JP6047030B2 - Electric actuator - Google Patents

Description

  The present invention relates to an electric actuator having a drive unit that is rotationally driven under an energization action.

  For example, in an internal combustion engine mounted on a vehicle or the like, intake air is diverted by an intake manifold having a plurality of branch pipes and supplied to each cylinder chamber. In recent years, when supplying air to each cylinder chamber, an intake manifold device that controls the flow direction of the air so as to form a spiral in the cylinder chamber has been used. In this intake manifold device, an actuator including a motor and a driving force transmission mechanism that transmits a driving force output by the motor to a rotation shaft is provided, and the actuator is housed in a housing, Mounted on the side.

  In such an actuator, for example, as disclosed in Patent Document 1, an end surface of a housing in which a motor is accommodated is closed by a cover member, and a gap is provided between the end surface and the cover member. The moisture that has entered the gap from the outside of the actuator can be discharged downward in the direction of gravity along the gap, and the housing communicates with the space in which the motor is accommodated and faces the gap described above. Thus, a breathing hole is formed to prevent the occurrence of condensation in the space.

JP 2010-229835 A

  However, in the above-described actuator, when the moisture that has entered the gap moves downward in the direction of gravity, when the moisture enters the recess that communicates with the breathing hole and the moisture that exceeds the volume in the recess accumulates, It will enter into the motor side through the breathing hole, resulting in malfunction of the motor.

  The present invention has been made in consideration of the above-described problems, and has an object to provide an electric actuator capable of reliably preventing moisture from entering the rotary drive source side with a simple configuration. To do.

In order to achieve the above object, the present invention provides an electric actuator comprising a housing that houses a rotational drive source, and a mounting surface that is formed on a side surface of the housing and is connected to another member via a gap. In
The housing is configured to have the said rotation drive source accommodated by housing portion and communicating hole which is open to the mounting surface side, a concave portion in the gravity direction lower side of the hole which is open to the mounting surface Yes, and the recess is characterized Rukoto provided on an outer peripheral wall surface of the housing portion.

According to the present invention, the housing that constitutes the electric actuator is formed such that the hole communicating with the housing portion in which the rotational drive source is housed opens to the mounting surface side, and the lower side in the gravity direction of the hole portion. Is provided with a recess opened on the mounting surface side, and the recess is provided on an outer peripheral wall surface of the storage portion.

Therefore, even when the electric actuator is submerged from the lower side in the direction of gravity, water can be stored in the concave portion provided below the hole, so that the water can be prevented from reaching the hole. It is possible to reliably prevent water from entering the rotation drive source through the hole. Moreover, while being able to increase the water storage amount in a recessed part, the said recessed part can be comprised using the lightening shape for weight reduction in a housing.

  In addition, the concave portion is provided between the storage portion and the mounting surface, and is formed so that the distance between the storage portion and the mounting surface increases toward the lower side in the direction of gravity, so that the gravity starts to be submerged. Since the volume on the lower side in the direction can be increased, the amount of water stored in the concave portion can be increased, and water can be reliably prevented from entering the rotary drive source through the hole.

  Furthermore, the other member faces the concave portion and is provided with another concave portion opened on the other mounting surface facing the mounting surface, so that the water stored in the other concave portion in addition to the concave portion can be stored. Can be further increased, and it is possible to more reliably prevent water from entering the storage unit in which the rotational drive source is stored.

  According to the present invention, the following effects can be obtained.

  That is, the housing that constitutes the electric actuator has a hole portion that communicates the storage portion in which the rotational drive source is stored and the mounting surface side, and is provided on the mounting surface side on the lower side in the gravity direction of the hole portion. By providing an open recess, even when the electric actuator is submerged from the lower side in the direction of gravity, water can be stored in the recess provided in the lower side of the hole in the direction of gravity. It is possible to reliably prevent water from entering the rotary drive source through the through hole.

1 is an external perspective view showing an intake manifold device to which an actuator according to an embodiment of the present invention is applied. It is sectional drawing along the II-II line of FIG. It is a disassembled perspective view of the housing and adapter which comprise the actuator of FIG.

