JP4480883B2 - Mounting structure of negative pressure actuator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an attachment structure for a negative pressure actuator attached to a duct in order to constitute, for example, a switching valve or an on-off valve in an intake system of an automobile internal combustion engine.
[0002]
[Prior art]
For example, two internal air intake ducts for an internal combustion engine for automobiles are provided, and an open / close valve is provided on one of them. In the high speed and high load range, the open / close valve is opened and intake air is taken in from both ducts. A configuration is known in which intake air is taken in from only one duct by closing the on-off valve. In addition, an intake system configuration is also known in which the intake air flow path is switched in accordance with the intake air temperature.
[0003]
As such an intake system switching valve or on-off valve in such an internal combustion engine for automobiles, a configuration using a negative pressure actuator is generally employed, and a negative pressure actuator having a diaphragm in a substantially disc-shaped case is ducted. The valve operating rod of the negative pressure actuator is driven by a plate-like valve body that is attached to the outer surface of the plate and is rotatably supported in the duct.
[0004]
The negative pressure actuator is usually fixed to the duct using a plurality of screw members such as machine screws. However, in order to simplify the mounting operation, the applicant of the present invention has previously described a negative pressure actuator. A negative pressure actuator mounting structure has been proposed (see Japanese Utility Model Publication No. Hei 6-47656) in which the neck of the bottom surface of the pressure actuator is inserted into the opening of the duct and slid in the lateral direction to be fixed to the duct. That is, in this, a substantially rectangular locking piece extending to both sides is formed on the neck slightly protruding from the bottom surface of the negative pressure actuator, and the width of the opening on the duct side is different in two stages. After the locking piece is inserted from the wide width of the opening, the locking piece is engaged with the opening edge of the opening by sliding to the narrower width of the opening so that the negative pressure actuator It is supposed to be fixed.
[0005]
[Problems to be solved by the invention]
However, in the slide type mounting structure as described above, the operation of inserting and sliding the neck portion is simple, but as it is, the operation is gradually performed in the sliding direction due to the vibration of the internal combustion engine, the running vibration of the automobile, or the like. There is a risk of falling off when a large vibration is applied. Therefore, in actuality, it is necessary to fix the negative pressure actuator to the duct with a small screw so that the negative pressure actuator does not move in a state where the negative pressure actuator is slid to a predetermined fixing position. In this respect, there is still room for improvement. there were.
[0006]
[Means for Solving the Problems]
The negative pressure actuator mounting structure according to the present invention includes a negative pressure actuator in which a valve operating rod is attached to a diaphragm provided inside a synthetic resin case, and the valve operating rod protrudes through a hole in the bottom surface of the case. ,
The valve body linked to the valve operating rod is rotatably held, has a flat mounting seat that contacts the bottom surface, and the mounting seat includes an opening through which the valve operating rod passes. A synthetic resin duct,
With
The bottom of the case has a neck projecting so as to surround the periphery of the hole, and the opening of the duct is formed between a locking piece formed so as to extend laterally from the neck and the bottom. A locking groove for holding the opening edge is formed, the opening is non-circular so that the locking piece can be inserted only at a predetermined angular position, and the outer peripheral portion of the case and the duct are Positioning portions for positioning in the rotational direction by elastically engaging each other so as to relatively push up the case are provided, and the neck portion of the negative pressure actuator is inserted into the opening of the duct and rotated. Thus, the negative pressure actuator is fixed to the duct.
[0007]
Moreover, it is desirable that the positioning part is provided at two positions 180 degrees apart from each other with the neck part and the opening part as the center.
