JP5950203B2 - Engine intake air amount control device - Google Patents

Description

  In the present invention, a valve guide hole and a metering hole that opens on the inner surface of the valve guide hole and through which the intake air of the engine passes are formed in the control base. A control valve for opening and closing the metering hole is slidably and non-rotatably fitted, and a screw mechanism is provided on the control valve so that the output shaft of the electric motor attached to the control base can be rotated forward and backward. The screw mechanism is connected to the control valve via a detent means, and a slide piece that synchronously opens and closes the control valve, and is connected to the output shaft. The present invention relates to an improvement in an intake air amount control device for an engine, which includes a screw shaft that is screwed into a screw hole provided along the sliding direction of the control valve.

  Such an intake control device for an engine is already known as disclosed in Patent Document 1 below.

JP 2009-114997 A

  In a conventional engine intake air amount control device, a gap is created between the inner surface of the valve guide hole where the metering hole opens and the outer surface of the control valve that opens and closes the metering hole due to manufacturing and assembly errors. Due to intake air leakage from the gap, the intake air amount of the engine may vary, particularly when the control valve is fully closed or partially opened.

The present invention has been made in view of such circumstances. The control valve for opening and closing the measuring hole and the inner surface of the valve guide hole in which the measuring hole opens without being substantially affected by manufacturing errors and assembly errors. always in close contact with the outer surface of, during which in the no space, air intake of the engine so as to be fully closed and partially opening when odor control valves can properly control the intake air amount of the engine An object is to provide a quantity control device.

In order to achieve the above object, the present invention forms a valve guide hole in the control base and a metering hole that opens on the inner surface of the valve guide hole and through which the intake air of the engine passes, A control valve that opens and closes the metering hole is fitted in the valve guide hole so as to be slidable and non-rotatable. A forward / reverse rotation of an electric motor attached to the control base body is driven to open and close the control valve. A possible output shaft is connected via a screw mechanism, and the screw mechanism is connected to the control valve via a detent means to synchronously open and close the control valve, and to the output shaft. In an engine intake air amount control device comprising a screw shaft that is provided in series and is screwed into a screw hole provided in the slide piece along the sliding direction of the control valve.
A control inner surface is formed on the inner surface of the valve guide hole, and the metering hole is opened on the control inner surface, while a control outer surface that is in sliding contact with the control inner surface is formed on the outer surface of the control valve. ,
The anti-rotation means is arranged on the first and second pressure parts provided in the slide piece so as to be arranged along the rotation direction of the screw shaft, and on the first and second pressure parts in the rotation direction of the screw shaft. The control valve includes first and second pressure receiving portions provided in the control valve so as to face each other, and the first pressure receiving portion presses the first pressure receiving portion during forward rotation of the screw shaft. The slide piece is pressed so that the outer side surface is in close contact with the control inner side surface, and the second pressurizing unit presses the second pressure receiving unit during reverse rotation of the screw shaft, thereby The first feature is that the slide piece is pressed so as to be in close contact with the inner surface of the control.

  According to the present invention, in addition to the first feature, the first and second pressure parts are formed integrally with the slide piece, and the first and second pressure receiving parts are formed integrally with the control valve. Is the second feature.

  In addition to the second feature of the present invention, the control valve includes a control wall having an outer surface as the control outer surface, and a front end standing upright from a front end portion of the control wall opposite to the electric motor. The slide piece is disposed in the control valve so that the front end surface thereof faces the front end wall, and the first and second pressure receiving portions are erected from the inner surface side of the control wall. A common pressure receiving protrusion formed integrally on the inner surface of the front end wall, and the first and second pressure portions are arranged in a V shape so as to sandwich the pressure receiving protrusion therebetween, and It is formed integrally with the front end surface, and acts on the pressure receiving projections when the first pressure member presses the first pressure receiver and when the second pressure member presses the second pressure receiver. Before the component force brings the control outer surface into close contact with the control inner surface. That presses the slide piece and third features.

  Furthermore, in addition to the third feature of the present invention, the fourth feature is that the opening angle of the pressurizing surface arranged in the V shape of the first and second pressurizing portions is set to 90 ° or more. .

  In addition to the third or fourth feature of the present invention, a first spring seat is provided at the front end of the slide piece, and a second spring seat facing the first spring seat is provided at the rear end of the control valve. Between the first and second spring seats, the control valve is urged rearward with respect to the slide piece, and the first and second pressure-receiving portions and the first and second pressure-receiving portions are A fifth feature is that the coil spring that holds the facing position is contracted.

