JP5328689B2 - Electrical contact protection structure of hydraulic control device - Google Patents

Description

  The present invention relates to an electrical contact protection structure for a hydraulic control apparatus driven by hydraulic pressure.

  2. Description of the Related Art Conventionally, a hydraulic control device that controls a friction engagement device such as a clutch or a brake is driven by hydraulic pressure for the purpose of detecting completion of oil filling in the friction engagement device (hereinafter referred to as “fill completion”). Are widely used (see, for example, Patent Document 1).

  Such a pressure switch includes a spool having a first electric pin, a receiving chamber for storing the spool, and a second electric pin provided in the receiving chamber corresponding to the first electric pin. The spool has a spool body that can slide by hydraulic pressure. The first electric pin is attached to the spool body. The second electric pin is connected to an electric circuit provided outside the accommodation chamber.

  When the filling is completed, the first electric pin comes into contact with the second electric pin by sliding the spool body. The completion of filling is detected by detecting a voltage change in the electric circuit at this time.

JP 2001-343032 A

  Here, for the purpose of smooth sliding of the spool body portion by hydraulic pressure, a minute gap is provided between the spool body portion and the inner wall of the storage chamber. Therefore, the oil leaked through the minute gap may adhere to the first electric pin or the second electric pin. Further, depending on the properties of the oil used, the oil may become dust due to discharge between the first electric pin and the second electric pin.

  In such a case, if the leaked oil or dust adheres to the electrical contact between the first electrical pin and the second electrical pin, the electrical connectivity between the first electrical pin and the second electrical pin decreases. Therefore, there is a possibility that the completion of fill cannot be accurately detected.

  The present invention has been made in view of the above-described situation, and an object thereof is to provide an electrical contact protection structure capable of suppressing the adhesion of oil and dust to electrical contacts in a hydraulic control device.

  An electrical contact protection structure of a hydraulic control device according to the present invention includes a housing, a storage chamber provided in the housing and having a first space and a second space separated from each other by an elastic isolation cover, and a first space. A spool body having a spool body portion slidable by hydraulic pressure, a first electric pin attached to the spool body portion and inserted through the isolation cover, and provided in the second space, corresponding to the first electric pin And a communication hole provided in the inner wall of the storage chamber and communicating with the first space and the second space.

  ADVANTAGE OF THE INVENTION According to this invention, the electrical contact protection structure which can suppress adhesion of the oil and dust to an electrical contact in a hydraulic control apparatus can be provided.

It is sectional drawing of the hydraulic control apparatus 100 which concerns on embodiment. It is an enlarged view of FIG. It is a top view from the arrow direction A of FIG. FIG. 3 is a plan view from an arrow direction B in FIG. 2. It is sectional drawing in CC line of FIG. It is sectional drawing in the DD line | wire of FIG. It is a time chart for demonstrating the hydraulic control method in the hydraulic control apparatus 100 which concerns on embodiment. It is sectional drawing of the hydraulic control apparatus 100 which concerns on embodiment. It is sectional drawing of the hydraulic control apparatus 100 which concerns on embodiment.

Next, embodiments of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, the drawings are schematic, and the ratio of each dimension may be different from the actual one. Accordingly, specific dimensions and the like should be determined in consideration of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.
(Configuration of hydraulic control device 100)
Hereinafter, a hydraulic control device 100 according to an embodiment will be described with reference to the drawings. Hereinafter, the hydraulic control device 100 used for a clutch as a friction engagement device will be described as an example. The clutch has a hydraulic chamber and is driven by supplying and discharging oil to the hydraulic chamber. In the following description, “up / down / left / right” represents “up / down / left / right in each figure”.

  FIG. 1 is a cross-sectional view of the hydraulic control device 100. As shown in FIG. 1, the hydraulic control device 100 includes a housing 10, a pressure control valve 15, an electromagnetic control valve 20, and a hydraulic switch 200.

  An input port 26, an output port 27, a first drain port 31, and a second drain port 32 are formed in the housing 10. The input port 26 is connected to an input circuit that is a flow path through which oil discharged from a hydraulic pump (not shown) passes. The output port 27 is connected to an output circuit which is a flow path through which oil sent to a hydraulic chamber of a clutch (not shown) passes. The first drain port 31 and the second drain port 32 are respectively connected to a tank (not shown) that collects oil discharged from the clutch.

