JP2019078180A - Torsion spring for intake control device - Google Patents

Abstract

To provide a torsion spring for an intake control device which enables a stopper of the intake control device to be formed with resin.SOLUTION: A torsion spring 6 for an intake control device includes: a first spring part 19 and a second spring part 21 which apply biasing force to a lever member; and a spring connection part which connects the first spring part 19 to the second spring part 21. The spring connection part includes a first contact part 24 which contacts with a stopper of a body of the intake control device when a throttle valve of the intake control device is driven in a closed direction relative to a default opening position. The first contact part 24 includes a first stress relaxation surface 25 having a surface shape which relaxes stress occurring in the stopper when the first contact part 24 contacts with the stopper.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a torsion spring for applying a biasing force in a closing direction or an opening direction to a throttle valve in an intake control device.

  2. Description of the Related Art Conventionally, an intake control device is known that includes a throttle valve provided in an intake passage, a lever member that rotates integrally with the throttle valve, and a drive mechanism that rotates the lever member to open and close the throttle valve. In such an intake control device, a torsion spring may be used to apply an urging force in a closing direction or an opening direction of closing the throttle valve to the lever member according to the opening and closing drive of the throttle valve (for example, patent documents 1).

  The torsion spring of the intake control device of Patent Document 1 includes a first spring portion and a second spring portion, and a hook portion connecting these. One end of the first spring portion is fixed to the main body of the intake control device. The first spring portion applies a biasing force in the closing direction to the lever member when the throttle valve is driven to the fully open position side from the default open position defined by the system stopping portion provided in the main body. .

  The second spring portion is oppositely wound to the first spring portion, and one end of the second spring portion is fixed to the lever member. The second spring member applies an urging force in the opening direction to the lever member when the throttle valve is driven to the fully closed position side with respect to the default open position. The hook portion connecting the other ends of the first and second spring portions abuts the above-mentioned stop portion when the throttle valve is positioned closer to the closing direction than the default open position.

  When the drive mechanism becomes inoperable, the throttle valve is positioned in the default open position by the biasing force of the first spring portion and the second spring portion. As a result, a certain amount of intake to the internal combustion engine having the intake control device is secured, and the internal combustion engine does not stop immediately, so the vehicle having the internal combustion engine can be retracted.

Japanese Patent Laid-Open No. 2002-256894

  However, according to the intake control device of Patent Document 1, since the hook portion repeatedly abuts on the system stop portion as the throttle valve is driven to open and close, the system stop portion needs to have sufficient strength to withstand this. For this reason, it is necessary to select a high strength material for securing strength and to reinforce the locking portion in order to form the system stop portion with resin as a part of the resin case, which reduces the cost of the intake control device. It is difficult to

  An object of the present invention is to provide a torsion spring for an intake control device, which enables the stopper as the system stop portion of the intake control device to be easily formed of resin. .

The torsion spring for an intake control device according to the first invention is
Provided in an intake control device including a throttle valve provided in an intake passage, a lever member integrally rotating with the throttle valve, and a drive mechanism rotating the lever member to open and close the throttle valve. A torsion spring which applies an urging force in a closing direction or an opening direction to which the throttle valve is closed to the lever member in accordance with the opening and closing drive of the throttle valve,
An urging force on the lever member in the closing direction when one end is fixed to the main body of the intake control device and the throttle valve is driven to the fully open position side from the default open position defined by the stopper provided on the main body A first spring portion for applying
In the reverse winding with the first spring portion, one end is fixed to the lever member, and when the throttle valve is driven closer to the fully closed position than the default open position, an urging force in the opening direction is applied to the lever member A second spring portion that
A spring connecting portion connecting the other ends of the first spring portion and the second spring portion;
The spring connector is
And a first contact portion that contacts the stopper when the throttle valve is driven in the closing direction more than the default open position,
The first contact portion includes a stress relieving surface having a surface shape for relieving a stress generated inside the stopper when contacting the stopper.