[0008]
That is, in the present invention, the neck portion protrudes from the bottom surface of the case of the negative pressure actuator, the locking piece is formed, and the locking groove is formed between the locking piece and the case bottom surface. And this neck part is inserted in the opening part by the side of a duct with a locking piece. At this time, if the posture of the negative pressure actuator is maintained at a predetermined angular position with respect to the duct, the locking piece is easily inserted into the opening. Then, after inserting the neck portion, if the case of the negative pressure actuator is rotated with the case bottom face in contact with the mounting seat portion on the duct side, the locking groove and the opening edge of the opening portion closely mesh with each other, The negative pressure actuator is fixed to the duct while utilizing slight elastic deformation of both the case and the duct made of synthetic resin. Further, when the negative pressure actuator is rotated to a predetermined position, a positioning portion composed of a combination of a concave portion and a convex portion is elastically engaged, and the negative pressure actuator is reliably positioned in the rotation direction.
[0009]
When the negative pressure actuator is slid and the locking groove is engaged with the opening edge of the opening as in the conventional case, the negative pressure actuator moves in the sliding direction when vibration or external force is applied along the sliding direction. As a result, the negative pressure actuator can be rotated even if it receives vibration, for example, in the configuration in which the locking groove is engaged with the opening edge of the opening as in the present invention. Since no force is generated, it is inherently difficult to loosen. Moreover, the movement in the rotational direction is reliably prevented by the positioning portion. For this reason, the negative pressure actuator is fixed to the duct without requiring an auxiliary means such as another machine screw.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.
[0011]
1 to 4 show an embodiment of the present invention in which a negative pressure actuator 2 having a substantially disc shape is attached to the outer surface of a duct 1 made of synthetic resin. The duct 1 is a portion serving as an outside air intake port of an intake system of an automobile internal combustion engine, and forms a pair of intake passages in parallel with another duct (not shown), depending on engine operating conditions. By opening and closing the butterfly valve type valve body 3, the passage cross-sectional area is changed in two stages.
[0012]
The duct 1 is formed by being divided into an upper half 1A and a lower half 1B each having a semi-cylindrical shape, and is integrally formed by a plurality of locking claws 4 provided along side edges. It is assembled. One end portion in the longitudinal direction of the duct 1 is opened in a trumpet shape as an outside air intake, and the other end portion is connected to a subsequent duct (not shown) which is blow-molded so as to be connected to the large diameter portion 7. It has become. The valve body 3 accommodated in the duct 1 has an oval shape, and both end portions of the central rotating shaft 5 (see FIG. 3) are formed at the joint between the upper half 1A and the lower half 1B. The bearing portion 6 is rotatably held. In order to prevent the inner wall of the duct 1 from interfering with the rotation of the valve body 3, the bulging portions 8 and 9 that form a substantially triangular shape when viewed from the side over the rotation range of the valve body 3. Are formed in the upper half 1A and the lower half 1B, respectively.
[0013]
As shown in FIG. 9, the negative pressure actuator 2 has a case 11 made of a hard synthetic resin made up of a body 12 and a cover 13, and the inside is surrounded by a diaphragm 14 sandwiched between the body 12 and the cover 13. While being divided into a negative pressure chamber 15 and an atmospheric pressure chamber 16, a valve operating rod 19 is attached via retainer plates 17 and 18 above and below the diaphragm 14. The cover 13 is integrally formed with a negative pressure inlet pipe 20 extending in the radial direction of the cover 13. The lower end of the valve operating rod 19 is formed in a substantially L shape as shown in FIG. 4, and this portion is engaged with the hole of the convex portion 21 on the upper surface of the valve body 3. A return spring 22 is disposed in the negative pressure chamber 15 in a compressed state.
[0014]
As shown in FIGS. 3 and 4, a seal member 23 is provided on the periphery of the valve body 3.
[0015]
6 to 8 show the above-described duct 1, particularly the upper half 1A. As shown in these drawings, a flat mounting seat 31 having a substantially rectangular shape is formed on the upper surface of the duct 1, and an opening 32 is provided in the mounting seat 31. As apparent from FIG. 7, the opening 32 has a substantially rectangular shape in which the radial direction of the duct 1 has a long side, and a portion 32 a having a relatively narrow width along the longitudinal direction of the duct 1 slightly. And an enlarged portion 32b. Further, the opening 32 as a whole is formed so as to be offset toward one side of the duct 1 so that the narrow portion 32 a is closer to the center of the mounting seat 31.