According to the first aspect of the present invention, the control inner surface is formed on the inner surface of the valve guide hole, the metering hole is opened on the control inner surface, and the control inner surface is formed on the outer surface of the control valve. First and second pressurizing portions that form a control outer surface that is in sliding contact, and that are provided on the slide piece so that the rotation prevention means between the control valve and the slide piece is arranged along the rotation direction of the screw shaft, The first and second pressure receiving portions are respectively opposed to the first and second pressure portions in the rotation direction of the shaft, and the first pressure portion presses the first pressure receiving portion during the forward rotation of the screw shaft. Thus, the slide piece is pressed so that the control outer surface of the control valve is in close contact with the control inner surface of the valve guide hole, and the second pressurizing portion presses the second pressure receiving portion when the screw shaft is reversely rotated. To close the outer surface of the control to the inner surface of the control Since the slide piece is pressed, the control valve is controlled in the valve guide hole by the pressing force applied to the corresponding pressure receiving portion by either the first or second pressurizing portion, regardless of whether the output shaft is rotating forward or reverse. Pressed against the control inner surface, the control outer surface is brought into close contact with the control inner surface of the valve guide hole, and the clearance between the control inner surface and the control outer surface can be eliminated. by opening and closing the opening for metering holes in the control side, the leakage of the intake air due to a gap between the valve guide hole and the control valve without score and can, therefore even when fully closed or partial opening of the control valve, the An appropriate amount of bypass intake corresponding to the opening can be supplied to the engine.

  According to the second feature of the present invention, the first and second pressure parts are formed integrally with the slide piece, and the first and second pressure receiving parts are formed integrally with the control valve. The number of parts is not increased by the means, and the structure of the intake air amount control device can be simplified.

  According to the third feature of the present invention, the control valve is provided with a control wall having an outer surface as a control outer surface and a front end wall standing up from a front end portion of the control wall opposite to the electric motor. The slide piece is disposed in the control valve so that the front end surface thereof faces the front end wall, and a common pressure receiving protrusion having first and second pressure receiving portions standing from the inner surface side of the control wall is disposed on the front end wall. The first and second pressurizing parts are integrally formed on the front end surface of the slide piece while being arranged in a V shape so that the pressure receiving protrusion is sandwiched between them. Whether the part presses the first pressure receiving part or the second pressure pressing part presses the second pressure receiving part, the component force acting on the pressure receiving projection slides so that the control outer surface is in close contact with the control inner surface. Since the piece is pressed, the front end wall of the control valve and the sleeve accommodated in the control valve Between the front end surface of Idopisu, said detent means can be made compact, it is possible to avoid an increase in size of the intake air amount control device.

  According to the fourth feature of the present invention, since the V-shaped opening angle between the first and second pressure parts is set to 90 ° or more, the space between the first and second pressure parts opposed to each other. Can be easily formed by cutting the material of the slide piece with an end mill.

  According to the fifth feature of the present invention, a first spring seat is provided at the front end of the slide piece, and a second spring seat opposite to the first spring seat is provided at the rear end of the control valve. Since the control valve is urged rearward with respect to the slide piece between the second spring seats, the coil spring that holds the opposed positions of the first and second pressure members and the first and second pressure receivers is contracted. By connecting the slide piece and the control valve in the axial direction with a coil spring without any backlash, the control valve can be synchronized with the axial movement of the slide piece without delay.

1 is a longitudinal side view of an intake air amount control device for an engine according to a first embodiment of the present invention. FIG. 2 is an enlarged sectional view taken along line 2-2 in FIG. 1. FIG. 3 is a cross-sectional view taken along line 3-3 of FIG. FIG. 4 is a view corresponding to FIG. 3 showing a second embodiment of the present invention.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  First, the description starts with the description of the first embodiment of the present invention shown in FIGS. In FIG. 1, reference numeral 1 denotes a throttle body attached to an engine for a motorcycle, for example, which has an intake passage 2 that communicates with an intake port of the engine at the center and is a butterfly type that opens and closes the intake passage 2. A throttle valve 3 is pivotally supported on the throttle body 1. A support base 4 is integrally formed on the upper side wall of the throttle body 1, and a control base 5 is superimposed on the support base 4 and fastened by a bolt (not shown).