  The pressure control valve 15 includes a first spool 34 that is slidable in the left-right direction in the housing 10. A valve chamber 35 is formed in the housing 10, and a substantially central portion of the first spool 34 is located in the valve chamber 35. A feedback chamber 36 is formed in the left end portion of the first spool 34. The valve chamber 35 and the feedback chamber 36 communicate with each other via a flow path 37 formed in the first spool 34. A spring 38 is provided between the feedback chamber 36 and the inner surface of the housing 10, and the first spool 34 is urged rightward by the spring 38. A pilot chamber 39 is formed in the right end portion of the first spool 34, and a pressure receiving surface 40 is formed on the right end surface of the first spool 34.

  When the first spool 34 is positioned at the right end (position where it abuts on a valve seat body 41 of the electromagnetic control valve 20 described later) by the biasing force of the spring 38, the first spool 34 is connected to the input port 26, the valve chamber 35, and the like. And the valve chamber 35 and the second drain port 32 are made to communicate with each other. When the first spool 34 is positioned at the left end against the urging force of the spring 38, the first spool 34 communicates between the input port 26 and the valve chamber 35, and The connection with the 2 drain port 32 is shut off.

  Further, a flow path 43 is formed in the housing 10, and the input port 26 communicates with the space where the pressure receiving surface 40 is disposed via the flow path 43. A portion of the flow path 43 on the input port 26 side is a flow path 45 having a diameter larger than that of the flow path 44 on the pressure receiving surface 40 side. A screw plug 46 is provided at a connection portion between the flow path 45 and the flow path 44. The threaded portion of the screw plug 46 is screwed into the small-diameter channel 44, and the head of the screw plug 46 is located in the large-diameter channel 45. For this reason, an annular gap 47 is formed between the outer peripheral surface of the head of the screw plug 46 and the inner peripheral surface of the flow path 45. In addition, a throttle channel 48 that connects the gap 47 and the channel 44 is formed inside the screw plug 46.

  The electromagnetic control valve 20 includes a valve seat body 41, a valve body 50, a connecting member 51, and a proportional solenoid 52.

  The valve seat body 41 is provided on the right side of the first spool 34 and is fixed to one end of the connecting member 51. A pilot chamber 53 is formed at the left end portion of the valve seat body 41. The left end surface of the valve seat body 41 and the right end surface of the first spool 34 can be brought into contact with and separated from each other, and the pilot chamber 53 of the valve seat body 41 and the pilot chamber 39 of the first spool 34 communicate with each other. A valve storage chamber 54 is formed inside the valve seat body 41. In the valve seat body 41, a drain channel 55 extending in the axial direction and a drain channel 56 extending in the radial direction are formed. The drain channel 55 allows the pilot chamber 53 and the valve storage chamber 54 to communicate with each other. The drain passage 56 passes through the valve storage chamber 54 and penetrates the valve seat body 41 in the radial direction. The drain channel 56 communicates the valve storage chamber 54 with the outer peripheral side of the valve seat body 41, and the outer peripheral side of the valve seat body 41 communicates with the first drain port 31. A valve seat surface 57 is formed on the inner wall surface on the left end of the valve storage chamber 54.

  The valve body 50 has a spherical shape, and is stored in the valve storage chamber 54 so as to be movable in the left-right direction.

  The connecting member 51 connects the valve seat body 41 and the proportional solenoid 52. A plunger 58 provided so as to be capable of moving back and forth in the axial direction (left-right direction) is inserted into the connecting member 51. The distal end of the plunger 58 is inserted into the valve storage chamber 54 so as to be movable in the axial direction, and is in contact with the valve body 50.

  The proportional solenoid 52 advances and retracts the plunger 58 in the axial direction when a command current is input from the electronic control unit 21.

  The hydraulic switch 200 includes a storage chamber S, an isolation cover 201, a flow rate detection valve 202, a fill detection unit 203, a pair of communication holes 204, and a pair of umbrella valves 205.

  The storage chamber S is provided inside the housing 10. The storage chamber S stores the flow rate detection valve 202. The storage room S has a first space S1 and a second space S2. The first space S1 and the second space S2 are isolated from each other by the isolation cover 201.

