Patent Publication Number: US-2020276523-A1

Title: Pressure control device

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present invention claims priority under 35 U.S.C. § 119 to Japanese Application No. 2019-035165 filed on Feb. 28, 2019 the entire content of which is incorporated herein by reference. 
     BACKGROUND 
     Technical Field 
     The disclosure relates to a pressure control device. 
     Description of Related Art 
     As a hydraulic pressure control device that controls hydraulic pressure, for example, a hydraulic pressure control device provided for a clutch and mounted in an automobile is known. 
     It should be noted that the introduction in Background is merely provided for the convenience of clearly and comprehensively describing the technical solutions of the disclosure and facilitating the understanding of those skilled in the art. These technical solutions shall not be deemed well-known by those skilled in the art simply for having been described in Background. 
     However, in the hydraulic pressure control device recited in the conventional technology, there is a tendency that, as the channel becomes thinner, that is, as the width of the channel becomes smaller, the process of inserting the filter to the channel becomes more difficult to perform. Therefore, the issue that the process for assembling the body and the filter becomes less efficient may arise. 
     SUMMARY 
     According to an aspect of the disclosure, a pressure control device includes: a body having groove-like channel containing a groove part and a widened part which is connected with the groove part and of which a width is increased from the groove part; a filter unit, which is a filter unit that captures a foreign matter mixed in a fluid passing through the groove-like channel and has a cylindrical frame formed of an elastic material and comprising a through hole part penetrating in a direction orthogonal to a central axis of the frame and a plate-shaped filter member disposed to cover the through hole part and supported on an inner side of the frame, wherein the filter unit is accommodated in the widened part with a direction of the central axis of the frame being arranged along a depth direction of the widened part; and a plate-like member installed to the body to cover the groove-like channel in a state in which the filter unit is accommodated in the widened part. The frame has a length along the central axis greater than a depth of the widened part. 
     The above and other elements, features, steps, characteristics and advantages of the present disclosure will become more apparent from the following detailed description of the preferred embodiments with reference to the attached drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an oblique view illustrating a pressure control device according to an embodiment of the disclosure. 
         FIG. 2  is an exploded oblique view of the pressure control device shown in  FIG. 1 . 
         FIG. 3  is a cross-sectional view along III-III of  FIG. 1 . 
         FIG. 4  is a view illustrating the pressure control device of  FIG. 1  from the front side. 
         FIG. 5  is an oblique view illustrating a longitudinal section of a portion of the pressure control device shown in  FIG. 1 . 
         FIG. 6  is a view of  FIG. 5  when viewed from the top side. 
         FIG. 7  is a view illustrating a cross-sectional view along VI-VI of  FIG. 5  (in a state in which a separate plate is installed to a body). 
         FIG. 8  is an exploded oblique view of the pressure control device shown in  FIG. 5 . 
         FIG. 9  is a cross-sectional view along VIII-VIII of  FIG. 8 . 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     The foregoing and other features of the disclosure will become apparent from the following specification with reference to the accompanying drawings. Specific embodiments of the disclosure are disclosed in the specification and the accompanying drawings. The specification and the accompanying drawings describe several embodiments to which the principles of the disclosure are applicable. However, it should be understood that, the disclosure is not limited to the embodiments described herein, but shall include all modifications, variations and equivalents falling within the scope of the appended claims. 
     Hereinafter, a pressure control device of the disclosure will be described in detail based on preferred embodiments shown in the accompanying drawings. In the respective drawings, the Z-axis direction is set as a up-down direction Z. The X-axis direction is set as a left-right direction X among the horizontal directions orthogonal to the up-down direction Z. The Y-axis direction is set as an axis direction Y orthogonal to the left-right direction X among the horizontal directions orthogonal to the up-down direction Z. The positive side in the up-down direction Z is referred to as “upper side”, and the negative side is referred to as “lower side”. The positive side in the axis direction Y is referred to as “front side”, and the negative side is referred to as “rear side”. The front side is equivalent to one side of the axis direction, and the rear side is equivalent to the other side of the axis direction. In the embodiment, the depth direction of a groove part is set as the up-down direction, and the up-down direction is set as the Z-axis direction. In addition, the width direction of the groove part, which is orthogonal to the Z-axis direction, is set as the X-axis direction. Moreover, the length direction (longitudinal direction) of the groove part, which is orthogonal to the Z-axis direction and the X-axis direction respectively, that is, the flow direction of a flowing body, is set as the Y-axis direction. Therefore, “upper side”, “lower side”, “front side”, “rear side”, “up-down direction”, and “left-right direction” are merely terms for describing the relative position relationships of the respective parts. The actual arrangement relationship or the like may also be an arrangement relationship or the like other than the arrangement relationship indicated by these terms. In addition, “plan view” refers to a state of viewing the lower side from the upper side. 
     In addition, the embodiments of the pressure control device of the disclosure will be described with reference to  FIGS. 1 to 9 . A pressure control device  10  of the embodiment shown in  FIG. 1  and  FIG. 2  is, for example, a control valve mounted in a vehicle. The pressure control device  10  includes an oil channel body  20 , a spool valve  30 , a magnet holder  80 , a magnet  50 , an elastic member  70 , a fixing member  71 , and a sensor module  40 . 
     As shown in  FIG. 3 , the inside of the oil channel body  20  is provided with an oil channel  10   a  through which oil flows. A portion of the oil channel  10   a  indicated in  FIG. 3  is a portion of a spool hole  23  described afterwards. In the respective drawings, for example, a state in which a portion of the oil channel body  20  is cut out is shown. As shown in  FIG. 1 , the oil channel body  20  has a lower body  21  and an upper body  22 . While omitted in the drawings, the oil channel  10   a  is provided on both the lower body  21  and the upper body  22 . 
