Motor Actuator, Method of Processing Motor Actuator, and Method of Inspecting Motor Actuator

A motor actuator includes a housing that contains a motor, a sensor contained in the housing, and a transmission path capable of continuously transmitting a detection signal generated by the sensor. The housing has an insertion hole formed therein, and the insertion hole is capable of receiving a probe for taking out the detection signal from the transmission path. The detection signal of the sensor can be directly taken out from the transmission path through the probe. Accordingly, the detection signal of the sensor can be measured continuously with respect to a temporal change, and the accuracy in inspecting the output characteristics of the sensor can be increased.

CLAIM OF PRIORITY

This application claims priority to Japanese Patent Application No. JP2015-175636, filed on Sep. 7, 2015, of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to motor actuators for use in in-vehicle systems or the like, methods of processing motor actuators, and methods of inspecting motor actuators.

2. Description of the Related Art

A motor actuator (hereinafter, referred to as an actuator) is used as a driving source for a door of an air conditioning apparatus, a power window, or the like in an in-vehicle system. An actuator includes an electric motor, an output shaft rotationally driven by the electric motor, a rotation sensor for detecting the rotational position of the output shaft, and a control portion for controlling the electric motor (see Reference (1) in the following Related Art List). The control portion controls the electric motor in accordance with an operation instruction transmitted from an electronic control portion (ECU) so that the rotational position detection value output from the rotation sensor approaches a target value.

In this type of in-vehicle systems, a plurality of actuators are controlled integrally by the ECU. In such an in-vehicle system, serial communication, such as Local Interconnect Network (LIN), may be used in order to reduce the number of electric wires for connecting the plurality of actuators. In this serial communication, data is exchanged between the plurality of actuators and the ECU with the use of a single communication line.

After an actuator is assembled, the actuator may need to be inspected in order to check the output characteristics of the rotation sensor. This inspection is carried out, for example, by measuring the signal level of a detection signal that is output from the rotation sensor during the rotational position of the output shaft being changed. Therefore, when the output characteristics of the rotation sensor are inspected, a detection signal of the rotation sensor needs to be taken out from the actuator to the outside.

When a detection signal is to be taken out from the actuator having the aforementioned serial communication function, a conceivable technique is to output a detection signal through a communication line with the use of a communication protocol for the serial communication used by the actuator. However, with this type of communication protocol for the serial communication, a detection signal can be output from the actuator to the outside only in a case in which an operation instruction requesting for a current detection signal is transmitted to the actuator from an external control apparatus. Thus, only an intermittent detection signal with respect to a temporal change can be taken out from the actuator, and a continuous detection signal with respect to the temporal change cannot be taken out. Accordingly, when the inspection is carried out through the above-described technique, favorable detection accuracy may be hard to obtain.

SUMMARY OF THE INVENTION

The present invention has been made in view of such a problem, and one of purposes thereof is to provide a technique by which the inspection accuracy can be increased when inspecting output characteristics of a sensor inside a housing.

An aspect of the present invention for solving the above-described problem provides a motor actuator. The motor actuator includes a housing that contains a motor, a sensor contained in the housing, and a transmission path capable of continuously transmitting a detection signal generated by the sensor. The housing has an insertion hole formed therein, and the insertion hole is capable of receiving a probe for taking out the detection signal from the transmission path.

According to this aspect, the detection signal of the sensor can be directly taken out from the transmission path through the probe. Accordingly, the detection signal of the sensor can be measured continuously with respect to a temporal change, and the accuracy in inspecting the output characteristics of the sensor can be increased.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, in embodiments and modifications, identical constituent elements are given identical reference characters, and duplicate descriptions thereof will be omitted. In addition, in each of the drawings, constituent elements are partially omitted as appropriate for simplifying the description.

First Embodiment

FIG. 1is a configuration diagram illustrating an actuator10and an inspection apparatus200for use in an inspection method according to a first embodiment.