  1 to 3, the control base 5 is formed with a bottomed cylindrical valve guide hole 7. The valve guide hole 7 has a polygonal cross section (see FIG. 3, square in the illustrated example). The lower inner surface of the valve guide hole 7 along the direction of gravity is a control inner surface 8a. The control base 5 is provided with a measuring hole 10 that opens to the control inner side surface 8 a and an inlet hole 11 that opens to the control inner side surface 8 a on the bottom side of the valve guide hole 7 from the measuring hole 10. The measuring hole 10 has a long hole shape whose long diameter is arranged along the axial direction of the valve guide hole 7, and a control valve 12 for opening and closing the measuring hole 10 is slidably fitted in the valve guide hole 7. Is done.

  On the other hand, in the throttle body 1, a bypass upstream passage 14 connecting the intake passage 2 upstream from the throttle valve 3 to the inlet hole 11 and the metering hole 10 are connected to the intake passage 2 downstream from the throttle valve 3. A bypass downstream passage 15 is provided. Between the joint surfaces of the throttle body 1 and the control base 5, there are interposed seal members 16 surrounding the connecting portion between the bypass upstream passage 14 and the inlet hole 11 and the connecting portion between the bypass downstream passage 15 and the measuring hole 10, respectively. Be dressed. Thus, the bypass upstream passage 14, the inlet hole 11, the valve guide hole 7, the metering hole 10 and the bypass downstream passage 15 constitute a bypass 17 that bypasses the throttle valve 3 and is connected to the intake passage 2.

The control valve 12 is erected from a control wall 12a slidably contacting the control inner side surface 8a of the valve guide hole 7 with the lower side surface as a control outer side surface 8b, and the valve guide hole 7 A pair of side walls 12b, 12b facing both the left and right inner side surfaces, and a front end wall 12c standing up from the front end of the control wall 12a on the bottom side of the valve guide hole 7 and connecting between the front end portions of the side walls 12b, 12b , A control wall 12a and a U-shaped inward ridge 12d projecting inwardly from the rear end of both side walls 12b, 12b , and a box shape having an open surface 12e on the surface opposite to the control wall 12a Therefore, the control valve 12 is slidable in the axial direction in the valve guide hole 7 having a square cross section, but cannot rotate.

  The control base 5 is provided with a motor mounting hole 19 having a diameter larger than that of the valve guide hole 7, which is connected to the opening end of the valve guide hole 7 via a step portion 18, and a stator 20 a of the electric motor 20 is mounted on the control base 5. . At that time, a seal member 21 that is in close contact with the outer peripheral surface of the output shaft 20 b of the electric motor 20 is sandwiched between the front end surface of the stator 20 a and the step portion 18. The output shaft 20b of the electric motor 20 can be rotated forward and backward, and the control valve 12 is connected to the output shaft 20b via a screw mechanism 25.

  The screw mechanism 25 is connected to the control valve 12 via a detent means 26 and is connected to the slide piece 27 that synchronously opens and closes the control valve 12 and the output shaft 20 b of the electric motor 20. The screw shaft 29 is screwed into a screw hole 28 provided along the sliding direction of the control valve 12. The screw hole 28 is formed in a bag shape having a dead end portion 28a. The slide piece 27 is formed on the outer periphery of a cylindrical shaft 27a that passes through the U-shaped inward flange 12d of the control valve 12 and is disposed in the control valve 12, and a closed end wall 27b at the front end of the cylindrical shaft 27a. The cylindrical shaft 27a is provided with a bag-like screw hole 28 into which the screw shaft 29 is screwed. The cylindrical shaft 27a has a pair of coaxial holes 30 in the vicinity of the dead end portion 28a of the screw hole 28 so that the screw hole 28 is opened to both opposing surfaces on the outer periphery of the cylindrical shaft 27a and parallel to the open surface 12e of the control valve 12. 30 is provided.

The first spring seat 31 on the inner surface of the outward flange 27c is also on the inner surface of the inward flange 12d is formed a second spring seat 32, respectively, the coil spring 33 between the both Sprint grayed seats 31, 32 Due to the set load of the coil spring 33, the control valve 12 is urged rearward, that is, toward the electric motor 20 with respect to the slide piece 27, so that the front end wall 12c of the slide piece 27 is in contact with the outward flange 27c. The contact state is maintained. Thereby, the slide piece 27 and the control valve 12 are connected to each other without backlash in the axial direction.