     The lower body  21  has a lower body main body  21   a  and a separate plate  21   b  disposed to overlap the upper side of the lower body main body  21   a . In the embodiment, the upper surface of the lower body  21  is equivalent to the upper surface of the separate plate  21   b  and is orthogonal to the up-down direction Z. The upper body  22  is disposed to overlap the upper side of the lower body  21 . The lower surface of the upper body  22  is orthogonal to the up-down direction Z. The lower surface of the upper body  22  contacts the upper surface of the lower body  21 , that is, the upper surface of the separate plate  21   b.    
     As shown in  FIG. 3 , the upper body  22  has the spool hole  23  extending in the axis direction Y. In the embodiment, the shape of the section of the spool hole  23  orthogonal to the axis direction Y is a circular shape centering at a central axis J. The central axis J extends in the axis direction Y. A radial direction centering at the central axis J is simply referred to as “radial direction”, and a circumferential direction centering at the central axis J is simply referred to as “circumferential direction”. 
     The spool hole  23  at least opens on the front side. In the embodiment, the rear end of the spool hole  23  is closed. That is, the spool hole  23  is a hole that is open on the front side and has a bottom part. The spool hole  23 , for example, may also open on two sides in the axis direction Y. At least a portion of the spool hole  23  forms a portion of the oil channel  10   a  inside the oil channel body  20 . 
     The spool hole  23  has a spool hole main body  23   a  and a guiding hole part  23   b . While omitted in the drawings, the oil channel  10   a  disposed at portions other than the spool hole  23  in the oil channel body  20  opens on the inner circumferential surface of the spool hole main body  23   a . The inner diameter of the guiding hole part  23   b  is greater than the inner diameter of the spool hole main body  23   a . The guiding hole part  23   b  is connected with the end part on the front side of the spool hole main body  23   a . The guiding hole part  23   b  is the end part on the front side of the spool hole  23  and opens on the front side. 
     As shown in  FIG. 1 , the spool hole  23  has a groove part  24  that is recessed from the inner circumferential surface of the spool hole  23  to the radially outer side and extends along the axis direction Y. In the embodiment, a pair of groove parts  24  are provided to sandwich the central axis J. The pair of groove parts  24  are recessed from the inner circumferential surface of the guiding hole part  23   b  toward the two sides of the left-right direction X. The groove part  24  is provided from the end part on the front side on the inner circumferential surface of the guiding hole part  23   b  till the end part on the rear side on the inner circumferential surface of the guiding hole part  23   b . As shown in  FIG. 4 , an inner side surface  24   a  of the groove part  24 , when viewed from the front side, is in a semi-circular shape concave from the inner circumferential surface of the guiding hole part  23   b  to the radially outer side. 
     As shown in  FIG. 3 , the upper body  22  has through holes  22   a ,  22   b , and  22   c  at the end part on the front side of the upper body  22 . The through hole  22   a  penetrates, in the up-down direction Z, a portion from the upper surface of the upper body  22  till the inner circumferential surface of the guiding hole part  23   b  in the upper body  22 . The through hole  22   b  penetrates, in the up-down direction Z, a portion from the lower surface of the upper body  22  till the inner circumferential surface of the guiding hole part  23   b  in the upper body  22 . As shown in  FIG. 1 , when viewed from the top side, the through hole  22   a  and the through hole  22   b  are in a rectangular shape that is elongated in the left-right direction X. When viewed from the top side, the through hole  22   a  and the through hole  22   b  are overlapped with each other. 
     As shown in  FIG. 3 , the through hole  22   c  penetrates, in the axis direction Y, a portion from the front surface of the upper body  22  till the through hole  22   b  in the upper body  22 . The through hole  22   c  is provided at the lower end part on the front surface of the upper body  22 . The through hole  22   c  opens on the lower side. As shown in  FIG. 4 , when viewed from the front side, the through hole  22   c  is in a rectangular shape that is elongated in the left-right direction X. The centers of the through holes  22   a ,  22   b , and  22   c  in the left-right direction X are, for example, at the same position as the central axis J in the left-right direction X. 
     As shown in  FIG. 1 , the portion in which the spool hole  23  is provided in the upper body  22  protrudes toward the upper side with respect to other portions of the upper body  22 . In the protruding portion, the upper surface at the end part on the front side is a curved surface that is in a semi-circular shape that protrudes toward the upper side. The through hole  22   a  opens at the upper end part of the semi-circular curved surface. The lower body main body  21   a , the separate plate  21   b , and the upper body  22  are, for example, respectively individual components. The lower body main body  21   a , the separate plate  21   b , and the upper body  22  are made of non-magnetic bodies. 
     As shown in  FIG. 3 , the spool valve  30  is disposed along the central axis J extending in the axis direction Y intersecting the up-down direction Z. The spool valve  30  is in a columnar shape. The spool valve  30  is attached to the oil channel body  20 . The spool valve  30  is movably disposed inside the spool hole  23  in the axis direction Y. 
     The spool valve  30  moves inside the spool hole body  23   a  in the axis direction Y to open and close the opening part of the oil channel  10   a  that opens on the inner circumferential surface of the spool hole body  23   a . While not shown in the drawings, at the end part on the rear side of the spool valve  30 , a forward force is applied from the hydraulic pressure of the oil or a driving device such as a solenoid actuator, etc. The spool valve  30  has a support part  31   a , a plurality of large diameter parts  31   b , and a plurality of small diameter parts  31   c . The respective parts of the spool valve  30  are in a columnar shape centering at the central axis J and extending in the axis direction Y. 