The overview of the inspection method will be described. In the inspection method, a probe202of the inspection apparatus200is inserted into a probe insertion hole14formed in a housing12of the actuator10. A transmission path capable of continuously transmitting a detection signal generated by a sensor is disposed inside the housing12, and the leading end portion of the probe202makes contact with a conductor constituting a portion of the transmission path. The detection signal of the sensor can be directly taken out from the probe202, and the detection signal of the sensor can be measured continuously by a measuring device210of the inspection apparatus200.

FIG. 2is a block diagram illustrating functionality of the actuator10and the inspection apparatus200.

As illustrated inFIGS. 1 and 2, the inspection apparatus200includes an external connector204, an external control device206, and a wiring harness208. The external connector204is detachably mounted to a connector portion12gformed on the housing12of the actuator10. The external control device206controls a control portion38(described later) of the actuator10from the outside. The wiring harness208connects the external control device206and the external connector204. The external control device206is constituted by a computer in which a central processing unit (CPU), a read-only memory (ROM), a random-access memory (RAM), and so on are combined. The wiring harness208includes a ground line208athat serves as a ground potential, a power-supply line208bfor supplying power from the external control device206, and a communication line208cthat constitutes a portion of a communication path for transmitting and receiving data to and from the external control device206.

The inspection apparatus200further includes the probe202for taking out a detection signal (described later) generated by a rotation sensor22(described later) of the actuator10, and the measuring device210for measuring the signal level of the detection signal output from the probe202. The measuring device210is a voltmeter that measures the voltage level of the detection signal output from the probe202. The measuring device210measures, as the voltage level, a potential difference of the detection signal relative to the ground potential.

The actuator10will now be described.

FIG. 3is a perspective view of the actuator10, andFIG. 4is an exploded perspective view of the actuator10. Although a characteristic feature of the actuator10lies in the probe insertion hole14of the housing12as described above, the peripheral structure will be described first.

The actuator10includes the housing12. The housing12is formed of a resin material. The housing12contains internal components, such as an electric motor16, the rotation sensor22, and a control circuit board26, which will be described later.

The housing12is constituted by an upper housing member12A (first housing member) and a lower housing member12B (second housing member). Each of the housing members12A and12B has a shape obtained by dividing the housing12in a height direction Z. The height direction Z corresponds to the axial direction of an output shaft20, which will be described later. The housing members12A and12B are detachably attached to each other through a snap-fit method or the like.

As illustrated inFIG. 3, the housing12includes four side surface portions12a,12b,12c,and12dthat are provided around the directional axis along the height direction Z and two side surface portions12eand12fthat are provided on two sides in the height direction Z. Among the plurality of side surface portions12a-12dof the housing12, the side surface portion12ais provided with the connector portion12gto which the external connector204(seeFIG. 1) can be mounted. The connector portion12ghas a cylindrical shape that projects toward the outside from the side surface portion12a.A connector insertion hole12his formed in the connector portion12g,and the external connector204can be inserted into the connector insertion hole12h.Hereinafter, with regard to the positional relationship of the housing12, the side where the connector portion12gis provided is set to be the front side. The side surface portion12aof the housing12is referred to as a front side surface portion12a,and the side surface portion12b,which is on the side opposite to the front side surface portion12a,is referred to as a back side surface portion12b.

As illustrated inFIG. 4, the actuator10further includes the electric motor16, a speed-reduction mechanism18, and the output shaft20. The speed-reduction mechanism18can transmit the rotary power output from a motor shaft (not illustrated) of the electric motor16while reducing the speed thereof. The output shaft20is rotationally driven by the rotary power transmitted from the speed-reduction mechanism18. The electric motor16is a DC motor. The speed-reduction mechanism18is a gear mechanism in which a screw gear and a spur gear are combined and includes an output gear18athat is a final-stage spur gear. The output shaft20is rotatably supported by a bearing portion (not illustrated) of the housing12and is provided so as to be rotatable along with the output gear18a.One end portion (an end portion on the lower side in the drawing) of the output shaft20projects from the housing12to the outside, and the rotary power is output from the one end portion to an apparatus to be driven. The apparatus to be driven is, for example, a door that opens or closes an airflow passage of an air conditioning apparatus.