  The coil spring 33 is integrally connected to the tightly wound portion 33a that is fitted to the outer peripheral portion of the cylindrical shaft 27a in which the lateral holes 30 and 30 are bored while being supported by the first spring seat 31. And a cone spring portion 33b having a larger diameter than the tightly wound portion 33a and having a large diameter end portion 33b1 supported by the control valve 12. The tightly wound portion 33a is an outer end of the lateral holes 30 and 30. The opening is closed.

As shown in FIGS. 2 and 3, the anti-rotation means 26 includes a pressure protrusion 35 that integrally projects from the outer end surface of the closed end wall 27 b with the flange 27 c of the slide piece 27, and the control valve 12. A pressure receiving projection 36 is provided on the inner surface of the front end wall 12c so as to stand up from the inner surface of the wall 12a. The pressure protrusion 35 includes first and second pressure portions 35a having a pair of pressure surfaces 35a1 and 35b1 arranged in a V shape so as to sandwich the pressure receiving protrusion 36 along the rotation direction of the screw shaft 29. 35b is provided, and the opening angle θ between the pair of pressure surfaces 35a1 and 35b1 arranged in the V shape is set to 90 ° or more. If it carries out like this, the pressurization surfaces 35a1 and 35b1 of the 1st and 2nd pressurization parts 35a and 35b which mutually oppose can be processed easily by an end mill.

  On the other hand, the pressure receiving projection 36 is provided with convex first and second pressure receiving portions 36a, 36b facing the pressure surfaces 35a1, 35b1, respectively.

  Next, the operation of the first embodiment will be described.

When the throttle valve 3 is fully closed, an electronic control unit (not shown) starts up the engine based on information on the engine operating conditions such as throttle valve opening, engine intake negative pressure, intake air temperature, engine temperature, and engine speed. , during fast idling, during normal idling, such as during engine braking, to Ru get the best opening of the control valve 12 corresponding to the operating condition of the engine, by controlling the power supply to the electric motor 20, the output shaft of the electric motor 20 20b is rotated forward or reverse. When the output shaft 20b rotates or reversely rotates, the rotation is transmitted to the control valve 12 via the slide piece 27 while being decelerated by the screw mechanism. The opening area to the valve guide hole 7 can be finely adjusted. Thus, the intake air amount of the engine flowing through the bypass 17 is finely controlled, and it is possible to cope with engine start, fast idling, normal idling, engine braking, and the like.

By the way, as shown in FIG. 3A, when the output shaft 20b of the electric motor 20 is rotated forward, the forward rotation torque T1 of the output shaft 20b is applied to the slide piece 27 via the friction between the screw shaft 29 and the screw hole 28. Then, the pressurizing surface 35a1 of the first pressurizing portion 35a presses the first pressure receiving portion 36a obliquely against the control inner surface 8a of the valve guide hole 7. Accordingly, the pressing force F applied to the first pressure receiving portion 36a is decomposed into a first component force perpendicular to the control inner surface 8a and a second component force F2 parallel to the control inner surface 8a, and the first component force F1. The control valve 12 is pressed against the control inner surface 8a, and the second component force F2 presses the control valve 12 against one inner surface of the valve guide hole 7. As shown in FIG. 3B, when the output shaft 20b of the electric motor 20 is reversely rotated, the reverse rotation torque T2 of the output shaft 20b is transmitted to the slide piece 27 via the friction between the screw shaft 29 and the screw hole 28. The pressurizing surface 35b1 of the second pressurizing portion 35b presses the second pressure receiving portion 36b against the control inner side surface 8a of the valve guide hole 7 in an oblique direction opposite to the previous time. Accordingly, the pressing force F applied to the second pressure receiving portion 36b is divided into a first component force perpendicular to the control inner surface 8a and a second component force F2 parallel to the control inner surface 8a, and the first component force F1 is controlled. The valve 12 is pressed against the control inner surface 8a, and the second component force F2 presses the control valve 12 against the other inner surface of the valve guide hole 7.