     The support part  31   a  is the end part on the front side of the spool valve  30 . The end part on the front side of the support part  31   a  supports the end part on the rear side of the magnet holder  80 . The end part on the rear side of the support part  31   a  is connected with the end part on the front side of the large diameter part  31   b.    
     The large diameter parts  31   b  and the small diameter parts  31   c  are alternately and continuously disposed from the large diameter part  31   b  connected with the end part on the rear side of the support part  31   a  toward the rear side. The outer diameter of the large diameter part  31   b  is greater than the outer diameter of the small diameter part  31   c . In the embodiment, the outer diameter of the support part  31   a  and the outer diameter of the small diameter part  31   c  are, for example, the same. The outer diameter of the large diameter part  31   b  is about the same as the inner diameter of the spool hole body  23   a  and is only slightly smaller than the inner diameter of the spool hole body  23   a . The large diameter part  31   b  is able to move in the axis direction Y while sliding with respect to the inner circumferential surface of the spool hole body  23   a . The large diameter part  31   b  functions as a valve part that opens and closes the opening part of the oil channel  10   a  opening on the inner circumferential surface of the spool hole body  23   a . In the embodiment, the spool valve  30  is, for example, an individual component made of metal. 
     The magnet holder  80  is disposed on the front side of the spool valve  30 . The magnet holder  80  is disposed to be movable in the axis direction Y inside the guiding hole part  23   b . The spool valve  30  and the magnet holder  80  are allowed to rotate relative to each other about the central axis. As shown in  FIG. 2 , the magnet holder  80  has a holder body part  81  and an opposing part  82 . 
     The holder body part  81  is in a stepped columnar shape centering at the central axis J and extending in the axis direction Y. As shown in  FIG. 3 , the holder body part  81  is disposed inside the spool hole  23 . More specifically, the holder body part  81  is disposed inside the guiding hole part  23   b . The holder body part  81  has a sliding part  81   a  and a supported part  81   b . That is, the magnet holder  80  has the sliding part  81   a  and the supported part  81   b.    
     The outer diameter of the sliding part  81   a  is greater than the outer diameter of the large diameter part  31   b . The outer diameter of the sliding part  81   a  is about the same as the inner diameter of the guiding hole part  23   b  and is only slightly smaller than the inner diameter of the guiding hole part  23   b . The sliding part  81   a  is able to move in the axis direction Y while sliding with respect to the inner circumferential surface of the spool hole  23 , that is, the inner circumferential surface of the guiding hole part  23   b  in the embodiment. The radially outer edge part of the surface on the rear side of the sliding part  81   a  is able to contact a step surface toward the front side which generates a step difference between the spool body part  23   a  and the guiding hole part  23   b . In this way, the movement of the magnet holder  80  from the position at which the magnet holder  80  contacts the step surface toward the rear side can be suppressed and the rearmost position of the magnet holder  80  can be determined. Since the spool valve  30  receives a force toward the rear side from the elastic member  70  via the magnet holder  80 , as will be described afterwards, by determining the rearmost position of the magnet holder  80 , the rearmost position of the spool valve  30  can be determined. 
     The supported part  81   b  is connected with the end part on the rear end of the sliding part  81   a . The outer diameter of the supported part  81   b  is smaller than the outer diameter of the sliding part  81   a  and the outer diameter of the large diameter part  31   b , and is greater than the outer diameter of the support part  31   a  and the outer diameter of the small diameter part  31   c . The supported part  81   b  is movable inside the spool hole body  23   a . The supported part  81   b , together with the movement of the spool valve  30  in the axis direction Y, moves in the axis direction Y between the guiding hole part  23   b  and the spool hole body  23   a.    
     The supported part  81   b  has a supported concave part  80   b  that is recessed from the end part on the rear end of the supported part  81   b  to the front side. The support part  31   a  is inserted into the supported concave part  80   b . The end part on the front end of the support part  31   a  contacts the bottom surface of the supported concave part  80   b . In this way, the magnet holder  80  is supported from the rear side by the spool valve  30 . The size of the supported part  81   b  in the axis direction Y is, for example, smaller than the size of the sliding part  81   a  in the axis direction Y. 
     As shown in  FIG. 2 , the opposing part  82  protrudes from the holder body part  81  to the radially outer side. More specifically, the opposing part  82  protrudes from the sliding part  81   a  to the radially outer side. In the embodiment, a pair of opposing parts  82  are provided to sandwich the central axis J. The pair of opposing parts  82  protrude from the outer circumferential surface of the sliding part  81  to the two sides of the left-right direction X. The opposing part  82  extends in the axis direction Y from the end part on the front end side of the sliding part  81   a  till the end part on the rear side of the sliding part  81   a . As shown in  FIG. 4 , the opposing part  82 , when viewed from the front side, is in a semi-circular shape convex toward the radially outer side. 
     The pair of opposing parts  82  are fit with the pair of groove parts  24 . The opposing part  82  is opposite to the inner side surface  24   a  of the groove part  24  and is able to contact the inner side surface  24   a . The description “two parts are opposite in the circumferential direction” in the specification may be construed as both of the two parts being located along the circumferential direction on a hypothetical circle and opposite to each other. 