FIG. 5is an exploded perspective view illustrating the rotation sensor22and the control circuit board26of the actuator10.

As illustrated inFIGS. 2 and 5, the actuator10further includes the rotation sensor22for detecting the rotational position of the output shaft20. The rotation sensor22includes a sensor circuit board22b(hereinafter, simply referred to as a sensor board22bas well) in which a conductive detection pattern22ais formed, and a brush22c(not illustrated inFIG. 5) that makes contact with the detection pattern22a.The rotation sensor22is disposed between the output gear18aand the base of the lower housing member12B. The sensor board22bis disposed in the housing12in a state in which the position thereof is retained, and the brush22cis provided so as to be rotatable along with the output shaft20and the output gear18a.The detection pattern22aand the brush22cconstitute a variable resistor (potentiometer).

Three sensor terminals24a-24care connected to the sensor board22b.The sensor terminals24a-24cinclude a ground sensor terminal24athat serves as a ground potential, a power-supply sensor terminal24bfor applying a sensor driving voltage to the detection pattern22a,and an output sensor terminal24cfor outputting a detection signal from the detection pattern22a.

When the output shaft20rotates while the sensor driving voltage is being applied to the power-supply sensor terminal24b,the position of the contact point between the brush22cand the detection pattern22achanges, and a voltage signal whose magnitude varies in accordance with the rotational position of the output shaft20is output from the output sensor terminal24c.This voltage signal constitutes a detection signal that indicates the rotational position of the output shaft20. In this manner, the rotation sensor22has a function of generating a detection signal that indicates the rotational position of the output shaft20and outputting the detection signal through the output sensor terminal24c.The rotation sensor22of this type is well known, and thus detailed description thereof will be omitted in the present specification.

As illustrated inFIGS. 2, 4, and 5, the actuator10further includes the control circuit board26(hereinafter, simply referred to as the control board26) for controlling the electric motor16. The control board26is disposed on an inner side of the front side surface portion12aof the housing12in a state in which the position of the control board26inside the housing12is retained.

Three connector terminal28a,28b,and28care connected to the control board26. The connector terminals28a-28cinclude a ground connector terminal28athat serves as a ground potential and a power-supply connector terminal28bfor supplying power from the external control device206. In addition, the connector terminals28a-28cinclude a communication connector terminal28cthat constitutes a portion of the communication path for transmitting and receiving data to and from the external control device206.

As illustrated inFIGS. 2 and 4, two relay terminals32aand32bare connected to the control board26. The relay terminals32aand32bare connected to a pair of motor terminals16aof the electric motor16. The relay terminals32aand32bare used to supply, to the electric motor16, a motor driving voltage for normally rotating or reversely rotating the electric motor16.

An IC chip34serving as a circuit element is mounted to the control board26. The IC chip34serves as a circuit element that constitutes a communication portion36for communicating with the external control device206and the control portion38for controlling the electric motor16and the rotation sensor22.

The communication portion36transmits and receives data to and from the external control device206through serial communication (multiplex communication) with the use of the single communication line208cin accordance with a predetermined communication protocol. In this communication protocol, a master-slave communication system is used. In this communication system, the external control device206is the master and the actuator10is the slave. Under this communication protocol, the control portion38of the actuator10operates in accordance with an operation instruction transmitted from the external control device206. This communication protocol is, for example, Local Interconnect Network (LIN) or Controller Area Network (CAN).

Upon being supplied with power from the external control device206, the control portion38generates a motor driving voltage and supplies the motor driving voltage to the electric motor16, and generates a sensor driving voltage and supplies the sensor driving voltage to the rotation sensor22.

In addition, the control portion38controls the electric motor16in accordance with a rotational operation instruction, transmitted from the external control device206, for rotating the electric motor16. Specifically, the control portion38controls the direction in which the electric motor16rotates and the number of rotations of the electric motor16so that the rotational position detection value indicated by the detection signal output from the rotation sensor22approaches the rotational position instruction value included in the rotational operation instruction transmitted from the external control device206.

