage 12 through the first extension passage 165a, the recess 63, and the first connecting passage 17a, resulting in a scavenging action. In addition, as shown by the solid arrows in Figure 19, the intake air from the main passage 12 is guided through the first connecting passage 17a, the recess 63, and the first extension passage 165a to the gap region Ga facing the protective wall 164, and from the gap region Ga is returned to the main passage 12 through the second extension passage 165b and the second connecting passage 17b, resulting in a reverse scavenging action.

[0072] In this way, the intake air from the main passage 12 can be guided to the gap region Ga near the protective wall 164. This allows the pressure sensor 80 to detect the intake air pressure with high accuracy, and the temperature sensor 190 to detect the intake air temperature with high accuracy. Furthermore, by employing the passage member M1 that defines the second extension passage 165b, the moldability of the housing 160 is improved. According to the throttle device of the second embodiment described above, similar to the first embodiment described above, it is possible to detect the intake pressure and temperature with high accuracy while achieving improved moldability, reduced costs, increased freedom in outfitting, miniaturization, and the like.

[0073] Figures 20 to 22 show a throttle device according to a third embodiment of the present invention, and are identical to the first and second embodiments except that the sensor unit U2 of the throttle device according to the second embodiment is changed to a sensor unit U3. Therefore, identical components are denoted by the same reference numerals and their descriptions are omitted. The throttle device according to the third embodiment includes a throttle body 10, a valve shaft 20 having an axis S, a throttle valve 30, a drive unit 40 for opening and closing the throttle valve 30, a control valve 50, and a sensor unit U3. Here, the sensor unit U3 includes a housing 260, a circuit board 70, a pressure sensor 80, and a temperature sensor 190.

[0074] The housing 260 is molded from a resin material and includes a fitting portion 61, a joining surface 62, a recess 63, an annular groove 65, an outer housing recess 66, two boss portions 67 through which the screw b1 passes, a connector 68, a protective wall 164, an extension passage 265, and a cylindrical passage member M2.

[0075] As shown in Figures 20 and 21, the extension passage 265 is formed to extend from the recess 63 to the protective wall 164 at a position away from the small-diameter hole 83a facing the recess 63 and closer to the second connecting passage 17b. The passage member M2 is fitted in such a way that it occupies a portion of the extension passage 265, thereby dividing the extension passage 265 into a first extension passage 265a and a second extension passage 265b. In other words, the extension passage 265 is formed to include a first extension passage 265a defined around the passage member M2 and a second extension passage 265b defined by the passage member M2. The second extension passage 265b is formed to include a straight passage 265b1 facing the protective wall 164 and a curved passage 265b2 interposed between the straight passage 265b1 and the second extension passage 17b. Here, one end opening of the passage member M2 (bent passage 265b2) communicates with the second connecting passage 17b, and the other end opening of the passage member M2 (straight passage 265b1) faces the protective wall 164 with a gap region Ga between them.

[0076] In the above configuration, the extension passage 265 is formed as two passages, the first extension passage 265a and the second extension passage 265b. As shown by the dotted arrows in Figure 22, the intake air from the main passage 12 is guided through the second connecting passage 17b and the second extension passage 265b to the gap region Ga facing the protective wall 164, and from the gap region Ga is returned to the main passage 12 through the first extension passage 265a, the recess 63, and the first connecting passage 17a, resulting in a scavenging action. In addition, as shown by the solid arrows in Figure 22, the intake air from the main passage 12 is guided through the first connecting passage 17a, the recess 63, and the first extension passage 265a to the gap region Ga facing the protective wall 164, and from the gap region Ga is returned to the main passage 12 through the second extension passage 265b and the second connecting passage 17b, resulting in a reverse scavenging action.