  According to the first aspect of the invention, even when the stopper of the main body of the intake control device is made of resin, the first contact portion of the spring connecting portion contacts the stopper via the stress relieving surface. Therefore, the function of the stopper can be maintained without damaging the stopper. Thus, the portion of the main body having the stopper can be made of resin without any trouble, and the cost reduction of the intake control device and the design freedom can be improved.

  In the intake control device according to a second aspect of the present invention, in the first aspect, the stress relieving surface has a peripheral portion formed of a curved surface having a relatively large average curvature and an average curvature more than the peripheral portion inside the peripheral portion. It is characterized by comprising a main contact portion formed by a small curved surface.

  According to the second aspect of the invention, the stress generated inside the stopper when the first contact portion of the spring connection portion abuts on the stopper, the curved surface having a large curvature of the peripheral portion in the stress relaxation surface of the first contact portion The curved surface with a small curvature of the contact portion can be reliably relieved.

An intake control device according to a third aspect of the present invention is the second aspect of the present invention.
The first spring portion, the second spring portion and the spring connecting portion are formed of a single steel wire rod,
The spring connection portion has a U-shaped shape in which both ends are connected to the first spring portion and the second spring portion,
The U-shaped shape is perpendicular to the direction in which the surface including the U-shape abuts against the first abutment portion and the stopper.
The stress relieving surface is formed by a crushing process in which a U-shaped portion of the spring connecting portion is pressed in a direction in which the first contact portion and the stopper abut.

  According to the third invention, it is possible to form the stress relieving surface constituted by the peripheral portion and the main contact portion just by performing the above-mentioned crushing process.

An intake control device according to a fourth aspect of the present invention is the control system according to any one of the first to third aspects of the present invention,
The spring connecting portion includes a second contact portion that contacts an opener arm fixed to the lever member when the throttle valve is driven in the opening direction more than the default open position,
The second contact portion has a stress relieving surface having a surface shape similar to that of the stress relieving surface of the first contact portion.

  According to the fourth invention, the stress when the second contact portion of the spring connecting member abuts on the opener arm of the lever member can be similarly relieved.

It is a perspective view showing the principal part of the intake control device which has a torsion spring concerning one embodiment of the present invention. It is a figure which shows a mode that the drive mechanism and torsion spring of the intake control apparatus of FIG. 1 are accommodated in the case. It is a perspective view which shows the torsion spring of the intake control system of FIG. FIG. 4A is a cross-sectional view showing how a torsion spring contacts a resin stopper, FIG. 4A shows a conventional torsion spring, and FIG. 4B shows a torsion spring according to an embodiment of the present invention; Shows a torsion spring according to a more preferred embodiment.

  Hereinafter, embodiments of the present invention will be described using the drawings. FIG. 1 shows the main part of an intake control device having a torsion spring according to an embodiment of the present invention. As shown in FIG. 1, the intake control device 1 includes a throttle valve 3 provided in an intake passage 2, a lever member 4 that rotates integrally with the throttle valve 3 via a valve shaft 3a, and a lever member 4 And a drive mechanism 5 for rotating the throttle valve 3 for opening and closing.

  The torsion spring 6 applies an urging force to the lever member 4 in the closing direction or the opening direction in which the throttle valve 3 is closed according to the opening and closing drive of the throttle valve 3. The main body of the intake control device 1 is composed of a metal body 7 provided with the intake passage 2 and a case 8 (see FIG. 2) for accommodating the lever member 4 and the torsion spring 6.

  The drive mechanism 5 includes an electric motor 9 and a gear mechanism 10 for transmitting the driving force to the lever member 4. In the present embodiment, the electric motor 9 is held by the case 8, and the gear mechanism 10 is accommodated in the case 8. In FIG. 1, the case 8 is not shown in order to easily show the relationship among the body 7, the lever member 4, the drive mechanism 5, the torsion spring 6 and the like.

  FIG. 2 shows how the gear mechanism 10 and the torsion spring 6 are accommodated in the case 8. In addition, in FIG. 2, the said state is shown in the state which removed the cover part of case 8. As shown in FIG.