The control portion38receives an analog-value detection signal from the rotation sensor22through a transmission path48(described later). The control portion38subjects the analog-value detection signal to predetermined processing including A/D conversion processing and acquires a digital-value detection signal. The control portion38carries out the control of the electric motor16and so on with the use of the digital-value detection signal.

FIG. 6is an outline drawing of the front surface side of the control board26.

As illustrated inFIGS. 2 and 6, a plurality of circuit elements34and44including the IC chip34are mounted on the front surface of the control board26. And a plurality of conductor patterns42and44for providing electrical continuity to the sensor terminals24a-24cand so on are formed on the front surface of the control board26.FIG. 6illustrates only the plurality of conductor patterns42and44for providing electrical continuity between the IC chip34and the sensor terminals24a-24cand relay terminals32aand32b.A through-hole electrode46is formed at one end portion of each of the conductor patterns42, and the terminals24a-24c,32a,and32bare inserted into the through-hole electrodes46and soldered (not illustrated) for electrical continuity.

The conductor patterns42and44include a transmission pattern44that constitutes a portion of the transmission path48capable of continuously transmitting a detection signal generated by the rotation sensor22. The transmission path48is constituted by the output sensor terminal24cof the rotation sensor22and the transmission pattern44, and an analog-value detection signal generated by the rotation sensor22is transmitted to the transmission path48. The transmission pattern44provides electrical continuity between the output sensor terminal24cof the rotation sensor22and the IC chip34.

The transmission pattern44includes a primary transmission pattern44athat constitutes a portion of a primary transmission path for transmitting a detection signal from the rotation sensor22(from the through-hole electrode46inFIG. 6) to the IC chip34, and an auxiliary transmission pattern44bthat constitutes an auxiliary transmission path formed by a portion that has branched off from the primary transmission pattern44a.Assuming a side of the position at which the auxiliary transmission pattern44bbranches off from the primary transmission pattern44ais seen as a base end side, the auxiliary transmission pattern44bis formed such that the leading end side thereof is a dead end.

A linear portion44bahaving a substantially constant pattern width and a probe abutting portion44bbat the leading end portion of the auxiliary transmission pattern44bare formed in the auxiliary transmission pattern44b.The probe abutting portion44bbis provided to facilitate abutting of the leading end portion of the probe202and is formed to have a greater width than the linear portion44ba, which is the other portion adjacent to the probe abutting portion44bbin the auxiliary transmission path. In the present embodiment, the probe abutting portion44bbis formed in a circular shape. In this manner, the auxiliary transmission pattern44bis used to allow the probe202to make contact therewith.

The probe insertion hole14will now be described.FIG. 7is a sectional view illustrating the probe insertion hole14in the actuator10.

As illustrated inFIGS. 3 and 7, the probe insertion hole14is formed, among the plurality of side surface portions12a-12fof the housing12, in the front side surface portion12aon which the connector portion12gis formed. The probe insertion hole14is formed on the front side surface portion12aof the housing12at a position that is different from the position where the connector portion12gis formed. The probe202to be used for the inspection of the actuator10can be inserted into the probe insertion hole14in the direction Pa. The probe202is for continuously taking out the detection signal of the rotation sensor22from the probe abutting portion44bbof the auxiliary transmission pattern44bthat constitutes a portion of the transmission path48to which the detection signal is continuously transmitted.

On the front side surface portion12aof the housing12, a convex portion14bis formed at a peripheral portion14aof the probe insertion hole14. The convex portion14bis formed in a cylindrical shape that projects from the housing12toward the outside, and the inner side of the convex portion14bforms a portion of the probe insertion hole14. On the front side surface portion12aof the housing12, a concave portion14cis formed around the root portion of the convex portion14bthat is on the side opposite to the direction in which the convex portion14bprojects. The concave portion14cis dented in the direction opposite to the direction in which the convex portion14bprojects. The concave portion14cis formed in a continuous annular groove shape that surrounds the root portion of the cylindrical convex portion14b.The effects of the convex portion14band the concave portion14cwill be described later.

