JP2002188467A - Fitting structure of negative pressure actuator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To firmly fit a negative pressure actuator 2 to a duct 1, without using auxiliary small screws or the like. SOLUTION: The duct 1 made of a synthetic resin has a flat fitting seat 31, on which nearly rectangular opening 32 is formed. The negative pressure actuator 2 has a synthetic resin-made case 11, on the lower face of which a neck part 42 being projectingly formed and a locking piece 43 also is formed. A locking groove for tightly holding the peripheral edge of the opening 32 is formed between the locking piece 43 and the lower face of the case 11. The actuator 2 is fixed, by inserting the neck part 42 thereof into the opening 32 and then making it rotate by 90 degrees. Furthermore, a positioning recess 34 and a positioning projection 36 are formed at the duct 1 side of the fitting seat 31, and a circular arc-shaped projection 53 and a positioning hole 52 are formed at the actuator 2 side, respectively as the positioning parts for rotational direction. As a result of their engagement, the actuator 2 is prevented from loosening.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting structure of a negative pressure actuator which is mounted on a duct to constitute, for example, a switching valve or an on-off valve in an intake system of an internal combustion engine for an automobile.

[0002]

2. Description of the Related Art For example, an internal combustion engine for an automobile has two ducts for taking in outside air, and one of the ducts is provided with an on-off valve. In a low load range, a configuration is known in which intake air is taken in from only one duct by closing an on-off valve. In addition, there is also known a configuration of an intake system in which an intake flow path is switched according to intake air temperature.

As a switching valve or an on-off valve of an intake system in such an internal combustion engine for a vehicle, a structure using a negative pressure actuator is generally employed, and a negative pressure provided with a diaphragm in a substantially disk-shaped case. An actuator is mounted on the outer surface of the duct, and a plate-shaped valve element rotatably supported in the duct is driven by a valve operating rod of the negative pressure actuator.

The above-mentioned negative pressure actuator is usually fixed to the duct by using a plurality of screw members such as small screws, but in order to simplify the mounting work, the present applicant has previously described A mounting structure of a negative pressure actuator which can be fixed to a duct by inserting a neck portion of a bottom surface of a negative pressure actuator into an opening of a duct and sliding the same in a lateral direction has been proposed (Japanese Utility Model Laid-Open No. 6-47656). Gazette). That is, in this device, a substantially rectangular locking piece extending to both sides is formed at a neck slightly projecting 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 portion of the opening, the locking piece is engaged with the opening edge of the opening by sliding the locking piece toward the narrower opening, and the negative pressure actuator is moved. It is fixed.

[0005]

However, in the above-mentioned slide type mounting structure, although the operation itself of inserting and sliding the neck portion is simple, the vibration of the internal combustion engine and the running of the automobile can be performed as it is. Due to vibration or the like, there is a possibility that the film gradually returns in the sliding direction and falls off when a large vibration is applied. Therefore, in practice, it is necessary to fix the negative pressure actuator to the duct with small screws so that the negative pressure actuator does not move while being slid to the predetermined fixing position, and there is still room for improvement in this regard. there were.

[0006]

A negative pressure actuator mounting structure according to the present invention is characterized in that a valve operating rod is mounted on a diaphragm provided inside a synthetic resin case, and the valve is passed through a hole in the bottom surface of the case. A negative pressure actuator from which the operating rod protrudes, and a valve body associated with the valve operating rod is rotatably held, and
A synthetic resin duct having an opening through which the valve actuating rod has a flat mounting seat portion abutting on the bottom surface, and the mounting seat portion includes: An opening edge of the opening of the duct is sandwiched between a locking piece formed to extend laterally from the neck and the bottom surface, the neck having a projection protruding around the hole. A locking groove is formed, and the opening has a non-circular shape in which the locking piece can be inserted only at a predetermined angular position, and in the case and the duct,
A positioning portion that elastically engages with each other to perform positioning in the rotation direction is provided, and the negative pressure actuator is inserted into the opening of the duct and rotated by inserting the neck of the negative pressure actuator into the duct. It is characterized by being fixed.

It is desirable that the positioning portions are provided at two places 180 ° apart from the neck and the opening.

That is, in the present invention, the neck portion protrudes from the bottom surface of the case of the negative pressure actuator, a locking piece is formed, and a locking groove is formed between the locking piece and the bottom surface of the case. . And this neck together with the locking piece,
Insert it into the opening on the duct side. 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, if the case of the negative pressure actuator is rotated while keeping the bottom surface of the case in contact with the mounting seat on the duct side,
The locking groove and the opening edge of the opening are closely engaged with each other, and the negative pressure actuator is fixed to the duct while utilizing the 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, the positioning portion composed of a combination of concave portions and convex portions is elastically engaged, and the negative pressure actuator is reliably positioned in the rotational direction.