[0016]
In addition, before and after the mounting seat portion 31, portions serving as positioning portions for the negative pressure actuator 2 are provided. Specifically, a flange 33 extending along a surface perpendicular to the axis of the duct 1 is formed in the vicinity of the trumpet-shaped opening. The outer edge of the flange 33 forms a substantially trapezoidal shape, and the top of the flange 33 is formed. A positioning recess 34 is formed on the side. Further, a cruciform boss 35 is projected at a position opposite to the recess 34 across the mounting seat 31, and a positioning projection 36 is further formed at the center of the cruciform boss 35. Has been. Note that the flange 33 and the cross-shaped boss 35 are formed integrally with the upper half 1A.
[0017]
On the other hand, in the negative pressure actuator 2, as shown in FIG. 9, the lower surface 12a of the central portion of the body 12 forms a flat surface and surrounds the central hole 41 through which the valve operating rod 19 passes. The neck portion 42 protrudes, and a pair of locking pieces 43 extending laterally are formed at the tip of the neck portion 42. Thereby, a locking groove 44 is formed between the locking piece 43 and the lower surface 12a. The width of the gap of the locking groove 44 is set to be slightly smaller than the thickness of the peripheral edge of the opening 32 of the mounting seat portion 31. FIG. 10 shows the details of the neck portion 42 and the locking piece 43. As shown in the drawing, the neck portion 42 and the locking piece 43 have a substantially rectangular outer shape. It is chamfered in an arc shape.
[0018]
10 and 7, the length L1 of the long side of the locking piece 43 is slightly smaller than the length L4 of the long side of the opening 32, and the width of the opening 32 is the same. It is larger than the width L5 at the narrow portion 32a. Further, the length L2 of the short side of the locking piece 43 is slightly smaller than the width L5. And the length L3 of the long side of the neck part 42 is substantially equal to said width L5.
[0019]
Further, as shown in FIGS. 9 and 5, the case 11 of the negative pressure actuator 2 has a substantially triangular tab 51 extending in a radial direction from a part of the outer peripheral edge. A positioning hole 52 is formed in the tab 51. Is formed through. The positioning hole 52 is provided at a position corresponding to the positioning portion projection 36 in the cross-shaped boss portion 35 on the duct 1 side. In addition, an arcuate convex portion 53 that slightly protrudes in the radial direction is formed at a position 180 ° away from the tab 51. The arcuate convex portion 53 is provided at a position corresponding to the positioning portion concave portion 34 on the duct 1 side, and has an angle range corresponding to the size of the concave portion 34. These tab 51 and arcuate convex portion 53 are formed integrally with the body 12 as shown in FIG.
[0020]
As a procedure for mounting the negative pressure actuator 2, first, the negative pressure actuator 2 is rotated by 90 ° from the state shown in FIG. 5, and the neck 42 is opened on the duct 1 side at the relative angular position. Insert into part 32. At this time, as apparent from the dimensional relationship described above, the opening 32 is larger than the locking piece 43, so that it can be inserted without any trouble. Then, with the lower surface 12a of the case 11 in contact with the mounting seat 31, the negative pressure actuator 2 is rotated by 90 ° until the posture shown in FIGS. Thereby, the locking groove 44 of the neck part 42 will be in the state which clamped the periphery of the opening part 32 closely. At the same time, the arc-shaped convex portion 53 of the negative pressure actuator 2 fits into the positioning portion concave portion 34 on the duct 1 side, and the positioning hole 52 of the tab 51 engages with the positioning portion protrusion 36 of the cross-shaped boss portion 35. To do. Since these parts are engaged with a slight elastic deformation of both the case 11 and the duct 1, each part is in a state of being firmly engaged without loosening when finally engaged in a predetermined position. The lower surface 12 a of the case 11 is also kept in close contact with the mounting seat 31. In particular, as can be seen from FIG. 3, the negative pressure actuator 2 is pulled relatively downward in FIG. Since the arc-shaped convex portion 53 and the tab 51 are pushed upward relatively by the flange 33 and the cross-shaped boss portion 35 on the duct 1 side, an appropriate elastic force always acts between them. Does not cause looseness.