The probe abutting portion44bbon the control board26described above is disposed at a position that is inside the housing12and that is disposed on a straight line La passing through the center axis of the probe insertion hole14so as to facilitate abutting of the probe202. In other words, the probe abutting portion44bbis disposed on the inner side of the housing12relative to the probe insertion hole14. When viewed from another perspective, the probe abutting portion44bb, which constitutes a portion of the transmission path48, is disposed at a position at which the leading end portion of the probe202inserted in the probe insertion hole14can abut.

FIG. 8illustrates the shape of the probe abutting portion44bb, as viewed from one side (right side inFIG. 7) in the axial direction of the probe insertion hole14.

The probe abutting portion44bbis shaped such that, as viewed from one side in the axial direction of the probe insertion hole14, an outline14dof a cross-sectional shape of the probe insertion hole14orthogonal to the axial direction is fit inside an outline44cof a surface shape of the probe abutting portion44bb. This configuration makes it easier to dispose the probe abutting portion44bbon the straight line La passing through the center axis of the probe insertion hole14even when an error, such as a dimension error or an assembly error, of the housing12or the like is present, and the probe202can be made to stably abut against the probe abutting portion44bbwith ease.

Now, an inspection method in which the above-described actuator10is used will be described.

This inspection is carried out for an assembled actuator10. The assembled actuator10″ as used herein refers to an actuator10obtained by containing the internal components, such as the electric motor16, in the lower housing member12B and then attaching the upper housing member12A to the lower housing member12B as illustrated inFIG. 3.

As illustrated inFIGS. 1 and 2, in the inspection method, an operator first inserts the external connector204of the inspection apparatus200into the connector portion12gof the housing12. Thus, the external control device206and the control portion38of the actuator10become electrically connected. This operation is for supplying power from the external control device206to the electric motor16and the rotation sensor22through the control portion38and for transmitting an operation instruction from the external control device206to the control portion38.

The operator inserts the probe202into the probe insertion hole14of the housing12and brings the leading end portion of the probe202into contact with the probe abutting portion44bbon the control board26. Thus, the probe abutting portion44bbof the actuator10and the probe202become having electrically continuity, and the probe abutting portion44bband the measuring device210become electrically connected through the probe202.

The operator operates the external control device206to supply power from the external control device206to the electric motor16and the rotation sensor22through the control board26. In addition, the operator operates the external control device206to transmit a rotational operation instruction for rotating the electric motor16from the external control device206. Thus, the control portion38of the actuator10causes the electric motor16to operate in accordance with the rotational operation instruction so as to rotationally drive the output shaft20.

While the output shaft20rotates, a detection signal generated by the rotation sensor22is continuously transmitted to the transmission path48including the auxiliary transmission pattern44b.The detection signal continuously transmitted to the auxiliary transmission pattern44bis continuously taken out to the measuring device210through the probe202from the probe abutting portion44bb. Thus, the signal level of the detection signal can be measured continuously by the measuring device210. The operator checks a temporal change in the signal level of the detection signal, and thus the output characteristics of the rotation sensor22can be inspected. At this time, the probe202takes out an analog-value detection signal generated by the rotation sensor22, and the output characteristics of the rotation sensor22are inspected with the use of the analog-value detection signal. The measuring device210is provided with a display portion (not illustrated), such as gradations or the like, that displays the measurement result, and the operator can check the signal level of the detection signal through the content displayed on the display portion.

The effects of the actuator10and the inspection method described above will be described.