  Preferred embodiments of the electric actuator according to the present invention will be described below and described in detail with reference to the accompanying drawings. In FIG. 1, reference numeral 10 indicates an electric actuator according to an embodiment of the present invention.

  As shown in FIG. 1, the electric actuator 10 is used in an intake manifold device 14 having a plurality of (for example, three) branch pipes 12, and the intake manifold device 14 includes a plurality of branch pipes 12. A manifold body 16 is provided, a valve 18 provided in each branch pipe 12, and a shaft 20 connected to each valve 18. Then, by rotating the shaft 20 by the electric actuator 10 provided at one end along the width direction of the manifold body 16, the flow rate and flow of air flowing through the branch pipe 12 by rotating the valve 18. The direction is controlled.

  As shown in FIGS. 1 to 3, the electric actuator 10 described above includes a housing 22 and a rotational drive source 24 housed in the housing 22, and the housing 22 is provided on the manifold body 16. It is connected to one end through an adapter (other member) 26.

  The housing 22 is made of, for example, a resin material, and includes a storage portion 28 that stores the rotational drive source 24, a mounting flange 30 that is formed in parallel with the axis of the storage portion 28, and a substantially center of the mounting flange 30. And a first annular protrusion 32 formed on the surface. The adapter 26 is attached to a first mounting surface 34 formed on one side surface of the housing 22 and including the mounting flange 30.

  The storage portion 28 is formed in a cylindrical shape with a circular cross section, for example, and the rotation drive source 24 is stored therein, and the storage portion 28 is closed by a cover 36 attached to one end portion along the axial direction. Is done. The outer peripheral side of the storage portion 28 is covered with an annular wall 38.

  The mounting flange 30 is formed on the other end side of the storage portion 28 and is formed substantially parallel to the axis of the storage portion 28, and a set of through holes 40 are formed at a predetermined interval. The through-hole 40 is formed so as to be orthogonal to the axis of the storage portion 28, and a cylindrical collar member 42 is press-fitted therein.

  As shown in FIGS. 2 and 3, the housing 22 is opened to the first mounting surface 34 side, and a first recess 44 is formed at a position on the outer peripheral side of the storage portion 28 with an annular wall 38 interposed therebetween. Is done. For example, when the electric actuator 10 is mounted on a vehicle, the first recess 44 is formed so as to gradually widen in a direction that is the lower side in the gravitational direction (arrow A direction). That is, the first recess 44 is formed in a triangular cross-section in which the depth with respect to the first mounting surface 34 gradually increases downward (in the direction of arrow A).

  Specifically, as shown in FIG. 2, the depth H2 on the lower end side is formed deeper than the depth H1 on the upper end side in the first recess 44 (H1 <H2).

  A breathing hole (hole) 46 that penetrates the annular wall 38 is formed between the first recess 44 and the storage portion 28, and the breathing hole 46 is substantially orthogonal to the first mounting surface 34. It is extended. Thereby, the storage part 28 and the 1st recessed part 44 will be in the state connected.

  Further, the breathing hole 46 is connected to the vicinity of the upper end portion which is the upper side in the gravity direction (arrow B direction) in the first recess 44. The breathing hole 46 is used for discharging the air in the storage portion 28 expanded by the heat generation to the outside when the rotational drive source 24 stored in the storage portion 28 generates heat during driving, It is provided for the purpose of keeping the external atmospheric pressure constant.

  Further, a hollow portion 48 that is recessed from the first mounting surface 34 to the annular wall 38 is formed on the housing 22 above the first recess 44 (in the direction of arrow B).

  The rotational drive source 24 is composed of, for example, a motor such as a stepping motor. The rotational drive source 24 is electrically connected to the connector 50 of the cover 36 in a state of being accommodated in the accommodating portion 28 of the housing 22, and is illustrated via a connection terminal (not shown) connected to the connector 50. The rotation drive source 24 is rotationally driven by receiving a control signal from the controller that does not.