     As shown in  FIG. 3 , the magnet holder  80  has a first concave part  81   c  that is recessed from the outer circumferential surface of the sliding part  81   a  to the radially inner side. In  FIG. 3 , the first concave part  81   c  is recessed from the upper end part of the sliding part  81   a  toward the lower side. The inner side surface of the first concave part  81   c  includes a pair of surfaces opposite to each other in the axis direction Y. 
     The magnet holder  80  has a second concave part  80   a  recessed from the end part on the front side in the magnet holder  80  to the rear side. The second concave part  80   a  extends from the sliding part  81   a  till the supported part  81   b . As shown in  FIG. 2 , the second concave part  80   a , when viewed from the front side, is in a circular shape centering at the central axis J. As shown in  FIG. 3 , the inner diameter of the second concave part  80   a  is greater than the inner diameter of the supported concave part  8 . 
     The magnet holder  80 , for example, may be made of resin or metal. In the case where the magnet holder  80  is made of resin, the magnet holder  80  can be easily manufactured. In addition, the manufacturing cost of the magnet holder  80  can be reduced. In the case where the magnet holder  80  is made of metal, the size accuracy of the magnet holder  80  can be increased. 
     As shown in  FIG. 2 , the magnet  50  is substantially in a rectangular parallelepiped shape. The upper surface of the magnet  50  is, for example, a curved surface in a circular shape along the circumferential direction. As shown in  FIG. 3 , the magnet  50  is accommodated inside the first concave part  81   c  and fixed to the holder main body  81 . In this way, the magnet  50  is fixed to the magnet holder  80 . The magnet  50  is, for example, fixed by an adhesive. The radially outer surface of the magnet  50  is, for example, located radially inward with respect to the outer circumferential surface of the sliding part  81   a . The radially outer surface of the magnet  50  is opposite to the inner circumferential surface of the guiding hole part  23   b  via a gap in the radial direction. 
     As described above, the sliding part  81   a  provided in the first concave part  81   c  moves while sliding with respect to the inner circumferential surface of the spool hole  23 . Therefore, the outer circumferential surface of the sliding part  81   a  and the inner circumferential surface of the spool hole  23  contact each other or opposite to each other via a small gap. In this way, it is difficult for foreign matters, such as metal pieces, included in the oil to enter the first concave part  81   c . Therefore, the foreign matters, such as metal pieces, included in the oil can be suppressed from being attached to the magnet  50  accommodated in the first concave part  81   c . Since the size accuracy of the sliding part  81   a  can be increased in the case where the magnet holder  80  is made of metal, it is even more difficult for foreign matters, such as metal pieces, included in the oil to enter the first concave part  81   c.    
     As shown in  FIG. 2 , the fixing member  71  is a plate surface in a plate shape parallel to the left-right direction X. The fixing member  71  has an extending part  71   a  and a bent part  71   b . The extending part  71   a  extends in the up-down direction Z. The extending part  71   a , when viewed from the front side, is in a rectangular shape that is elongated in the up-down direction Z. As shown in  FIG. 1  and  FIG. 3 , the extending part  71   a  is inserted into the guiding hole part  23   b  via the through hole  22   b . The upper end part of the extending part  71   a  is inserted into the through hole  22   a . The extending part  71   a  blocks a portion of the opening on the front side of the guiding hole part  23   b . The bent part  71   b  is bent from the end part on the lower side of the extending part  71   a  to the front side. The bent part  71   b  is inserted into the through hole  22   c . The fixing member  71  is disposed on the front side of the elastic member  70 . 
     In the embodiment, the fixing member  71  is inserted from the opening part of the through hole  22   b  that opens on the lower surface of the upper body  22  to the through hole  22   a  via the through hole  22   b  and the guiding hole part  23   b  before the upper body  22  and the lower body  21  are overlapped. Then, as shown in  FIG. 1 , by stacking in the up-down direction Z to assemble the upper body  22  and the lower body  21 , the bent part  71   b  inserted into the through hole  22   c  is supported from the lower side by the upper surface of the lower body  21 . In this way, the fixing member  71  can be attached to the oil channel body  20 . 
     As shown in  FIG. 3 , the elastic member  70  is a coil spring extending in the axis direction Y. The elastic member  70  is disposed on the front side of the magnet holder  80 . In the embodiment, at least a portion of the elastic member  70  is disposed inside the second concave part  80   a . Therefore, at least a portion of the elastic member  70  can be overlapped with the magnet holder  80  in the radial direction, and the size of the pressure control device  10  in the axis direction Y can be easily miniaturized. In the embodiment, the portion on the rear side of the elastic member  70  is disposed inside the second concave part  80   a.    
     The end part on the rear side of the elastic member  70  contacts the bottom surface of the second concave part  80   a . The end part on the front side of the elastic member  70  contacts the fixing member  71 . In this way, the end part on the front side of the elastic member  70  is supported by the fixing member  71 . The fixing member  71  receives an elastic force from the elastic member  70  toward the front side, and the extending part  71   a  is pressed to the inner side surface on the front side of the through holes  22   a  and  22   b.    
     With the end part on the front side of the elastic member  70  being supported to the fixing member  71 , the elastic member  70  applies an elastic force toward the rear side to the spool valve  30  via the magnet holder  80 . Therefore, for example, the position of the spool valve  30  in the axis direction Y can be maintained at a position where the hydraulic pressure of the oil applied to the end part on the rear side of the spool valve  30  or the force applied from a driving device such as a solenoid actuator balances the elastic force of the elastic member  70 . In this way, by changing the force applied to the end part on the rear side of the spool valve  30 , the position of the spool valve  30  in the axis direction Y can be changed, and the on/off of the oil channel  10   a  inside the oil channel body  20  can be switched. 