FIG. 9is a graph illustrating a relationship between the rotational position of the output shaft20and the signal level of the detection signal of the rotation sensor22. The solid line L1indicated inFIG. 9represents the measurement value obtained when the detection signal of the rotation sensor22is measured continuously. The points P1indicated inFIG. 9represent the measurement values obtained when the detection signal of the rotation sensor22is measured intermittently. In addition, the two dashed lines L2indicated inFIG. 9represent the reference lines for determining the quality of the output characteristics of the rotation sensor22. The assumption for the point data indicated inFIG. 9is that, after a rotational operation instruction is transmitted from the external control device206, an operation instruction requesting for a current detection signal is transmitted from the external control device206at a constant interval. Thus, the external control device206can acquire the detection signal of the rotation sensor22through the communication line208c,and the detection signal is measured intermittently.

(A) In the actuator10according to the present embodiment, the probe insertion hole14that can have the probe202inserted thereinto is formed in the housing12. Thus, the detection signal of the rotation sensor22can be directly taken out from the transmission path48through the probe202. Accordingly, the detection signal of the rotation sensor22can be measured continuously with respect to a temporal change, and the accuracy in inspecting the output characteristics of the rotation sensor22can be increased, as compared to a case in which the detection signal is measured intermittently with respect to a temporal change, as illustrated inFIG. 9.

(B) Consider a case in which the detection signal is taken out by transmitting an operation instruction requesting for a current detection signal from the external control device to the control portion38of the actuator10, as described above. In this case, a method can be contemplated in which the number of measurement points is increased by increasing the number of transmitting the operation instruction in order to improve the inspecting accuracy of the output characteristics of the rotation sensor22. However, in this case, increasing the number of transmitting the operation instruction causes increasing the number of processes required for the instruction operation, and an extended period of time is required for the inspection operation. In this respect, with the actuator10according to the present embodiment, the detection signal of the rotation sensor22can be measured continuously. Accordingly, the number of processes and the time required for the inspection operation can be reduced by reducing the number of transmitting the operation instruction from the external control device206, and the accuracy for inspecting the output characteristics of the rotation sensor22can be improved.

In addition, the probe insertion hole14is formed in the housing12at a position different from the position where the connector portion12gis formed. Thus, even if the probe insertion hole14is plugged up after the inspection operation is finished as described later, the external connector204can be detachably mounted to the connector portion12g.

(C) The probe abutting portion44bbis formed in the conductor pattern44that constitutes a portion of the transmission path48, which makes it easier to have the leading end portion of the probe202inserted in the probe insertion hole14abut against the conductor pattern44. Accordingly, an operation of bringing the probe202into contact with the conductor pattern44is facilitated, and the operability of the inspection operation improves.

(D) The probe abutting portion44bbis formed in the conductor pattern44on the control circuit board26, and thus a broader area can easily be secured for the probe abutting portion44bbthan in a case in which the probe abutting portion44bbis formed in a terminal, such as the output sensor terminal24c,that constitutes a portion of the transmission path48. Accordingly, an operation of bringing the probe202into contact with the probe abutting portion44bbis facilitated, and the operability of the inspection operation improves.

(E) The transmission path48includes, in addition to the primary transmission pattern44a,the auxiliary transmission pattern44binto which the probe202is brought into contact. Accordingly, the primary transmission pattern44adoes not need to make contact with the probe202, and the inspection operation can be carried out by using the auxiliary transmission pattern44bwhile the primary transmission pattern44ais being protected from making contact with the probe202.

In addition, consider a modification in which the probe insertion hole14is formed in the right side surface portion12c(seeFIG. 1), instead of the front side surface portion12a,of the housing12. In this case, when the external connector204is inserted into the connector portion12gof the housing12, the housing12should be held from the back side surface portion12b,which is opposite to the front side surface portion12a,of the housing12in order to prevent the actuator10from moving. In addition, when the probe202is inserted into the probe insertion hole14in the housing12, the housing12should be held from the left side surface portion12d(seeFIG. 3), which is opposite to the right side surface portion12c,of the housing12in order to prevent the actuator10from moving. In this manner, with the modification, the position that should be held varies between the time when the external connector204is inserted and the time when the probe202is inserted.