Thus, since the control valve 12 is pressed against the control inner surface 8a side of the valve guide hole 7 by the first component force F1 in both the forward rotation and the reverse rotation of the output shaft 20b, the control outer surface 8b. Can be brought into close contact with the control inner surface 8 a of the valve guide hole 7. That is, a gap can be eliminated from between the control inner side surface 8a and the control outer side surface 8b, and in this state, the control valve 12 opens and closes the measuring hole 10 opened to the control inner side surface 8a. 7 and by the gap between the control valve 12 can and score without leakage of the intake air, thus even when fully closed or partial opening of the control valve 12, supplies the proper bypass intake air quantity corresponding to the opening in the engine be able to. Moreover, the measuring hole 10 opened and closed by the control valve 12 has a long hole shape in which the long diameter is directed in the sliding direction of the control valve 12, so that the effective opening area is finely adjusted according to the sliding of the control valve 12. Can be adjusted.

  In this case, the control valve 12 is simultaneously subjected to a pressing force toward the control inner surface 8a due to gravity and a suction force due to the intake negative pressure of the engine acting on the control outer surface 8b of the control valve 12 from the measuring hole 10, By these, the adhesion force between the control outer side surface 8b and the control inner side surface 8a is further strengthened.

  The screw shaft 29 of the screw mechanism 25 pulls the slide piece 27 rearward, and the tip end portion of the screw mechanism 29 abuts against the dead end portion 28a of the screw hole 28 of the slide piece 27. Is regulated, and the measuring hole 10 is fully opened. This fully open position becomes the reference position of the control valve 12, the closing position of the control valve 12 is determined by the rotation angle of the output shaft 20b of the electric motor 20 from this reference position, and the opening degree of the measuring hole 10 is controlled.

  If the throttle valve 3 is opened, an amount of intake air corresponding to the opening degree is supplied to the engine through the intake passage 2, and the engine moves to the output operation range.

  By the way, the slide piece 27 and the control valve 12 are connected to each other in the axial direction by the coil spring 33, and the control valve 12 can follow the movement of the slide piece 27 in the axial direction without delay.

  In addition, the rotation preventing means 26 for connecting the slide piece 27 and the control valve 12 includes a pressure protrusion 35 that is integrally projected on the outer end surface of the closed end wall 27 b with the flange 27 c of the slide piece 27, and the control valve 12. The pressure receiving projection 36 is provided on the inner surface of the front end wall 12c so as to stand up from the inner surface of the control wall 12a. This can contribute to simplification of the structure. In addition, the rotation prevention means 26 can be configured compactly between the front end wall 12c of the control valve 12 and the outer end surface of the closed end wall 27b of the slide piece 27 accommodated in the control valve 12. An increase in the size of the quantity control device can be avoided.

  Further, when the screw hole 28 into which the screw shaft 29 is screwed is machined into the slide piece 27, first, the pilot hole of the screw hole 28 is first formed, and then a pair of coaxial holes 30 so as to cross the lower hole. , 30 is drilled, and then the screw hole is reamed into the lower hole. By doing so, the horizontal holes 30 and 30 cut the burrs (working residue) due to processing, and the screw hole 28 is insufficiently processed. Not only can be surely prevented, but also the chips generated at that time can be smoothly discharged from the horizontal holes 30 and 30, and when the screw hole 28 is washed, the remaining chips are removed by a pair of coaxial Since it can discharge | emit smoothly from the holes 30 and 30, the highly accurate screw hole 28 can be obtained. Further, the dead end portion 28a can be constituted by the bottom portion of the lower hole of the screw hole 28, and the structure can be simplified. In addition, if the horizontal holes 30 and 30 are formed larger in diameter than the lower hole, the cutting effect and discharging effect of the burr can be enhanced.

Further, a coil spring 33 arranged so as to surround the cylindrical shaft 27a of the slide piece 27 so as to connect the slide piece 27 and the control valve 12 in the axial direction is closed by the slide piece 27 so as to close the lateral holes 30 and 30. The tightly wound portion 33a whose end is supported by the first spring seat 31 of the slide piece 27 while being fitted to the outer peripheral surface of the slide piece 27, and the second spring seat 32 of the control valve 12 having a larger diameter than the tightly wound portion 33a. Since the cone spring portion 33b having the large-diameter end portion 33b1 to be supported is configured, the large-diameter end portion 33b1 of the coil spring 33 stabilizes the posture of the coil spring 33 in the control valve 12, and the tightly wound portion. 33a can prevent the dust that has entered the control valve 12 from entering the horizontal holes 30 and 30, and the horizontal holes Since 0 and 30 are arranged in parallel with the open surface 12e of the control valve 12, dust entering from the open surface 12e does not go directly to the lateral holes 30 and 30 and contributes to preventing dust from entering the screw hole 28. Can do. Therefore, without it an accompanied an increase in the number of parts and assembling steps, it prevents it from entering the threaded portion of the screw hole 28 and screw shaft 29 of the dust, smooth operation of the screw mechanism 25 is ensured.