     In addition, with the hydraulic pressure of the oil applied to the end part on the rear side of the spool valve  30  or the force applied from a driving device such as a solenoid actuator, as well as the elastic force of the elastic member  70 , the magnet holder  80  and the spool valve  30  can be pressed against each other in the axis direction Y. Therefore, the magnet holder  80  allows relative rotation with respect to the spool valve  30  about the central axis and moves in the axis direction Y together with the movement of the spool valve  30  in the axis direction Y. 
     The sensor module  40  has a housing  42  and a magnetic sensor  41 . The housing  42  accommodates the magnetic sensor  41 . As shown in  FIG. 1 , the housing  42  is, for example, in a rectangular box shape flat in the up-down direction Z. The housing  42  is fixed on a flat surface, in the upper surface of the upper body  22 , located on the rear side of the semi-circular shaped curved surface on which the through hole  22   a  is provided. 
     As shown in  FIG. 3 , the magnetic sensor  41  is fixed to the bottom surface of the housing  42  inside the housing  42 . In this way, the magnetic sensor  41  is attached to the oil channel body  20  via the housing  42 . The magnetic sensor  41  detects a magnetic field of the magnet  50 . The magnetic sensor  41  is, for example, a Hall element. The magnetic sensor  41  may also be a magnetic resistance element. 
     As the position of the magnet  50  in the axis direction Y changes with the movement of the spool valve  30  in the axis direction Y, the magnetic field of the magnet  50  passing through the magnetic sensor  41  changes. Therefore, by detecting changes of the magnetic field of the magnet  50  by the magnetic sensor  41 , the position of the magnet  50  in the axis direction Y, that is, the position of the magnet holder  80  in the axis direction Y, can be detected. Accordingly, as described above, the magnet holder  80  moves in the axis direction Y together with the movement of the spool valve  30  in the axis direction Y. Therefore, by detecting the position of the magnet holder  80  in the axis direction Y, the position of the spool valve  30  in the axis direction Y can be detected. 
     The magnetic sensor  41  and the magnet  50  are overlapped in the up-down direction Z. That is, at least a portion of the magnet  50  overlaps the magnetic sensor  41  in a direction parallel to the up-down direction Z in the radial direction. Therefore, the magnetic field of the magnet  50  is easily detected by the magnetic sensor  41 . Therefore, with the sensor module  40 , the position change of the magnet holder  80  in the axis direction Y, that is, the position change of the spool valve  30  in the axis direction Y, can be more accurately detected. 
     The description “at least a portion of the magnet overlaps the magnetic sensor in the radial direction” in the specification indicates that it is acceptable as long as at least a portion of the magnet overlaps the magnetic sensor in the radial direction in the position of at least a portion within the range in which the spool valve to which the magnet is directly fixed moves in the axis direction. That is, for example, when the spool valve  30  and the magnet holder  80  change the positions in the axis direction Y from the positions of  FIG. 3 , it may also be that the magnet  50  does not overlap the magnetic sensor  41  in the up-down direction Z. In the embodiment, if the magnet  50  is within the range in which the spool valve  30  moves in the axis direction Y, at any position, a portion of the magnet  50  overlaps the magnetic sensor  41  in the up-down direction. 
     The pressure control device  10  includes a rotation stopping part. The rotation stopping part is a portion able to contact the magnet holder  80 . In the embodiment, the rotation stopping part is the inner side surface  24   a  of the groove part  24 . That is, the opposing part  82  is opposite to the inner side surface  24   a , which is the rotation stopping part, in the circumferential direction and is able to contact the inner side surface  24   a.    
     Therefore, according to the embodiment, for example, in the case where the opposing part  82  rotates about the central axis J, the opposing part  82  contacts the inner side surface  24   a  which is the rotation stopping part. In this way, the rotation of the opposing part  82  is suppressed by the inner side surface  24   a , and the rotation of the magnet holder  80  about the central axis J is suppressed. Therefore, the deviation of the position of the magnet  50  fixed to the magnet holder  80  in the circumferential direction can be suppressed. Consequently, in the case where the position of the spool valve  30  in the axis direction Y does not change, even if the spool valve  30  rotates about the central axis J, the changes of the position information of the magnet  50  in the axis direction Y that is detected by the magnetic sensor  41  can be suppressed. In this way, the changes of the position information of the spool valve  30  can be suppressed, and the accuracy for grasping the position of the spool valve  30  in the axis direction Y can be increased. 
     In the embodiment, the rotation stopping part is the inner side surface  24   a  of the groove part  24 . Therefore, it is not necessary to prepare a separate component as the rotation stopping part, and the number of parts of the pressure control device  10  can be reduced. In this way, the work required to assemble the pressure control device  10  and the manufacturing cost of the pressure control device  10  can be reduced. 
     As described above, there are cases in which the oil passing through the pressure control device  10  contains foreign matters such as metal pieces. It is preferable that such foreign matters are captured in the process in which the oil passes through the pressure control device  10  and are prevented from further flowing to the downstream side. Here, the pressure control device  10  is configured to be able to capture foreign matters. In the following, the configuration and the function are described with reference to  FIG. 5  to  FIG. 9 . 
     While the pressure control device  10  is suitable for a hydraulic pressure control device controlling the pressure of the oil in the embodiment, the pressure control device  10  is not limited thereto. Examples of devices for which the pressure control device  10  is suitable include, for example, in addition to the hydraulic pressure control device, fluid devices such as a water pressure control device that controls the pressure of water and an air pressure control device that controls the pressure of air. In such case, those passing through the pressure control device  10  are fluids such as oil, water, air, and are generally referred to as “fluid” in the following descriptions. In addition, the direction in which the fluid flows is referred to as “flowing direction Q”. 