  The flow rate detection valve 202 is connected to the output circuit and is a valve for detecting the flow rate of oil sent to the output circuit. The flow rate detection valve 202 has a second spool 206 that slides in the left-right direction in accordance with the flow rate of oil passing therethrough. The second spool 206 is located on the left before completion of oil filling into the hydraulic chamber (hereinafter referred to as “fill completion”), and moves to the right when the fill is completed. The second spool 206 includes a spool body 206a and a first electric pin 206b.

  The second spool 206 divides the first space S1 of the storage chamber S into an oil chamber 61 and an oil chamber 62, and a portion of the second spool 206 that divides the oil chamber 61 and the oil chamber 62 An orifice 63 is formed. The oil chamber 62 communicates with the output port 27 via the flow path 64. The oil chamber 61 communicates with the valve chamber 35 via a flow path 65. When the pressure receiving areas in the left and right direction of the second spool 206 facing the oil chambers 61 and 62 are A1, A2, and A3, respectively, the pressure receiving area in the right direction (A1 + A3) and the pressure receiving area A2 in the left direction are “A1 + A3> A2 Is the relationship. For this reason, when the oil pressure in the oil chamber 61 and the oil chamber 62 become equal, and the force by which the second spool 206 is pushed rightward by the oil pressure in the oil chamber 61 becomes larger than the biasing force of the spring 75 described later, the second spool 206. Moves to the right.

  The second spool 206 has a protruding portion 66 protruding into the oil chamber 62 and a concave spring chamber 67 into which the spring 68 is inserted. The protrusion 66 is in contact with the end surface 69 a of the plug 69.

  The first electric pin 206 b is pressed against the cap member 71 fitted into the right end portion of the second spool 206 by the biasing force of the spring 68. The right end portion of the first electric pin 206b is inserted through the cap member 71.

  A spring 75 is provided between the cap member 71 and the cage member 72, and the cap member 71 is pressed to the left side by the biasing force of the spring 75.

  The fill detection unit 203 is provided on the right side of the flow rate detection valve 202. The fill detection unit 203 includes a second electric pin 73 and a fixing member 74. The second electric pin 73 is attached to the fixing member 74. The fixing member 74 is located on the right side of the cap member 71 and is attached to the outer surface of the housing 10. The second electric pin 73 is connected to the electronic control unit 21 via the electric circuit 80.

  The electric circuit 20 has a resistor R1 and a resistor R2. The resistor R1 and the resistor R2 are electrically connected in series. The second electric pin 73 is connected to a connection point a between the resistor R1 and the resistor R2. The electronic control unit 21 detects the fill completion by detecting a voltage change at the connection point a.

  The pair of communication holes 204 is provided on the inner wall of the storage chamber S. The pair of communication holes 204 communicate with the first space S1 and the second space S2. A pair of umbrella valves 205 is provided corresponding to each of the pair of communication holes 204. The configuration of the pair of communication holes 204 and the pair of umbrella valves 205 will be described later.

(Detailed configuration of hydraulic switch 200)
FIG. 2 is an enlarged view of FIG. FIG. 3 is a plan view from the direction of arrow A in FIG. FIG. 4 is a plan view from the direction of arrow B in FIG. FIG. 5 is a cross-sectional view taken along the line CC of FIG. 6 is a cross-sectional view taken along the line DD of FIG.

  As shown in FIG. 2, the hydraulic switch 200 includes a housing 10, a storage chamber S, an isolation cover 201, a second spool 206, a second electric pin 73, a pair of communication holes 204, and a pair of umbrella valves 205.

  The housing 10 constitutes the housing of the hydraulic control device 100 and the housing of the hydraulic switch 200.

  The storage chamber S has a first space S1 and a second space S2 that are isolated from each other by the isolation cover 201. The outer extension of the isolation cover 201 is in close contact with the inner wall of the storage chamber S. In this embodiment, the outer extension of the isolation cover 201 is joined to the cage member 72. The first electric pin 206b is inserted through substantially the center of the isolation cover 201. The isolation cover 201 is in close contact with the outer periphery of the first electric pin 206b.

  The isolation cover 201 is made of an elastic material. The isolation cover 201 is configured by, for example, a thin rubber sheet.

  The cage member 72 and the housing 10 are sealed with an elastic member 72a.