[0021]
Therefore, the negative pressure actuator 2 can be attached very simply and firmly without using an auxiliary fastener member such as a machine screw.
[0022]
Further, during the above-described mounting operation, the arcuate convex portion 53 and the tab 51 of the negative pressure actuator 2 serve as clues for the rotation operation, and workability is extremely good. This is not limited to the case of manual work, and the same applies to automated assembly.
[0023]
Of course, it is possible to attach the negative pressure actuator 2 after assembling the upper half 1A and the lower half 1B of the duct 1, but in the work of associating the valve body 3 and the valve operating rod 19, After attaching the negative pressure actuator 2 and the valve body 3 to the upper half 1A, it is desirable to assemble the lower half 1B.
[0024]
Further, since the negative pressure actuator 2 is attached to the duct 1 without using a small screw or the like as described above, the negative pressure actuator 2 and the duct 1 are easily and quickly disassembled when discarded after the end of the service life. And separation of materials for recycling is facilitated.
[0025]
【The invention's effect】
As described above, according to the present invention, the negative pressure actuator can be attached to the duct only by a rotational operation, and in particular, an auxiliary fastening member such as a machine screw is not necessary, so that the number of parts and work efficiency can be reduced. It will be very good on the top. In addition, even if vibration or external force is applied, there is almost no rotational moment to rotate the negative pressure actuator, so there is no looseness for long periods of time and reliability without using screws. Mounting is possible.
[0026]
In particular, if the positioning portions are provided at two positions separated by 180 °, it is possible to reliably avoid the positioning portion from being detached due to a slight inclination or deformation of the negative pressure actuator, thereby further improving the reliability. Can do.
[Brief description of the drawings]
FIG. 1 is a perspective view of an entire duct to which a negative pressure actuator according to an embodiment of the present invention is attached.
FIG. 2 is a top view of the same.
FIG. 3 is a longitudinal sectional view.
FIG. 4 is a front view of the same.
FIG. 5 is an exploded perspective view of a negative pressure actuator and a duct.
FIG. 6 is a perspective view of only the upper half of the duct.
FIG. 7 is a top view of the same.
FIG. 8 is a side view of the same.
FIG. 9 is a cross-sectional view of a negative pressure actuator.
10 is a cross-sectional view taken along line AA in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Duct 2 ... Negative pressure actuator 3 ... Valve body 11 ... Case 31 ... Mounting seat part 32 ... Opening part 34 ... Positioning recessed part 36 ... Positioning protrusion 42 ... Neck part 43 ... Locking piece 44 ... Locking groove 52 ... Positioning Hole 53 ... Arc-shaped convex part

Claims (2)

A negative pressure actuator in which a valve operating rod is attached to a diaphragm provided inside a synthetic resin case, and the valve operating rod protrudes through a hole in the bottom surface of the case;
The valve body linked to the valve operating rod is rotatably held, has a flat mounting seat that contacts the bottom surface, and the mounting seat includes an opening through which the valve operating rod passes. A synthetic resin duct,
With
The bottom of the case has a neck projecting so as to surround the periphery of the hole, and the opening of the duct is formed between a locking piece formed so as to extend laterally from the neck and the bottom. A locking groove for holding the opening edge is formed, the opening is non-circular so that the locking piece can be inserted only at a predetermined angular position, and the outer peripheral portion of the case and the duct are Positioning portions for positioning in the rotational direction by elastically engaging each other so as to relatively push up the case are provided, and the neck portion of the negative pressure actuator is inserted into the opening of the duct and rotated. The negative pressure actuator mounting structure, wherein the negative pressure actuator is fixed to a duct. 2. The mounting structure for a negative pressure actuator according to claim 1, wherein the positioning portions are provided at two positions 180 degrees apart from each other with the neck and the opening as the center.

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