     The pressure control device  10 , as shown in  FIG. 5 , further includes a filter unit  9  attached to a body  3  in addition to the spool valve  30 , the magnet holder  80 , the magnet  50 , the elastic member  70 , the fixing member  71 , the sensor module  40 , etc., as described above. 
     The body  3  can be at least one of the lower body  21  and the upper body  22  forming the oil channel  20 . As shown in  FIGS. 5 to 7 , the body  3  has a groove-like channel  30  which is recessed on the upper surface (a surface)  30  and through which the fluid passes through along the flowing direction Q. The groove-like channel  33  contains a groove part  31  and a widened part  32  connected with the groove part  31 , and forms a portion of the oil channel  10   a.    
     The groove part  31  has a bottom part (first bottom part)  311 , a sidewall part  312  located on one side of the bottom part  311  when viewed from the upstream toward the downstream of the flow of the fluid, and a sidewall part  313  located on the other side of the bottom part  311 . A border part  314  of the bottom part  311  and the sidewall part  312  as well as a border part  315  of the bottom part  311  and the sidewall part  313  are preferably arced, as shown in  FIG. 5 . In this way, the fluid can smoothly pass through the vicinity of the border part  314  and the border part  315 . 
     While the groove part  31  is in a linear shape along the axis direction Y in the plan view of the body  3 , the disclosure is not limited thereto. It may also be that the groove part  31  has a part in which at least a portion thereof is curved. A width (first width) W 31  (referring to  FIG. 8 ) of the groove part  31 , which is the interval between the sidewall part  312  and the sidewall part  313  is approximately constant along the axis direction Y. In addition, a depth (first depth) D 31  (referring to  FIG. 7 ) of the groove part  31 , which is the depth from the surface  30  to the bottom part  311 , is also approximately constant along the axis direction Y. 
     The widened part  32  is disposed on the longitudinal direction of the groove-like channel  33 , that is, on the axis direction Y. The width of the widened part  32  is greater than the width W 31  of the groove part  31  from the surface  30  till the bottom part  311 , and the widened part  32  functions as an accommodating part accommodating the filter unit  9  that is cylindrical. A width W 32  (referring to  FIG. 8 ) of the widened part  32  is gradually increased from the upstream side toward the downstream side, that is, from the front side toward the rear side, and becomes gradually decreased toward the downstream side from the middle. Specifically, in the embodiment, the widened part  32  has a curved part  321  that is curved in a circular shape in the plan view. The widened part  32  in such shape can, for example, be processed by using an end mill. 
     As shown in  FIG. 7 , the width W 32  of the widened part  32  is maintained constant along the up-down direction Z, and a depth (second depth) D 32  from the surface  30  till a bottom surface (second bottom part)  341  becomes greater than the depth D 31  of the groove part  31 . The bottom part of the widened part  32  has a receiving part  34  into which a portion of the lower side of the filter unit  9  is inserted. Of course, the depth D 34  of the receiving part  34  is equal to the difference between the depth D 32  and the depth D 31 . 
     As shown in  FIGS. 5 and 7 , the filter unit  9  is accommodated in the widened part  32  with the direction of a central axis O 92  of a frame  92  being arranged along the direction of the depth D 32  of the widened part  32  (that is, the up-down direction Z). When the fluid passes through the groove-like channel  33 , the filter unit  9  can capture foreign matters mixed in the fluid. In this way, the filter unit  9  can prevent or suppress malfunctioning of the operation of the pressure control device  10  due to foreign matters. Examples of the malfunctioning include the obstruction of movement when the spool valve  30  moves in the spool hole  23 , etc. 
     The filter unit  9  has the cylindrical frame  92  and a filter member  93  that is plate-shaped and disposed on the inner side of the frame  92 . The filter member  93  is disposed along the direction of the central axis O 92  of the frame  92 , and the thickness direction thereof is parallel to the axis direction Y. In this way, the filter member  93  can face the fluid passing through the groove-like channel  33 . 
     The filter member  93  has a plurality of pores  931  penetrating in the thickness direction. The pores  931  are disposed at intervals along the left-right direction X as well as the up-down direction Z. The diameter of the pore  931  is set to be smaller than the diameter of an average foreign matter. In addition, in order not to obstruct the flow of the fluid, the total area of the pores  931  is preferably as great as possible, and the aperture ratio is also preferably as great as possible. With such pores  931 , the performance of capturing foreign matters by the filter unit  9  can be facilitated. 
     In addition, the filter member  93  is in a state of being supported on the inner side of the frame  92 . In this way, when the fluid passes through the filter member  93 , the filter member  93  is prevented from being deformed by the flow of the fluid. Thus, the foreign matters can be reliably captured by the filter member  93 . As a result, the performance of capturing foreign matters by the filter unit  9  can be further facilitated. 
     As shown in  FIG. 8 , a width W 93  of the filter member  93  is the same as the width W 31  of the groove part  31  located upstream of the widened part  32 . In this way, when the fluid passes through the filter member  93 , the capturing area in which the filter member  93  captures foreign matters can be ensured to be wide as possible. Consequently, the performance of capturing foreign matters by the filter unit  9  can be further facilitated. While the width W 93  is the same as the width W 31  in the embodiment, the disclosure is not limited thereto. For example, the width W 31  may also be greater. 