[0077] In particular, since the second extension passage 265b is formed to include a bent passage 265b2, if carbon or the like is present in the intake air guided from the main passage 12 through the second connecting passage 17b, the carbon or the like can be captured in the bent passage 265b2 and prevented from entering the gap region Ga. On the other hand, if carbon or the like is present in the intake air guided from the main passage 12 through the first connecting passage 17a, the passage leading from the recess 63 to the first extension passage 265a forms a bent passage, so the carbon or the like can be captured in the region of the recess 63 and prevented from entering the gap region Ga.

[0078] In this way, the intake air from the main passage 12 can be guided to the gap region Ga near the protective wall 164. This allows the pressure sensor 80 to detect the intake air pressure with high accuracy, and the temperature sensor 190 to detect the intake air temperature with high accuracy. Furthermore, by employing the passage member M2 that defines the second extension passage 265b, the moldability of the housing 260 is improved, as described above. According to the throttle device of the third embodiment described above, similar to the first and second embodiments described above, it is possible to detect the intake pressure and temperature with high accuracy while achieving improved moldability, reduced costs, increased freedom in outfitting, miniaturization, and the like.

[0079] In the above embodiment, sensor units U, U2, and U3 equipped with a pressure sensor 80 and temperature sensors 90 and 190 were shown as sensor units, but the invention is not limited to this, and may further include a position detection sensor for detecting the rotation angle of the valve shaft 20. In this case, a non-contact magnetic sensor, including a Hall element or the like, embedded in the inner region of the mating portion 61, may be used as the position detection sensor.

[0080] In the above embodiment, a configuration was shown in which two passages (first extension passages 165a, 265a and second extension passages 165b, 265b) are defined by fitting passage members M1 and M2 into one extension passage 165, 265 as an extension passage extending from the recess 63 to the protective wall 164. However, the invention is not limited to this configuration, and if permitted in the manufacturing of the housing, the passage members M1 and M2 may be eliminated, and two passages (first extension passage and second extension passage) may be directly formed in the housing.

[0081] In the above embodiment, the configuration is shown in which one end opening of the passage members M1 and M2 leads to the second connecting passage 17b, but the configuration is not limited to this, and it may be configured to lead to the recess 63 in the vicinity of the second connecting passage 17b. Specifically, the extension passage may be configured to include a first extension passage and a second extension passage, with the first extension passage defined around the passage members M1 and M2 configured in the same manner as described above, and the opening at one end of the second extension passage defined by the passage members M1 and M2 not directly leading to the second connecting passage 17b, but opening into the recess 63, and leading to the second connecting passage 17b via the recess 63.

[0082] In the above embodiment, a configuration including two passages (first extension passages 165a, 265a and second extension passages 165b, 265b) is shown as an extension passage extending from the recess 63 to the protective wall 164, but the invention is not limited to this. For example, if intake air can be easily introduced to the vicinity of the protective wall 164 by a single extension passage, a single extension passage may be used as the extension passage extending from the recess 63 to the protective wall 164.

[0083] In the above embodiment, a connecting passage 17 including a first connecting passage 17a and a second connecting passage 17b was shown as a connecting passage that opens to the mounting surface 16 and leads to the main passage 12. However, the embodiment is not limited to this, and a single connecting passage may be used as long as a configuration is available in which a scavenging action can be easily obtained in which the intake air from the main passage 12 is guided to the recess 63 and the intake air in the recess 63 is returned to the main passage 12.

[0084] As described above, the throttle device of the present invention can detect intake air temperature and pressure with high accuracy while achieving improved moldability, lower costs, greater freedom in outfitting, and miniaturization. Therefore, it is not only applicable to motorcycles and the like, but is also useful in other vehicles. [Explanation of symbols]