  The second spool 206 includes a spool body 206a and a first electric pin 206b. The spool body 206a is provided in the first space S1. The spool body 206a is slidable by the pressure of the oil filled in the oil chamber 62. The first electric pin 206b is attached to the right end of the spool body 206a. The first electric pin 206b is inserted through the isolation cover 201. Accordingly, the first electrical contact CP1 of the first electrical pin 206b is provided in the second space S2.

  The second electric pin 73 is provided on the right side of the first electric pin 206b. That is, the second electric pin 73 is provided in correspondence with the first electric pin 206b in the second space S2. The second electrical pin 73 has a second electrical contact CP2 that contacts the first electrical contact CP1.

  As shown in FIGS. 3 to 6, the pair of communication holes 204 includes a first communication hole 204 a and a second communication hole 204 b that communicate with the first space S <b> 1 and the second space S <b> 2, respectively. The pair of umbrella valves 205 includes a first umbrella valve 205a and a second umbrella valve 205b corresponding to the first communication hole 204a and the second communication hole 204b, respectively.

  The first communication hole 204a has a first space side opening OP11 provided on the first space S1 side and a second space side opening OP12 provided on the second space S2 side. The second communication hole 204b has a first space side opening OP21 provided on the first space S1 side and a second space side opening OP22 provided on the second space S2 side.

  The first umbrella valve 205a covers the first space side opening OP11 of the first communication hole 204a. Specifically, as shown in FIG. 5, the first umbrella valve 205a has an umbrella part 210a arranged in the first space S1. The umbrella part 210a is formed in a flange shape by an elastic member, and covers the first space side opening OP11. When air flows from the second space S2 to the first space S1, air is discharged from the first space side opening OP11 by turning up a part of the umbrella portion 210a.

  The second umbrella valve 205b covers the second space side opening OP22 of the second communication hole 204b. Specifically, as shown in FIG. 6, the second umbrella valve 205b has an umbrella part 210b arranged in the second space S2. The umbrella part 210b is formed in a flange shape by an elastic member, and covers the second space side opening OP22. When air flows from the first space S1 to the second space S2, a part of the umbrella portion 210b is turned up, so that air is discharged from the second space side opening OP22.

  Thus, air can freely enter and exit between the first space S1 and the second space S2. Therefore, even when the temperature of the storage space S rises, it is possible to suppress the normal movement of the second spool 206 from being hindered by the pressure difference between the first space S1 and the second space S2.

(Hydraulic control method)
Next, a hydraulic control method in the hydraulic control apparatus 100 will be described with reference to a time chart shown in FIG. In FIG. 7, the horizontal axis represents time (t). In addition, the vertical axis in FIG. 7A represents the command current (I) to the proportional solenoid 52. The vertical axis of FIG. 7B represents the pilot pressure (Pp) in the pilot chamber 39 of the pressure control valve 15. The vertical axis in FIG. 7C represents the pressure in the oil chamber 62, that is, the clutch pressure (P). The vertical axis in FIG. 7D represents the detection signal V from the fill detection unit 203.

1. Control at the time of clutch fill (t1-t2) When engaging the clutch, first, as shown in FIG. 7A, the electronic control unit 21 controls the command current I1 according to a predetermined large flow rate value at time t1. Is output to the proportional solenoid 52. This command current I1 is continued until time t2 when the completion of fill is detected (for example, about 0.1 second).

  As a result, the plunger 58 of the proportional solenoid 52 protrudes to the left side with a force corresponding to the magnitude of the command current I1, and presses the valve body 50 against the valve seat surface 57 at the tip. For this reason, the space between the drain flow paths 55 and 56 is narrowed, and the space between the pilot chamber 39 and the first drain port 31 is narrowed.

  Thus, the pilot pressure Pp in the pilot chamber 39 becomes a pilot pressure Pp1 corresponding to the magnitude of the command current I1 as shown in FIG. 7B. Then, the first spool 34 moves to the left to a position where the pilot pressure Pp1 and the biasing force of the spring 38 are balanced.