     As shown in  FIG. 7 , the frame  92  is cylindrical and includes a through hole part  921  penetrating in parallel with the axis direction Y orthogonal to the central axis O 92  of the frame  92 . While the external shape of the frame  92  is cylindrical in the embodiment, the disclosure is not limited thereto. The external shape of the frame  92  may also be rectangular cylindrical. Then, the filter member  93  is disposed to cover the through hole part  921  and is supported on the inner side of the frame  92 . In this way, the filter member  93  and the frame  92  are unitized and configured as one part, that is, the filter unit  9 . Here, the inner side of the frame  92  refers to the side facing the through hole part  921 , and the outer side of the frame  92  refers to the side facing the body  3  and the separate plate  21   b.    
     At the time of assembling the body  3  and the filter unit  9 , the assembling can be performed by simply inserting the filter unit  9  into the widened part  32 . In addition, as described above, the widened part  32  is wider than the groove part  31 . In this way, regardless of the size of the width W 31  of the groove part  31 , the filter unit  9  can be easily inserted into the widened part  32 . Thus, the workability at the time of assembling the body  3  and the filter unit  9  is improved. 
     As shown in  FIG. 8 , since the frame  92  is cylindrical, as described above, an outer circumferential part  922  of the frame  92  is arced in a circular shape. Meanwhile, in the widened part  32  accommodating the filter unit  9 , the curved shape of the curved part  321  is curved along the circular arc of the outer circumferential part  922 . In this way, at the time of assembling the body  3  and the filter unit  9 , the filter unit  9  can be easily inserted into the widened part  32 . 
     In addition, the cylindrical frame  92  has the outer circumferential part (torso part)  922 , a closed wall part  923  closing the upper side in the direction of the central axis O 92  of the outer circumferential part  922 , and a closed wall part  924  closing the lower side. In the state in which the filter unit  9  is accommodated in the widened part  32 , a portion of the lower side of the filter unit  9 , that is, the closed wall part  924  of the closed wall part  923  and the closed wall part  924 , can be inserted into the receiving part  34 . In the disclosure, the frame  92  is formed of an elastic material. 
     As shown in  FIG. 5 , in the state of being accommodated in the widened part  32 , the frame  92  (the filter unit  9 ) has a height to an extent of slightly protruding from the groove-like channel  30  toward the upper side. That is, a length H 92  (a distance from an upper surface  923   a  till a lower surface  924   a  of the frame  92 ) along the central axis O 92  of the frame  92  is greater than the depth D 32  of the widened part  32 . Therefore, in the state in which the filter unit  9  is accommodated in the widened part  32 , when the separate plate (plate-like member)  21   b  is installed to the body  3  (the lower body main body  21   a ) to cover the groove-like channel  33 , the frame  92  are elastically deformed. In this way, the upper surface  923   a  of the frame  92  (the closed wall part  923 ) closely contacts the lower surface of the separate plate  21   b , and the lower surface  924   a  of the frame  92  (the closed wall part  924 ) closely contacts the bottom surface  341  of the widened part  32  (the receiving part  34 ). Thus, the fluid preferentially and smoothly passes through the through hole part  921  of the frame  92 . Accordingly, the property of capturing foreign matters by the filter member  93  can be properly exhibited. In the state in which the separate plate  21   b  is installed to the body  3 , as shown in  FIG. 7 , the height (the length of the frame  92  along the central axis O 92 ) H 92  of the frame  92  is about as large as the depth D 32  of the widened part  32 . 
     As described above, the pressure control device  10  is formed by inserting the closed wall part  924  of the filter unit  9  into the receiving part  34  of the widened part  32 . In other words, in the pressure control device  10 , a step difference  331  is created between (borders of) the bottom part  311  of the groove part  31  and the bottom surface  341  of the receiving part  34 , and the closed wall part  924  is disposed to resolve the step difference  331 . In this way, it becomes substantially difficult to generate a fluid flowing to bypass between the closed wall part  924  and the receiving part  34 . Therefore, the foreign matters can be prevented from flowing through the filter unit  9  to the downstream side. Since the frame  92  is formed of an elastic material, the closed wall part  924  can be elastically deformed to closely contact the receiving part  34 . 
     A thickness T 924  of the closed wall part  924  after elastic deformation is approximately the same as the depth D 34  of the receiving part  34 . In this way, it is difficult to create a step difference between the bottom part  311  of the groove part  31  and the closed wall part  924 . Therefore, the fluid can smoothly pass through the filter unit  9 . In addition, since the fluid can smoothly pass through, it is even more difficult to generate a flow of the fluid that bypasses between the closed wall part  924  and the receiving part  34 . In this way, the foreign matters can be more reliably prevented from flowing through the filter unit  9  to the downstream side. 
     Particularly, in the embodiment, the upper surface  923   a  and the lower surface  924   a  of the frame  92  (the end surfaces on two sides in the direction of the central axis O 92  of the frame  92 ) are flat surfaces and, as shown in  FIG. 9 , the receiving part  34  has the bottom surface  341  that is flat. Then, as shown in  FIG. 7 , in the state in which the filter unit  9  is accommodated in the widened part  32  and the separate plate  21   b  is installed to the upper surface  30  of the body  3 , the entirety of the upper surface  923   a  of the frame  92  contacts the lower surface of the separate plate  21   b , and the entirety of the lower surface  924   a  of the frame  92  contacts the bottom surface  341  of the widened part  32 . In this way, even in the state in which the fluid passes through the groove-like channel  33 , the posture of the filter unit  9  inside the widened part  32  is stable, so the filter unit  9  can stably capture foreign matters. 