  As shown in FIG. 2, the gear mechanism 10 includes a pinion gear 12 attached to the output shaft 11 of the electric motor 9, a large diameter gear 13 meshing with the pinion gear 12, a small diameter gear 14 fixed to the large diameter gear 13, and a lever The valve gear 15 fixed to the member 4 and engaged with the small diameter gear 14 is provided. Therefore, the driving force of the electric motor 9 is decelerated by the drive mechanism 5 and transmitted to the lever member 4.

  The case 8 is provided with a rotation restricting pin 16 which is screwed to the case 8 from the outside and protrudes inside the case 8. The rotation restricting pin 16 abuts on the abutting portion 17 of the lever member 4 to block the rotation of the lever member 4, thereby defining the fully closed position of the throttle valve 3.

  The torsion spring 6 has a first spring portion 19 whose one end 18 is fixed to the case 8 constituting the main body, and the first spring portion 19 and a second spring portion 21 whose one end 20 is fixed to the lever member 4. And a spring connecting portion 22 connecting the other ends of the first spring portion 19 and the second spring portion 21. The 1st spring part 19, the 2nd spring part 21, and spring connection part 22 are formed by one steel wire rod.

  The first spring portion 19 applies an urging force to the lever member 4 in the closing direction when the throttle valve 3 is driven to the fully open position side from the default open position defined by the stopper 23 provided on the case 8 constituting the main body. Grant The second spring portion 21 applies an urging force in the opening direction to the lever member 4 when the throttle valve 3 is driven to the fully closed position side from the default open position.

  The default open position is a rotational position that the throttle valve 3 should take when the electric motor 9 becomes uncontrollable. When the throttle valve 3 is positioned at the default open position, a certain amount of intake air corresponding to the opening degree is supplied to the internal combustion engine having the intake control device 1. As a result, in the vehicle equipped with the internal combustion engine, even when the electric motor 9 becomes uncontrollable, a gentle drive is ensured, and measures such as evacuation can be taken.

  As shown in FIG. 3, the spring coupling portion 22 includes a first abutment portion 24 that abuts the stopper 23 when the throttle valve 3 is driven in the closing direction more than the default open position. The first contact portion 24 includes a first stress relieving surface 25 having a surface shape that relieves stress generated inside the stopper 23 when contacting the stopper 23.

  The spring connecting portion 22 has a U-shaped shape in which both ends are connected to the first spring portion 19 and the second spring portion 21. The U-shaped shape is perpendicular to the direction in which the surface including the U-shape abuts the first contact portion 24 and the stopper 23.

  FIGS. 4B and 4C show that the first contact portion 24 of the torsion spring 6 contacts the resin stopper 23 in a cross section perpendicular to the length direction of a portion of the steel wire rod that constitutes the first contact portion 24. Indicated. The first contact portion 24 has a planar first stress relieving surface 25a as the first stress relieving surface 25 as shown in FIG. 4B or a curved first stress relieving surface as shown in FIG. 4C. It has 25b.

  In the case of having the curved first stress relieving surface 25b, as described later, the stress generated inside the stopper 23 can be relieved more reliably, so it is preferable to the case of having the planar first stress relieving surface 25a. .

  The curved first stress relieving surface 25b has a peripheral contact portion 26 formed of a curved surface having a relatively large average curvature and a main contact formed of a curved surface having an average curvature smaller than that of the inner peripheral portion 26 of the peripheral portion 26. And a unit 27. Such a first stress relieving surface 25 b is crushed so as to press the first contact portion 24 having the U-shaped shape of the spring connection portion 22 in the direction in which the first contact portion 24 and the stopper 23 contact. It can be easily formed just by doing.

  That is, at the time of pressing for crushing, the metal of the steel wire rod forming the first contact portion 24 flows, and a curved surface having a large curvature of the peripheral portion 26 is formed. After that, when the pressure of the press is released, the elastic repulsive force of the steel wire which has been elastically deformed in the pressure direction is released, and the deformation is recovered, whereby a curved surface with a small curvature of the main contact portion 27 is formed. Be done.