  In this state, the valve chamber 35 and the second drain port 32 are closed, and the valve chamber 35 and the input port 26 are communicated with each other. For this reason, the oil from the hydraulic pump flows into the oil chamber 61 via the input port 26 and the valve chamber 35, flows into the oil chamber 62 via the orifice 63, and further flows through the flow path 64 and the output port 27. Flows into the hydraulic chamber via As a result, the supply of oil to the hydraulic chamber is started, and a large amount of oil corresponding to the magnitude of the command current I1 flows in for a short time (between time t1 and time t2).

  At this time, when the oil flows in through the orifice 63, a differential pressure ΔP is generated between the oil chamber 61, the oil chamber 62, and the oil pressure. Due to the relationship between the differential pressure ΔP and the areas A1, A2, and A3 of the second spool 206 described above, a leftward force is applied to the second spool 206, and the protrusion 66 of the second spool 206 is moved to the oil chamber 62. It contacts the end surface 69a of the inner plug 69. For this reason, the 1st electric pin 206b and the 2nd electric pin 73 will be in a non-contact state, and the detection signal from the fill detection part 203 is maintained by Voff, as shown in FIG.7 (d). Thereby, the electronic control unit 21 determines that the filling is not completed. The electronic control unit 21 maintains the command current to the proportional solenoid 52 at the command current I1 until the completion of fill is detected.

2. When clutch fill is completed (t2)
When the hydraulic chamber is filled with oil, the flow of oil passing through the orifice 63 stops, so that the differential pressure ΔP between the oil chamber 61 and the oil chamber 62 is eliminated. In this case, the second spool 206 moves to the right due to the relationship between the pressure receiving areas A1, A2, and A3 of the second spool 206. At this time, the second spool 206 pushes the cap member 71 to the right against the biasing force of the spring 75 by the pressure Ps in the oil chamber 61, and brings the first electric pin 206 b into contact with the second electric pin 73. Then, the detection signal from the fill detection unit 203 changes to Von as shown in FIG. As a result, the electronic control unit 21 determines that the fill is complete. Note that until the fill completes because even enhance the pilot pressure P _P pressure of the oil chamber 62 is not increased, the clutch pressure P changes as shown in FIG. 7 (c).

3. Control at Clutch Pressure Adjustment (t2-t3) When the electronic control unit 21 determines that the fill is completed at time t2, the command current I corresponds to the initial pressure Ps of the clutch pressure P as shown in FIG. The initial command current I2 is set and output. At this time, as shown in FIG. 7B, the pilot pressure Pp in the pilot chamber 39 becomes the pilot pressure Pp2 corresponding to the initial command current I2.

  Thereafter, as shown in FIG. 7A, the electronic control unit 21 gradually increases the command current I within a predetermined time from the initial command current I2 to the set command current I3 corresponding to the predetermined set clutch pressure Pe. Apply hydraulic modulation. Thereby, the pressing force of the valve body 50 by the plunger 58 of the proportional solenoid 52 gradually increases according to the magnitude of the command current I. As the pressing force of the valve body 50 increases, the gap between the valve seat surface 57 and the valve body 50 gradually decreases. For this reason, as shown in FIG. 7B, the pilot pressure Pp in the pilot chambers 39 and 53 gradually increases from Pp2 to Pp3 according to the magnitude of the command current I. Thereby, the opening degree of the pressure control valve 15 is changed. Further, the clutch pressure P gradually increases according to the magnitude of the command current I, and reaches the set clutch pressure Pe at a time point t3 after a predetermined time.

  Then, the output of the command current I3 is continued so as to maintain the set clutch pressure Pe until the clutch is disengaged at time t4. At this time, the second spool 206 moves to the right against the spring 75 by the pressure of the oil chamber 61. For this reason, the first electric pin 206b and the second electric pin 73 are kept in contact with each other, and the fill detection unit 203 continues to output the detection signal Von indicating the completion of the fill.

(Function and effect)
(1) The electrical contact protection structure of the hydraulic control apparatus 100 according to the present embodiment includes a storage chamber S, a second spool 206, a second electrical pin 73, and a pair of communication holes 204. The storage chamber S has a first space S1 and a second space S2 that are isolated by the isolation cover 201. The second spool 206 includes a spool body 206a provided in the first space S1, and a first electric pin 206b attached to the spool body 206a and inserted through the isolation cover 201. The second electric pin 73 is provided in the second space S2. The pair of communication holes 204 communicate with the first space S1 and the second space S2.