     In addition, as shown in  FIGS. 5 and 6 , the frame  92  is provided with concave parts  925  on the upstream side and the downstream side, respectively. The concave part  925  is a portion where the outer circumferential part  922  of the frame  92  is concave along the up-down direction Z and toward the side of the through hole part  921 . In other words, the concave part  925  is also a thin part (diameter reduced part) in which the thickness of the frame  92  in the radial direction is reduced along the top-down direction Z. The concave part  925  functions as a deformation absorbing part absorbing deformation of the frame  92 . Therefore, when the filter unit  9  is accommodated in the widened part  32  and the separate plate  21   b  is installed to the body  3 , the frame  92  is elastically deformed so as to fill the gap between the concave part  925  and the widened part  32 . In this way, by making the outer circumferential part  922  of the frame  92  the shape along the inner circumferential surface of the widened part  32 , the tightness therebetween is facilitated. As result, the fluid can be more reliably prevented from flowing to the downstream side by passing through the lateral side of the frame  92 . 
     As shown in  FIGS. 5 to 7 , the filter unit  9  has a regulating part  95 , which, in the state in which the filter unit  9  is accommodated in the widened part  32 , regulates the arrangement direction with respect to the groove part  31  and prevents the filter unit  9  from rotating about the central axis O 92 . The regulating part  95  is formed by a pair of protruding parts  951  disposed to protrude as a block or a plate on the closed sidewall part  923 . One of the protruding parts  951  protrudes toward the groove part  31  located on the upstream side of the widened part  32 , that is, the front side in the axis direction Y, and the other protruding part  951  protrudes toward the groove part  31  located on the downstream side of the widened part  32 , that is, the rear side of the axis direction Y. 
     It may also be that the regulating part  95  does not have the pair of protruding parts  951 . For example, one of the protruding parts  951  may be omitted. In addition, it is preferable that a width W 951  of each of the protruding parts  951  is slightly smaller than the width W 31  of the groove part  31 . 
     Then, in the state in which the filter unit  9  is accommodated in the widened part  32 , each of the protruding parts  951  is disposed in the groove part  31 . In addition, at this time, there is also a case in which each of the protruding parts  951  abuts against at least one of the sidewall part  312  and the sidewall part  313  of the groove part  31 . With such protruding parts  951 , in the state of being accommodated in the widened part  32 , the arrangement direction of the filter unit  9  with respect to the groove part  31  is correctly regulated, so as to avoid the rotation about the central axis O 92 . In this way, regardless the size of the flow of the fluid, the filter member  93  can face the flowing direction Q of the fluid, and thus can stably capture foreign matters. 
     In addition, the regulating part  95  can be formed by the protruding parts  951  whose shape is simple, thereby contributing to the high efficiency at the time of manufacturing the filter unit  9 . In addition, by disposing the regulating part  95  at the closed wall part  923  of the frame  92 , the regulating part  95  can be disposed as close to the corner of the groove-like channel  33  as possible. Accordingly, the regulating part  95  can be prevented or suppressed from obstructing the flow of the fluid. 
     As shown in  FIG. 5 , the filter unit  9  has a detachment preventing part  94  that prevents the filter unit  9  from being detached from the widened part  32  after being inserted to the widened part  32 . The detachment preventing part  94  is configured to include a pair of flat protruding parts  942  which are disposed to protrude on the closed wall part  923  of the frame  92  and are in a flat shape. As shown in  FIG. 8 , one of the flat protruding parts  942  protrudes toward the left side of the left-right direction X, and the other flat protruding part  942  protrudes toward the right side of the left-right direction X. Then, in the state in which the filter unit  9  is accommodated in the widened part  32 , each of the flat protruding parts  942  is pressed against the widened part  32  in the protruding direction of the flat protruding part  942 . In this way, the filter unit  9  can be prevented from being detached from the widened part  32 . In the following, the effect resulting from the detachment preventing part  94  may be referred to as “detachment preventing effect”. With the detachment preventing effect, for example, even if the body  3  and the filter unit  9  in the assembled state are turned upside down or is subjected to vibration during transportation, the detachment of the filter unit  9  from the widened part  32 , which unintentionally decomposes the body  3  and the filter unit  9 , can be prevented. 
     In the filter unit  9  with the above configuration, for example, it is preferable that the frame  92  is formed of an elastic material (rubber material), and the filter member  93  is formed of a metal material. In this way, the filter unit  9  can be an insert molded product of the frame  92  and the filter member  93 . In this way, a higher efficiency at the time of manufacturing the filter unit  9  can be achieved. Specifically, by making the frame  92  cylindrical, the filter unit  9  can be easily molded. 
     While the embodiments, as shown, of the pressure control device of the disclosure are described above, the disclosure is not limited thereto. The respective parts forming the pressure control device can be replaced with any part of an arbitrary configuration having the same function. In addition, any arbitrary component may also be added. In addition, the filter member is not limited to being disposed along the direction of the central axis of the frame as in the above embodiment. For example, the filter member may also be disposed in an arched shape, and may also be bent in the shape of the letter “&lt;”. Moreover, the plate-shaped filter member may also be disposed to be inclined with respect to the central axis of the frame. Furthermore, the plate-like member installed to the body is not limited to a plate (separate plate), but may also be other bodies in which a channel is formed. 
     Features of the above-described preferred embodiments and the modifications thereof may be combined appropriately as long as no conflict arises. While preferred embodiments of the present disclosure have been described above, it is to be understood that variations and modifications will be apparent to those skilled in the art without departing from the scope and spirit of the present disclosure. The scope of the present disclosure, therefore, is to be determined solely by the following claims.