In contrast, according to the present embodiment, the connector portion12gand the probe insertion hole14are formed in the front side surface portion12aof the housing12. Accordingly, when the external connector204and the probe202are inserted into the connector portion12gand the probe insertion hole14, respectively, the operation can be carried out while the housing12is held from the same position (the back side surface portion12bof the housing12), and the operability of the inspection operation improves.

A method of processing the above-described actuator10will now be described.

If the probe insertion hole14of the actuator10is left open after the inspection operation described above finishes, a foreign object, such as dust, may enter the housing12through the probe insertion hole14and affect the operation of the internal components in the housing12.

Therefore, in the processing method, as illustrated inFIG. 10A, the process of heating and melting the peripheral portion14aof the probe insertion hole14of the housing12which constitutes a portion of the housing12, and plugging up the probe insertion hole14with a molten resin is carried out. This process is carried out with the use of a heating device212, such as a heated iron. The operator heats and melts a portion of the housing12by using the heating device212and guides the resulting molten resin to flow into the probe insertion hole14. With this operation, a plugging body50that plugs up the probe insertion hole14is formed in the housing12, as illustrated inFIG. 10B. The plugging body50is formed integrally with the peripheral portion14aof the probe insertion hole14such that the plugging body50constitutes a portion of the housing12.

According to this processing method, the probe insertion hole14of the housing12can be plugged up by the plugging body50, and thus the internal components in the housing12can be protected from a foreign object, such as dust. In addition, the plugging body50is formed integrally with the peripheral portion of the probe insertion hole14in the housing12, and thus a dedicated component for the plugging body50is not necessary. Accordingly, the number of components of the actuator10can be reduced, and thus the manufacturing cost can be reduced while the management of the components is simplified.

The convex portion14bis formed at the peripheral portion of the probe insertion hole14of the housing12, and thus the amount of material for plugging up the probe insertion hole14can be secured with ease. Accordingly, the probe insertion hole14can be plugged up by melting the peripheral portion14aof the probe insertion hole14while the peripheral portion14aof the probe insertion hole14is prevented from becoming excessively thin. It should be noted that, when the probe insertion hole14is to be plugged up, the convex portion14bthat constitutes a portion of the peripheral portion14aof the housing12is heated and melted, and the resulting molten resin is made to flow into the probe insertion hole14.

In addition, the concave portion14cis formed in the front side surface portion12aof the housing12at a portion surrounding the root portion of the convex portion14b,and thus this configuration provides the following advantage. Consider a case in which the convex portion14bis melted and the molten resin is made to flow into the probe insertion hole14. In this case, the concave portion14cserves a function of accepting the molten resin that is to flow around the probe insertion hole14instead of flowing into the probe insertion hole14. This configuration can reduce the molten resin broadly spreading around the probe insertion hole14on the outer surface of the housing12and can make the appearance of the melted portion less noticeable after the probe insertion hole14is plugged up.

Second Embodiment

FIG. 11is a sectional view illustrating an actuator10according to a second embodiment.FIG. 11illustrates a section as viewed from the same viewpoint as that ofFIG. 10B.

FIG. 10Billustrates an example in which the plugging body50for plugging the probe insertion hole14is constituted by a portion of the housing12. Aside from this configuration, the plugging body50may be constituted by a lid member52that is separate from the housing12. The lid member52includes a lid portion52athat plugs up the probe insertion hole14and a head portion52bthat engages with the peripheral portion14aof the probe insertion hole14. The lid portion52aof the lid member52is inserted into the probe insertion hole14from the outside of the housing12so as to plug up the probe insertion hole14.

AlthoughFIG. 10Billustrates an example in which the convex portion14band the concave portion14care formed at the peripheral portion of the probe insertion hole14, the convex portion14band the concave portion14care not formed in the present example.

Third Embodiment

FIG. 12is a block diagram illustrating functionality of an actuator10and an inspection apparatus200according to a third embodiment.FIG. 13is a schematic diagram illustrating a configuration of a portion around the connector portion12gof the actuator10according to the third embodiment.