  Thus, since 1st space S1 and 2nd space S2 are isolated by the isolation | separation cover 201, it can suppress that oil penetrate | invades from 1st space S1 to 2nd space S2. Therefore, it is possible to suppress oil from adhering to the first electric contact CP1 of the first electric pin 206b and the second electric contact CP2 of the second electric pin 73. Therefore, the electrical connectivity between the first electric pin 206b and the second electric pin 73 can be maintained, and the completion of filling can be detected with high accuracy.

  Further, air can be circulated between the first space S1 and the second space S2 via the pair of communication holes 204. For this reason, even when the second spool 206 slides or when the temperature of the storage space S changes, the pressures in the first space S1 and the second space S2 can be made the same. Therefore, smooth sliding of the second spool 206 can be maintained.

(2) The electrical contact protection structure of the hydraulic control device 100 according to the present embodiment includes the first umbrella valve 205a that covers the first space side opening OP11 of the first communication hole 204a and the second space side of the second communication hole 204b. And a second umbrella valve 205b covering the opening OP22.

  Therefore, when air flows from the first space S1 to the second space S2, oil can be prevented from entering the second space S2 through the first communication hole 204a and the second communication hole 204b. Therefore, it can suppress more that oil adheres to 1st electrical contact CP1 and 2nd electrical contact CP2.

(Other embodiments)
Although the present invention has been described according to the above-described embodiments, it should not be understood that the descriptions and drawings constituting a part of this disclosure limit the present invention. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art.

(1) In the above embodiment, the hydraulic switch 200 has the pair of communication holes 204 and the pair of umbrella valves 205, but is not limited thereto. As shown in FIG. 8, the hydraulic switch 200 may have only one communication hole 204c. Even in this case, air can be circulated between the first space S1 and the second space S2 through the single communication hole 204c. Further, as shown in FIG. 9, the communication hole 204c preferably has a labyrinth structure. The labyrinth structure is a bent structure. Thereby, it can suppress more that oil penetrate | invades into 2nd space S2 via the communicating hole 204c. In addition, as a labyrinth structure which the communication hole 204c has, not only the structure shown in FIG. 9 but a well-known labyrinth structure is employable.

(2) In the embodiment described above, the hydraulic switch 200 has the cage member 72 that constitutes a part of the inner wall of the storage chamber S, but is not limited thereto. The hydraulic switch 200 may not have the cage member 72. In this case, the outer extension of the isolation cover 201 is in direct contact with the housing 10.

(3) In the above embodiment, the casing 10 constitutes the casing of each of the hydraulic control device 100 and the hydraulic switch 200, but is not limited thereto. The hydraulic switch 200 may have a housing other than the housing 10.

(4) In the above embodiment, the clutch has been described as an example of the friction engagement device, but the present invention is not limited to this. The friction engagement device may be, for example, a brake.

  As described above, the present invention naturally includes various embodiments not described herein. Therefore, the technical scope of the present invention is defined only by the invention specifying matters according to the scope of claims reasonable from the above description.

DESCRIPTION OF SYMBOLS 10 ... Housing 72 ... Cage member 73 ... 2nd electric pin 201 ... Isolation cover 204 ... Communication hole 205 ... Umbrella valve 206 ... 2nd spool 206a ... Spool main-body part 206b ... 1st electric pin S ... Storage chamber S1 ... 1st Space S2 ... 2nd space

Claims (3)

A housing,
A storage chamber provided in the housing;
A cage member disposed in the accommodation chamber;
An isolation cover joined to the cage member and separating the storage chamber into a first space and a second space;
A spool provided in the first space and slidable by hydraulic pressure, and a first electric pin attached to the spool body and inserted through the isolation cover;
A second electrical pin provided in the second space and corresponding to the first electrical pin;
A communication hole provided in the cage member and communicating with the first space and the second space;
An electrical contact protection structure for a hydraulic control device. The communication hole is composed of a first communication hole and a second communication hole,
A first umbrella valve that covers the first space side opening of the first communication hole;
A second umbrella valve that covers the second space side opening of the second communication hole;
The electrical contact protection structure for a hydraulic control device according to claim 1, further comprising: The communication hole has a labyrinth structure.
The electrical contact protection structure for a hydraulic control device according to claim 1 or 2.

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