When the locking groove is engaged with the opening edge of the opening by sliding the negative pressure actuator as in the prior art described above, the vibration or the external force along the sliding direction causes the negative pressure actuator to slide. It is easy to move in the sliding direction, and as a result, it is easy to fall off.However, as in the present invention, in the configuration in which the locking groove is engaged with the opening edge of the opening by rotating in the rotating direction, for example, even if it receives Since there is no force to rotate the actuator,
It is essentially difficult to loosen. Moreover, the movement in the rotational direction is reliably prevented by the positioning portion. for that reason,
The vacuum actuator is secured to the duct without the need for other auxiliary means such as other machine screws.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings.

FIGS. 1 to 4 show an embodiment of the present invention in which a substantially disc-shaped negative pressure actuator 2 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 of an intake system of an internal combustion engine for a vehicle, and constitutes a pair of parallel intake passages together with another duct (not shown). By opening and closing the butterfly valve type valve element 3, the passage sectional area is changed in two stages.

The duct 1 is divided into an upper half 1A and a lower half 1B, each of which forms a semi-cylindrical shape.
The plurality of locking claws 4 provided along the side edge are integrally assembled with each other. One end in the longitudinal direction of the duct 1 is open in a trumpet shape as an outside air intake, and the other end is connected to a blow-molded subsequent duct (not shown) so as to have a large-diameter portion 7. It has become.
The valve element 3 housed inside the duct 1 has an elliptical shape, and both ends of a central rotating shaft 5 (see FIG. 3) are connected to the upper half 1.
It is rotatably held by a bearing 6 formed at the joint between A and the lower half 1B. The rotation of the valve body 3 does not interfere with the inner wall of the duct 1 so that the valve body 3
The swollen portions 8 and 9 which are substantially triangular when viewed from the side are formed in the upper half portion 1A and the lower half portion 1B over the rotation range of.

As shown in FIG. 9, the negative pressure actuator 2 has a hard synthetic resin case 11 composed of a body 12 and a cover 13, and a diaphragm 14 sandwiched between the body 12 and the cover 13. , The inside of which is partitioned into a negative pressure chamber 15 and an atmospheric pressure chamber 16,
A valve operating rod 19 is attached via retainers 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 a hole of the convex portion 21 on the upper surface of the valve body 3. In the negative pressure chamber 15, a return spring 22 is disposed in a compressed state.

The periphery of the valve body 3 is shown in FIGS.
, A seal member 23 is provided.

FIGS. 6 to 8 show the above-mentioned duct 1, especially the upper half 1A. As shown in these drawings, a substantially rectangular flat mounting seat 31 is formed on the upper surface of the duct 1, and an opening 32 is provided in the mounting seat 31. As is apparent from FIG. 7, the opening 32 has a substantially rectangular shape with the long side in the radial direction of the duct 1.
The duct 1 has a relatively narrow portion 32a along the longitudinal direction and a slightly enlarged portion 32b.
Also, the opening 32 as a whole has a duct 1 so that the narrow portion 32a is closer to the center of the mounting seat 31.
The opening is formed to be offset to one side of the opening.

Further, a portion serving as a positioning portion of the negative pressure actuator 2 is provided before and after the mounting seat portion 31, respectively. Specifically, in the vicinity of the trumpet-shaped opening,
Flange 33 extending along a plane perpendicular to the axis of duct 1
The outer edge of the flange 33 has a substantially trapezoidal shape, and a positioning recess 34 is formed on the top side thereof.
Are formed. Further, a cruciform boss 35 is protruded at a position opposite to the concave portion 34 with the mounting seat portion 31 interposed therebetween.
A positioning projection 36 is formed. The flange 33 and the cross-shaped boss 35 are formed integrally with the upper half 1A.

On the other hand, the negative pressure actuator 2
As shown in the figure, the lower surface 12a of the central portion of the body 12 has a flat surface, and the neck 42 projects so as to surround the center hole 41 through which the valve operating rod 19 passes. A pair of locking pieces 43 extending laterally are formed at the tip of 42. Thus, 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 periphery of the opening 32 of the mounting seat 31. FIG. 10 shows the details of the neck 42 and the locking piece 43. As shown in FIG.
The outer shape of the second and locking pieces 43 is substantially rectangular.
Each corner of the neck 42 is chamfered in an arc shape.

As shown in FIGS. 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. Is larger than the width L5 of the narrow portion 32a. The length L2 of the short side of the locking piece 43 is slightly smaller than the width L5. The length L3 of the long side of the neck 42 is substantially equal to the width L5.

As shown in FIGS. 9 and 5, the case 11 of the negative pressure actuator 2 has a substantially triangular tab 51 extending radially from a part of the outer peripheral edge. A positioning hole 52 is formed through. The positioning holes 52 are provided at positions corresponding to the positioning portion protrusions 36 in the cross-shaped boss 35 on the duct 1 side. An arc-shaped convex portion 53 slightly protruding in the radial direction is formed at a position 180 ° away from the tab 51. The arc-shaped 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 tabs 51 and arc-shaped convex portions 53 are formed integrally with the body 12 as shown in FIG.