  Further, the spring connecting portion 22 includes a second contact portion 29 that contacts the opener arm 28 fixed to the lever member 4 when the throttle valve 3 is driven in the opening direction more than the default opening position. The second contact portion 29 has a second stress relieving surface 30 having the same surface shape as the first stress relieving surface 25 of the first contact portion 24.

  The second stress relieving surface 30 may be planar as in the case of the first stress relieving surface 25a, but like the first stress relieving surface 25b, the peripheral portion 26 and the main contact portion It is preferable to have 27 and for the same reason.

  When the first contact portion 24 and the second contact portion 29 are continuous and the second stress relieving surface 30 is formed to be similar to the first stress relieving surface 25 b, the second stress relieving surface 30 and the second stress relieving surface 30 may be The stress relaxation surface 25b can be formed simultaneously. That is, the direction in which the second contact portion 29 and the opener arm 28 simultaneously contact the first contact portion 24 and the second contact portion 29 (the direction in which the first contact portion 24 and the stopper 23 contact) The crushing process to press to) may be performed.

  In FIGS. 1 and 2, the throttle valve 3 is in the fully closed position, the spring connecting portion 22 abuts against the stopper 23 (see FIG. 2) of the case 8, and the abutting portion 17 of the lever member 4 is rotated. It is in contact with the restriction pin 16.

  In this state, the second spring portion 21 is twisted by the stopper 23 and the lever member 4 to apply an urging force in the opening direction of the throttle valve 3 to the lever member 4. The first spring portion 19 is sandwiched between the case 8 and the stopper 23 and does not apply any force to the lever member 4.

  That is, in FIG. 1 and FIG. 2, the throttle valve 3 is moved from the default open position to the fully closed position against the biasing force of the second spring portion 21 by the electric motor 9 via the gear mechanism 10 and the lever member 4. The rotated state is shown.

  When the throttle valve 3 is rotated from this state to a predetermined position on the fully open position side of the default open position, the electric motor 9 is controlled to realize the rotation. That is, first, due to the biasing force of the second spring portion 21 and the control of the electric motor 9, the abutting portion 17 of the lever member 4 is separated from the rotation restricting pin 16 and the lever member 4 is rotated in the opening direction.

  As this rotation progresses, the opener arm 28 of the lever member 4 abuts on the second contact portion 29 of the spring connection portion 22. At this time, the stress generated inside the opener arm 28 by this contact is relieved by the second stress relieving surface 30 of the second contact portion 29. Further, the biasing force of the second spring portion 21 with respect to the lever member 4 does not work due to the contact.

  Further, when the lever member 4 is rotated in the opening direction by the electric motor 9, the opener arm 28 of the lever member 4 pushes the spring connection portion 22 in the rotation direction, so the first contact portion 24 of the spring connection portion 22 is a stopper Leave 23 At the same time, the biasing force in the closing direction is exerted on the lever member 4 by the first spring portion 19 via the opener arm 28.

  By further rotating the electric motor 9 against the biasing force, the throttle valve 3 can be rotated to a predetermined position on the fully open position side of the default open position.

  Conversely, when the throttle valve 3 is rotated from the predetermined position to the predetermined position on the fully closed position side of the default open position, the lever member 4 is driven by the driving force of the electric motor 9 and the biasing force of the first spring portion 19. The electric motor 9 is controlled to rotate in the closing direction. That is, the lever member 4 is closed based on the force with which the second contact portion 29 of the spring connecting portion 22 pushes the opener arm 28 of the lever member 4 and the driving force from the electric motor 9 transmitted to the lever member 4. To rotate.

  As this rotation progresses, the first contact portion 24 of the spring connection portion 22 abuts on the stopper 23. At this time, the stress generated inside the stopper 23 by this contact is relieved by the first stress relieving surface 25 of the first contact portion 24. Further, the biasing force of the first spring portion 19 is not applied to the lever member 4 due to the contact.

  When the electric motor 9 further rotates the lever member 4, the opener arm 28 of the lever member 4 separates from the spring connection portion 22 and the biasing force of the second spring portion 21 acts on the lever member 4. . By further rotating the electric motor 9 against the biasing force, the throttle valve 3 can be positioned at a predetermined position closer to the fully closed position than the default open position.