The first embodiment describes an example in which an insertion hole into which the probe202is inserted is the probe insertion hole14. The present embodiment differs from the first embodiment in that an insertion hole into which the probe202is inserted is the connector insertion hole12h.Inside the housing12, the control board26and the probe abutting portion44bbof the auxiliary transmission pattern44bthat constitutes a portion of the transmission path48is disposed on the inner side of the housing12relative to the connector insertion hole12h.

In addition to the ground line208a,the power-supply line208b,and the communication line208c,the probe202is inserted into the external connector204of the inspection apparatus200. The lines208a-208care omitted inFIG. 13. When the external connector204is mounted to the connector portion12gof the housing12, the lines208a-208cbecome having electrically continuity with the connector terminals28a-28con the control board26, and the leading end portion of the probe202makes contact with the probe abutting portion44bbon the control board26. With the actuator10according to the present embodiment as well, the effects similar to those in (A)-(E) described above can be obtained.

Thus far, the present invention has been described on the basis of the embodiments, but the embodiments merely describe the principle and the applications of the present invention. In addition, a number of modifications or arrangement changes can be made to the embodiments within the scope that does not depart from the spirit of the present invention set forth in the claims.

The actuator10may be used in an in-vehicle system, such as a vehicular air conditioning apparatus or a power window, or may be used for a purpose other than a vehicle. The electric motor16may be an AC motor, a servomotor, a stepping motor, or the like, instead of a DC motor. An example in which the control portion38and the communication portion36on the control board26are constituted by a single circuit element (IC chip34) has been described. Alternatively, the control portion38and the communication portion36may be constituted by separate circuit elements.

An example in which the rotation sensor22is constituted by a potentiometer has been described. Alternatively, the rotation sensor22may be constituted by a rotary encoder or the like. In addition, although an example in which a sensor to be inspected is the rotation sensor22has been described, this is not a limiting example. For example, a sensor to be inspected may be a temperature sensor, a pressure sensor, a humidity sensor, or the like. In any case, a sensor to be inspected may be a sensor that detects a physical quantity.

An example in which the transmission path48capable of continuously transmitting a detection signal generated by the sensor includes the conductor patterns42and44on the control circuit board26has been described. The transmission path48, however, is not limited to the conductor patterns and may be a terminal of the output sensor terminal24c.This terminal is a molding made of conductor. When the transmission path48is a terminal, the probe abutting portion44bbhaving a greater width than a portion of the terminal may be formed in adjacent to that portion. When the transmission path48is a terminal as well, a primary transmission path and an auxiliary transmission path may be formed. An example in which the transmission path48is formed outside the sensor has been described. Alternatively, the transmission path48may be formed inside the sensor. An example in which the probe abutting portion44bbis formed at the leading end portion of the auxiliary transmission path has been described. Alternatively, the probe abutting portion44bbmay be formed at a position midway in the auxiliary transmission path or may be formed in the primary transmission path.

The measuring device210may be equipped with a function of carrying out determination processing of determining whether the signal level of a detection signal is within a predetermined range. In this case, the processing result of the determination processing may be displayed in the display portion of the measuring device210, and thus the operator can check the signal level of the detection signal.

In the third embodiment, an example in which the probe202is inserted into the external connector204of the inspection apparatus200and the leading end portion of the probe202is brought into contact with the auxiliary transmission pattern44bon the control board26so as to take out the detection signal of the sensor has been described. Aside from this configuration, a detection signal terminal for taking out a detection signal may be connected to the control board26or the like along with the other connector terminals28a-28c,and the probe202in the external connector204may be brought into contact with this detection signal terminal so as to take out the detection signal of the sensor. In this case, the detection signal terminal constitutes a portion of the transmission path capable of continuously transmitting a detection signal of the sensor. In addition, to bring the detection signal terminal and the probe202in the external connector204into contact with each other, one of the two may be formed as a male terminal and the other one may be formed as a female terminal, and the two may be fitted together to retain their positions.