  Further, since the tip end of the screw shaft 29 is brought into contact with the dead end portion, the fully open position as the reference position of the control valve is regulated, so that the screw shaft 29 is applied to the dead end portion 28a of the screw hole 28. By utilizing this, the reference position of the control valve 12 can be easily set, and no additional member is required for the setting, which can contribute to simplification of the structure.

  When assembling the intake air amount control device, first, the slide piece 27 fitted with the coil spring 33 is housed in the control valve 12 from the open surface 12e while the coil spring 33 is contracted, and the pressure protrusion of the slide piece 27 is accommodated. 35 is engaged with the pressure receiving projection 36 of the control valve 12, and at the same time, the coil spring 33 is released and the cone spring portion 33 b is supported on the second spring seat 32 of the control valve 12.

  Next, the screw shaft 29 on the electric motor 20 side is screwed into the screw hole 28 of the slide piece 27 to constitute an assembly of the electric motor 20 and the control valve 12. Alternatively, the screw shaft 29 may be first screwed into the screw hole 28 of the slide piece 27, and then the slide piece 27 may be housed in the control valve 12 together with the coil spring 33 from the open surface 12e. In any case, the slide piece 27 and the coil spring 33 can be easily assembled into the control valve 12 by using the open surface 12e of the control valve 12.

  Next, the control valve 12 is fitted into the valve guide hole 7 of the control base 5. At this time, since the open surface 12e of the control valve 12 is closed at the upper surface of the valve guide hole 7, the detachment of the slide piece 27 from the open surface 12e of the control valve 12 can be prevented. No special detachment prevention means is required, so that the assembly can be improved and the structure can be simplified. In addition, the accommodating space in the box-shaped control valve 12 whose upper surface is the open surface 12e has a wide cross section by the amount that the upper surface is the open surface 12e. Therefore, the control valve 12 can be made compact. However, the coil spring 33 and the slide piece 27 can be easily accommodated in the accommodation space.

  Subsequently, after the electric motor 20 is fitted in the motor mounting hole 19 of the control base 5, the electric motor 20 is fastened to the control base 5 with bolts (not shown).

Moreover since the cross section of the control valve 12 and the valve guide hole 7 has a polygonal shape, it prevents the rotation of the control valve 12 without using a special detent means, such as keys and keyways, with stable screw mechanism 25 Actuation can be obtained.

  Next, a second embodiment of the present invention shown in FIG. 4 will be described.

  In the second embodiment, the valve guide hole 7 and the control valve 12 are formed so that the cross-section is an isosceles trapezoid, and the control inner side surface 8a and the control outer side surface 8b are arranged on the lower bottom of each. Except for this, the configuration is the same as that of the previous embodiment. In FIG.

According to the second embodiment, when the output shaft 20b is rotated forward or reverse, any one of the first and second pressure members 35a and 35b is pressed against the corresponding first pressure member 36a or second pressure member 36b. When the pressure F is applied, the second component force F2 parallel to the control inner surface 8a generated in the first pressure receiving portion 36a or the second pressure receiving portion 36b causes the control valve 12 to move to either the left or right inner surface of the valve guide hole 7. However, since the inner surface of the inner surface is inclined inward, the reaction force toward the control inner surface 8a is generated on the control valve 12 when receiving the second component force F2. As a result, the control outer surface 8b of the control valve 12 is more closely attached to the control inner surface 8a, and the effect of eliminating the gap between the control inner surface 8a and the control outer surface 8b can be enhanced. .

  The present invention is not limited to the above embodiment, and various design changes can be made without departing from the scope of the invention. For example, instead of the electric motor 20, a step motor or other types of motors can be used. Further, the reference position of the control valve 12 when the tip of the screw shaft 29 hits the dead end portion 28a of the screw hole 28 can be set to the fully closed position of the control valve 12. The entire cone spring portion 33b of the coil spring 33 can be formed in a cylindrical shape having the same diameter as the large-diameter end portion 33b1.