The procedure for mounting the negative pressure actuator 2 is as follows. First, the negative pressure actuator 2 is set in a posture rotated by 90 ° from the state shown in FIG. Into the opening 32 on the side. At this time, as is clear from the dimensional relationship described above,
Since the opening 32 is larger than the locking piece 43, it can be inserted without any trouble. Then, with the lower surface 12a of the case 11 kept in contact with the mounting seat 31, the negative pressure actuator 2 is rotated by 90 ° until the posture shown in FIGS. As a result, the locking groove 44 of the neck 42 is in a state of tightly holding the periphery of the opening 32. At the same time, the arc-shaped convex portion 53 of the negative pressure actuator 2 fits into the positioning concave portion 34 on the duct 1 side, and the positioning hole 52 of the tab 51 engages with the positioning portion projection 36 of the cross-shaped boss 35. I do. The engagement of these parts is performed with slight elastic deformation of both the case 11 and the duct 1. Therefore, in the state where the parts are finally engaged at a predetermined position, the parts are firmly engaged without loosening. Also, the lower surface 12a of the case 11 is kept in close contact with the mounting seat 31. In particular, as can be understood from FIG. 3, the negative pressure actuator 2 has the center portion relatively pulled downward in FIG. Since the arc-shaped convex portion 53 and the tab 51 are relatively pushed upward by the flange 33 and the cross-shaped boss portion 35 on the duct 1 side, an appropriate elastic force always acts between them. No loosening occurs.

Therefore, the negative pressure actuator 2 can be mounted extremely simply and firmly without using an auxiliary fastener such as a small screw.

In the above-mentioned mounting operation, the arc-shaped convex portion 53 and the tab 51 of the negative pressure actuator 2 serve as clues for the rotation operation, and the workability is extremely good. this is,
The same is true not only for manual operation but also for automated assembly.

The duct 1 has an upper half 1A and a lower half 1B.
It is of course possible to attach the negative pressure actuator 2 after assembling, however, in the work of linking the valve body 3 and the valve operating rod 19, the negative pressure actuator 2 and the valve body 3 are first attached to the upper half 1A. After attaching the lower half 1B
It is desirable to assemble.

Further, since the negative pressure actuator 2 is attached to the duct 1 without using small screws or the like as described above, when discarding after elapse of the life, the negative pressure actuator 2 and the duct 1 can be easily and quickly separated. It is possible to separate the materials for recycling easily.

[0025]

As described above, according to the present invention, the negative pressure actuator can be mounted on the duct by merely rotating it, and in particular, an auxiliary fastening member such as a small screw is not required. It is very excellent in terms of points and work efficiency. Also, even if vibration or external force acts, there is almost no occurrence of a rotational moment for rotating the negative pressure actuator. Therefore, even if a small screw or the like is not used, there is no looseness over a long period of time. Mounting is possible.

In particular, if the positioning portions are provided at two places separated by 180 °, the positioning portion is reliably prevented from coming off due to slight inclination or deformation of the negative pressure actuator, and further reliability is improved. Can be increased.

[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 of the same.

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 sectional view of a negative pressure actuator.

FIG. 10 is a sectional view taken along the line AA of FIG. 9;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Duct 2 ... Negative pressure actuator 3 ... Valve 11 ... Case 31 ... Mounting seat 32 ... Opening 34 ... Positioning recess 36 ... Positioning projection 42 ... Neck 43 ... Locking piece 44 ... Locking groove 52 ... Positioning Hole 53: arc-shaped convex

Claims (2)

[Claims] 1. A negative pressure actuator having a valve operating rod attached to a diaphragm provided inside a synthetic resin case, the valve operating rod protruding through a hole in a bottom surface of the case, and being linked to the valve operating rod. A synthetic resin duct that has a flat mounting seat that abuts against the bottom surface and that has an opening through which the valve actuation rod passes. And having, on the bottom surface of the case, a neck protruding around the perimeter of the hole, between the locking piece formed to extend laterally from the neck and the bottom surface. A locking groove for holding the opening edge of the opening of the duct is formed, the opening forms a non-circular shape in which the locking piece can be inserted only at a predetermined angular position, and the casing has a non-circular shape. The duct and the duct are provided with a positioning portion that elastically engages with each other to perform positioning in the rotation direction, and the neck portion of the negative pressure actuator is inserted into the opening of the duct and rotated, thereby A mounting structure for a negative pressure actuator, wherein the negative pressure actuator is fixed to a duct. 2. The mounting structure for a negative pressure actuator according to claim 1, wherein said positioning portions are provided at two positions separated by 180 ° with respect to said neck portion and said opening portion.