[0085] 10 Throttle Body 12 Main aisle 14 Bypass passage 16 Mounting surface 17 Communication path 17a 1st communication passage 17b 2nd communication passage 20 Valve stem 30 Throttle valve 40 Drive Unit 50 Adjustment valve U Sensor Unit R resin encapsulant 60 Housing 62 Joint surface 63 recess 64 Projecting wall 65 Annular groove Sr2 sealing component 70 Circuit boards 80 Pressure Sensor 90 Temperature Sensor (Lead Type Sensor) 91 Temperature sensing element 92 Lead wires U2 Sensor Unit 160 Housing 164 Protective Wall 165 Extension passage M1 Passageway Member 165a 1st extension passage 165b 2nd extension passage 190 Temperature Sensor (Chip-type Sensor) U3 Sensor Unit 260 Housing 265 Extension passage M2 passage member 265a 1st extension passage 265b 2nd extension passage 265b1 straight passage 265b2 curved passage

Claims

1. A throttle body having a main passage for intake air, a mounting surface formed on the outer wall, and a connecting passage that opens to the mounting surface and leads to the main passage, A throttle valve that opens and closes the main passage, The system comprises a sensor unit joined to the mounting surface, The sensor unit includes a housing having a bonding surface that is bonded to the mounting surface and a recess that is recessed from the bonding surface and leads to the communication passage, a circuit board embedded in the housing, a pressure sensor electrically connected to the circuit board and used to detect the pressure of intake air guided to the recess, and a temperature sensor electrically connected to the circuit board and used to detect the temperature of intake air guided to the recess. The aforementioned connecting passage includes a first connecting passage and a second connecting passage that connect the recess and the main passage, respectively. The pressure sensor is positioned so as to face the recess near the first communication passage, The temperature sensor is positioned so as to face the recess near the second communication passage. A throttle device characterized by the following features.

2. The aforementioned communication passage connects the recess to the downstream side of the main passage from the throttle valve. The throttle device according to feature 1.

3. The housing includes an annular groove formed on the joint surface so as to surround the recess, A sealing member is disposed in the annular groove, which is in close contact with the mounting surface of the throttle body. The throttle device according to feature 2.

4. A bypass passage that branches off from the main passage, introduces intake air, bypasses the throttle valve, and leads the intake air back to the main passage, Includes a control valve for adjusting the passage area of ​​the bypass passage, The throttle device according to claim 3.

5. The temperature sensor is a leaded sensor connected to the circuit board via lead wires. The throttle device according to feature 1.

6. The housing includes a protruding wall that protrudes within the recess, The temperature sensor is covered by the protruding wall. The throttle device according to feature 5.

7. A throttle body having a main passage for intake air, a mounting surface formed on the outer wall, and a connecting passage opening to the mounting surface and leading to the main passage, A throttle valve that opens and closes the main passage, The system comprises a sensor unit joined to the mounting surface, The sensor unit includes a housing having a bonding surface that is bonded to the mounting surface and a recess that is recessed from the bonding surface and leads to the communication passage, a circuit board embedded in the housing, a pressure sensor electrically connected to the circuit board and used to detect the pressure of intake air guided to the recess, and a temperature sensor electrically connected to the circuit board and used to detect the temperature of intake air guided to the recess. The aforementioned connecting passage includes a first connecting passage and a second connecting passage that connect the recess and the main passage, respectively. The temperature sensor is a chip-type sensor surface-mounted on the circuit board. The housing includes a protective wall formed at a position deeper than the recess from the joint surface, and an extension passage extending from the recess to the protective wall. The temperature sensor is covered by the protective wall. A throttle device characterized by the following features.

8. The extension passage includes a first extension passage and a second extension passage. The throttle device according to feature 7.

9. Including a passage member fitted into the housing to define the second extension passage, The throttle device according to feature 8.

10. The first extension passage leads to the recess, The second extension passage leads to the second connecting passage. The throttle device according to feature 8.

11. The second extension passage includes a straight passage facing the protective wall and a curved passage interposed between the straight passage and the second extension passage. The throttle device according to feature 10.

12. Including a passage member fitted into the housing to define the second extension passage, The throttle device according to feature 11.

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