  The driving force of the rotational drive source 24 is transmitted to the shaft 20 of the intake manifold device 14 via a driving force transmission mechanism (not shown), so that the plurality of valves 18 connected to the shaft 20 are connected to the branch pipes. 12 rotates. The shaft 20 is inserted through a first shaft hole 52 formed at the center of the first annular protrusion 32 in the housing 22.

  The adapter 26 is formed, for example, in a block shape having a predetermined thickness from a resin material, and is disposed such that the second mounting surface 54 serving as one end surface thereof faces the mounting flange 30 of the housing 22. It is fixed to the mounting flange 30 by 56. The other end surface of the adapter 26 is fixed to the manifold body 16 of the intake manifold device 14.

  The adapter 26 is formed with a second shaft hole 58 penetrating along the axial direction at a substantially central portion, and the second shaft hole 58 is in contact with the first annular protrusion 32 of the housing 22 on the outer peripheral side. Two annular protrusions 60 are formed. When the adapter 26 is assembled between the housing 22 and the manifold body 16, the shaft 20 is inserted into the second shaft hole 58. The adapter 26 may be formed integrally with the manifold body 16.

  Further, on the outer peripheral side of the second annular protrusion 60, a second recess (another recess) 62 that opens to the second mounting surface 54 side is formed, and the second recess 62 includes the adapter 26, the housing 22, and the second recess 62. Is formed at a position facing the first recess 44 when assembled. In addition, the 2nd recessed part 62 is formed so that the depth H3 (refer FIG. 2) with respect to the 2nd attachment surface 54 may become substantially constant.

  Further, on the outer peripheral side of the second annular protrusion 60, a set of mounting holes 64 is formed at a position corresponding to the through hole 40 of the mounting flange 30 in the housing 22 on the second mounting surface 54 side. Insert members 66 are press-fitted into the mounting holes 64, respectively.

  The insert member 66 is formed, for example, in a cylindrical shape from a metal material, and a screw hole 68 is formed in the center along the axial direction. The end of the insert member 66 is a second mounting surface of the adapter 26. 54 so as to protrude by a predetermined height with respect to 54.

  When the adapter 26 is assembled to the mounting flange 30 of the housing 22, as shown in FIG. 2, the first mounting surface 34 of the mounting flange 30 comes into contact with the end of the insert member 66, thereby A gap 70 with a predetermined interval is formed between the first mounting surface 34 and the second mounting surface 54 without contacting the second mounting surface 54. In this state, the fastening bolt 56 is inserted into the through hole 40 of the mounting flange 30 and screwed into the screw hole 68 of the insert member 66 in the adapter 26, so that a gap 70 is formed between the mounting flange 30 and the adapter 26. The housing 22 and the adapter 26 are connected in the formed state. In this case, the first and second recesses 44 and 62 are assembled so as to face each other and communicate with the gap 70.

  The gaps 70 are formed at regular intervals along the first mounting surface 34 of the housing 22 and the second mounting surface 54 of the adapter 26 (see FIG. 2).

  The intake manifold device 14 including the electric actuator 10 according to the embodiment of the present invention is basically configured as described above. Next, with respect to the electric actuator 10 from the lower side in the direction of gravity. The case where it is flooded will be described with reference to FIG.

  For example, when the vehicle travels on a flooded road or the like and is submerged from below the intake manifold device 14 including the electric actuator 10, the water moves upward along the gap 70 between the housing 22 and the adapter 26 (arrow B direction), since the first and second recesses 44 and 62 are provided in the gravity direction lower side (arrow A direction) with respect to the breathing hole 46, the first and second recesses 44, The breathing hole 46 is not reached until 62 is filled with the water. Therefore, even when the electric actuator 10 is submerged from the lower side in the direction of gravity, the water transmitted through the gap 70 can be collected by the first and second recesses 44 and 62, so Can be reliably prevented, and a short circuit of the rotational drive source 24 due to the flooding is prevented.

  Further, the first concave portion 44 is formed such that the lower side in the direction of gravity starting to enter through the gap 70 is widened with respect to the upper side, so that the water accumulated in the first concave portion 44 is reliably prevented from reaching the breathing hole 46. can do.