5... Control body 7... Valve guide hole 8 a... Control inside surface 8 b... Control outside surface 10. · Control wall 12c ··· Front end wall 20 ··· Electric motor 20b · · · Output shaft 25 · · · Screw mechanism 26 · · · Anti-rotation means 27 · · · Slide piece 28 · · · Screw Hole 29 ... Screw shaft 31 ... First spring seat 32 ... Second spring seat 33 ... Coil spring 35 ... Pressing protrusion 35a ... First pressurizing part 35a1 ··· Pressure surface 35b ··· Second pressure portion 35b1 · · Pressure surface 36 ··· Pressure receiving protrusion 36a · · · First pressure receiving portion 36b · · · 2 pressure receiving portion

Claims (5)

The control base (5) has a valve guide hole (7) and a metering hole (10) that opens on the inner surface of the valve guide hole (7) and through which the intake air of the engine passes. In the valve guide hole (7), a control valve (12) for opening and closing the measuring hole (10) is slidably and non-rotatably fitted, and the control valve (12) is opened and closed. In order to drive, an output shaft (20b) of the electric motor (20) attached to the control base (5) is connected via a screw mechanism (25), and the screw mechanism (25) A slide piece (27) connected to the control valve (12) via a detent means (26) for synchronously opening and closing the control valve (12), and connected to the output shaft (20b), The control piece is attached to the slide piece (27). It constituted de Bed (12) a screw shaft screwed into the threaded hole (28) provided along the sliding direction of the (29), the intake air amount control device for an engine,
A control inner surface (8a) is formed on the inner surface of the valve guide hole (7), and the metering hole (10) is opened on the control inner surface (8a), while the outer surface of the control valve (12). And forming a control outer surface (8b) in sliding contact with the control inner surface (8a),
First and second pressurizing portions (35a, 35b) provided on the slide piece (27) so that the rotation preventing means (26) are arranged along the rotational direction of the screw shaft (29), and the screw shaft The first and second pressure receiving portions (36a, 36b) provided in the control valve (12) so as to face the first and second pressurizing portions (35a, 35b) in the rotational direction of (29), respectively. And
The first pressurizing portion (35a) presses the first pressure receiving portion (36a) during normal rotation of the screw shaft (29), thereby causing the control outer surface (8b) to move to the control inner surface (8a). Press the slide piece (27) so that it is in close contact with
The second pressurizing part (35b) presses the second pressure receiving part (36b) when the screw shaft (29) is reversely rotated, thereby causing the control outer surface (8b) to move to the control inner surface (8a). An intake air amount control device for an engine, wherein the slide piece (27) is pressed so as to be in close contact with the engine. The intake air amount control device for an engine according to claim 1,
The first and second pressure members (35a, 35b) are formed integrally with the slide piece (27), and the first and second pressure receivers (36a, 36b) are integrated with the control valve (12). An intake air amount control device for an engine characterized by being formed. The intake air amount control device for an engine according to claim 2,
The control valve (12) is erected from a control wall (12a) whose outer surface is the control outer surface (8b), and a front end of the control wall (12a) opposite to the electric motor (20). The slide piece (27) is disposed in the control valve (12) so that the front end surface thereof faces the front end wall (12c), and the control wall (12a) is provided. ) Is integrally formed on the inner surface of the front end wall (12c), and the first and second pressure receiving portions (36a, 36b) are integrally formed on the inner surface of the front end wall (12c). Two pressurizing portions (35a, 35b) are integrally formed on the front end surface of the slide piece (27) while being arranged in a V shape so that the pressure receiving projection (36) is sandwiched between them. The pressurizing part (35a) replaces the first pressure receiving part (36a). Even when the second pressurizing part (35b) presses the second pressure receiving part (36b), the component force (F1) acting on the pressure receiving projection (36) is applied to the control outer surface (8b). ) Is pressed against the control inner surface (8a) so as to press the slide piece (27). The engine intake air amount control device according to claim 3,
The opening angle (θ) of the pressurizing surfaces (35a1, 35b1) arranged in a V shape of the first and second pressurizing parts (35a, 35b) is set to 90 ° or more. Intake amount control device. The engine intake air amount control device according to claim 3 or 4,
A first spring seat (31) is provided at the front end of the slide piece (27), and a second spring seat (32) opposite to the first spring seat (31) is provided at the rear end of the control valve (12). Between the first and second spring seats (31, 32), the control valve (12) is urged rearward with respect to the slide piece (27), and the first and second pressure members ( 35. An engine intake air amount control device, wherein a coil spring (33) for holding a facing position between the first and second pressure receiving portions (36a, 36b) is contracted.

Images