  During this time, when the electric motor 9 becomes uncontrollable when the throttle valve 3 is positioned closer to the fully closed position side than the default open position, the lever member 4 is rotated in the closing direction by the biasing force of the first spring portion 19. Do. Then, when the first contact portion 24 of the spring connection portion 22 abuts on the stopper 23, the biasing force is not loaded on the lever member 4, so that the throttle valve 3 is positioned at the default open position.

  On the other hand, when the electric motor 9 becomes uncontrollable when the throttle valve 3 is positioned closer to the fully closed position than the default open position, the lever member 4 is rotated in the opening direction by the biasing force of the second spring portion 21. Do. Then, when the opener arm 28 of the lever member 4 abuts on the second contact portion 29 of the spring connection portion 22, the biasing force is not loaded on the lever member 4 and the throttle valve 3 is positioned at the default open position.

  Therefore, even when the throttle valve 3 is at any open / close position, the throttle valve 3 is positioned at the default open position when the electric motor 9 can not be controlled due to its failure or failure of the control device. As a result, even when the electric motor 9 becomes uncontrollable, the internal combustion engine having the intake control device 1 does not stop immediately, so that traveling of a level to retract the vehicle having the internal combustion engine is secured.

  As described above, according to the present embodiment, when the first contact portion 24 of the spring connection portion 22 contacts the stopper 23 of the case 8 of the main body, the contact is made via the first stress relieving surface 25. In this case, the stress generated inside the stopper 23 can be relieved.

  That is, when the torsion spring is a conventional one having no stress relieving surface, as shown in FIG. 4A, the first contact portion 24b of the spring connecting portion that contacts the stopper 23 has a cylindrical shape. For this reason, when the first contact portion 24b abuts on the stopper 23 made of resin, a bending stress M is generated inside the stopper 23 and a tensile stress T is generated along the surface opposite to the abutting side. .

  Therefore, when the generation of these stresses is repeated according to the opening and closing drive of the throttle valve 3, the stopper 23 may be damaged. Therefore, it is necessary to take measures such as forming the stopper with a high-strength resin or reducing the tensile stress T by increasing the thickness of the stopper, but from the point of view of layout and cost, it is difficult to take any measures. .

  In this respect, when the first stress relieving surface 25 is a planar first stress relieving surface 25 a, the bending stress M and the tensile stress T are relieved as shown in FIG. 4B. Therefore, even when the stopper 23 is formed of resin, the function of the stopper 23 can be maintained without damaging the stopper 23. As a result, the portion having the stopper 23 of the main body can be made of resin without any trouble, and the cost reduction of the intake control device and the improvement of the design freedom can be achieved.

  In this case, it corresponds to the first stress relieving surface 25a which receives the surface pressure due to contact with the first contact portion 24 and the outer portion of the first stress relieving surface 25a which does not receive the surface pressure. Shear stress S is likely to occur between the portions of the stoppers 23.

  In the case where the first stress relieving surface 25 is a curved first stress relieving surface 25 b having a peripheral portion 26 having a large average curvature and a main contact portion 27 having a small average curvature, as shown in FIG. 4C, The surface pressure received by the contact with the first contact portion 24 is smaller as the main contact portion 27 is closer to the peripheral portion 26. Therefore, each part of the stopper 23 corresponding to the part far from the peripheral edge 26 of the main contact portion 27 receiving the surface pressure and the part not receiving the surface pressure closer to the peripheral edge 26 of the main contact part 27 The shear force acting on is considerably smaller than the shear stress S in FIG. 4B above.

  Further, when the contact moment accompanied by the impact load or the resin on the contact surface of the stopper 23 creeps, the first contact portion 24 abuts on the stopper 23 so as to sink. At this time, even if the peripheral edge portion 26 abuts against the stopper 23 due to such contact, the peripheral edge portion 26 has a curved surface shape, so that the stress acting on the inside of the portion abutted against the peripheral edge portion 26 of the stopper 23 can be reduced. .