  The water accumulated in the first and second recesses 44 and 62 described above is discharged downward (in the direction of arrow A) through the gap 70 under the action of gravity after the flooded state is released.

  In the above-described embodiment, the electric actuator 10 and the intake manifold device 14 are assembled via the adapter 26, and the second recess 62 is formed so as to open to the second mounting surface 54 of the adapter 26. However, the present invention is not limited to this. For example, when the housing 22 is directly assembled to the intake manifold device 14 without using the adapter 26, the second recess is formed on the mounting surface of the manifold body 16. Should just be formed. That is, it is only necessary that the second recess is formed on the mounting surface of the mating member facing the first mounting surface 34 of the housing 22.

  As described above, in the present embodiment, the housing 22 constituting the electric actuator 10 has the breathing hole 46 that communicates the storage portion 28 in which the rotation drive source 24 is stored and the first mounting surface 34 side. A first recess 44 is formed between the breathing hole 46 and the first attachment surface 34 and is recessed from the first attachment surface 34 toward the storage portion 28. And since this 1st recessed part 44 is formed so that it may become deep gradually toward the gravity direction lower side (arrow A direction) at the time of mounting the electric actuator 10 in a vehicle etc., for example, the electric actuator 10 Even when the water is infiltrated from below, water can be stored in the first concave portion 44 provided on the lower side in the gravity direction than the breathing hole 46, and as a result, water enters the rotational drive source 24 through the breathing hole 46. It is possible to prevent the rotation drive source 24 from malfunctioning due to flooding.

  Further, since the first recess 44 is formed such that the distance between the storage portion 28 and the first mounting surface 34 increases toward the lower side in the gravitational direction (H1 <H2), the lower side in the gravitational direction at which the water starts to submerge. The volume of the water stored in the first concave portion 44 can be increased. Therefore, it is possible to reliably prevent water from entering the rotation drive source 24 (storage unit 28) through the breathing hole 46 from the first recess 44.

  Furthermore, by providing the first concave portion 44 on the outer peripheral side of the housing portion 28 in the housing 22, it is possible to increase the amount of water stored in the first concave portion 44, and to reduce the weight in the housing 22 for weight reduction. It can be used effectively.

  Furthermore, the adapter 26 connected to the housing 22 is formed with a second recess 62 opened in the second mounting surface 54 so as to face the first recess 44, so that a second in addition to the first recess 44 is provided. By storing the water soaked in the recesses 62, the amount of water stored can be further increased, and water can be more reliably prevented from entering the storage unit 28 through the breathing hole 46.

  Note that the electric actuator according to the present invention is not limited to the above-described embodiment, and various configurations can be adopted without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 10 ... Electric actuator 12 ... Branch pipe 14 ... Intake manifold apparatus 16 ... Manifold main body 18 ... Valve 20 ... Shaft 22 ... Housing 24 ... Rotation drive source 26 ... Adapter 28 ... Storage part 30 ... Mounting flange 34 ... 1st mounting surface 38 ... annular wall 40 ... through hole 44 ... first recess 46 ... breathing hole 54 ... second mounting surface 62 ... second recess 64 ... mounting hole 66 ... insert member 70 ... gap

Claims (3)

In an electric actuator comprising a housing in which a rotational drive source is housed, and a mounting surface formed on a side surface of the housing and connected to another member via a gap,
The housing is configured to have the said rotation drive source accommodated by housing portion and communicating hole which is open to the mounting surface side, a concave portion in the gravity direction lower side of the hole which is open to the mounting surface Yes, and the recess, electric actuator, characterized in Rukoto provided on an outer peripheral wall surface of the housing portion. The electric actuator according to claim 1, wherein
The concave portion is provided between the storage portion and the mounting surface, and is formed such that a distance between the storage portion and the mounting surface increases toward the lower side in the gravity direction. Electric actuator to do. The electric actuator according to claim 1 or 2 ,
The electric actuator according to claim 1, wherein the other member is provided with another recess facing the recess and opening in another mounting surface facing the mounting surface.

Images