  Therefore, damage to the stopper 23 formed of resin can be prevented more reliably, and the function of the stopper 23 can be more reliably maintained.

  When the first stress relieving surface 25 is the first stress relieving surface 25 b having the peripheral edge portion 26 and the main abutment portion 27 as shown in FIG. 4C, the first abutment portion 24 and the stopper 23 The first stress relieving surface 25 b can be easily formed by crushing processing that is pressed in the contact direction.

  In addition, the second contact portion 29 of the spring connecting portion 22 has a second stress relieving surface 30 having a surface shape similar to that of the first stress relieving surface 25 of the first contact portion 24. The stress when the portion 29 abuts against the opener arm 28 of the lever member 4 can be relaxed as well. In this case, if the first contact portion 24 and the second contact portion 29 are continuous and the second stress relieving surface 30 is the same as the first stress relieving surface 25 b of FIG. The first stress relieving surface 25 and the second stress relieving surface 30 can be simultaneously formed by processing.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to this. For example, the electric motor 9 may be held by a metal body 7 instead of being held by a resin case 8.

  DESCRIPTION OF SYMBOLS 1 ... intake control apparatus, 2 ... intake passage, 3 ... throttle valve, 4 ... lever member, 5 ... drive mechanism, 6 ... torsion spring, 7 ... body, 8 ... case, 9 ... electric motor, 10 ... gear mechanism, 11 ... Output shaft, 12 ... Pinion gear, 13 ... Large diameter gear, 14 ... Small diameter gear, 15 ... Valve gear, 16 ... Rotation regulation pin, 17 ... Abutment part, 18 ... One end, 19 ... First spring part, 20 ... One end , 21: second spring portion, 22: spring connection portion, 23: stopper, 24: first contact portion, 25, 25a, 25b: first stress relieving surface, 26: peripheral portion, 27: main contact portion, 28: opener arm, 29: second contact portion, 30: second stress relieving surface.

Claims (4)

Provided in an intake control device including a throttle valve provided in an intake passage, a lever member integrally rotating with the throttle valve, and a drive mechanism rotating the lever member to open and close the throttle valve. A torsion spring which applies an urging force in a closing direction or an opening direction to which the throttle valve is closed to the lever member in accordance with the opening and closing drive of the throttle valve,
An urging force on the lever member in the closing direction when one end is fixed to the main body of the intake control device and the throttle valve is driven to the fully open position side from the default open position defined by the stopper provided on the main body A first spring portion for applying
In the reverse winding with the first spring portion, one end is fixed to the lever member, and when the throttle valve is driven closer to the fully closed position than the default open position, an urging force in the opening direction is applied to the lever member A second spring portion that
A spring connecting portion connecting the other ends of the first spring portion and the second spring portion;
The spring connector is
And a first contact portion that contacts the stopper when the throttle valve is driven in the closing direction more than the default open position,
A torsion spring for an intake control device, wherein the first contact portion includes a stress relieving surface having a surface shape for relieving a stress generated inside the stopper when contacting the stopper.   The stress relieving surface includes a peripheral portion formed of a curved surface having a relatively large average curvature, and a main contact portion formed of a curved surface having an average curvature smaller than the peripheral portion on the inner side of the peripheral portion. The torsion spring for an intake control device according to claim 1, characterized in that: The first spring portion, the second spring portion and the spring connecting portion are formed of a single steel wire rod,
The spring connection portion has a U-shaped shape in which both ends are connected to the first spring portion and the second spring portion,
The U-shaped shape is perpendicular to the direction in which the surface including the U-shape abuts against the first abutment portion and the stopper.
The stress relieving surface is formed by a crushing process in which a U-shaped portion of the spring connecting portion is pressed in a direction in which the first contact portion and the stopper abut. The torsion spring for an intake control device according to Item 2. The spring connecting portion includes a second contact portion that contacts an opener arm fixed to the lever member when the throttle valve is driven in the opening direction more than the default open position,
The intake control according to any one of claims 1 to 3, wherein the second contact portion has a stress relieving surface having a surface shape similar to the stress relieving surface of the first contact portion. Device torsion spring.