CN109154407B

CN109154407B - Valve device

Info

Publication number: CN109154407B
Application number: CN201780031320.5A
Authority: CN
Inventors: 石黑元康; 北见雄希; 田边珠实; 中川大树
Original assignee: Saginomiya Seisakusho Inc
Current assignee: Saginomiya Seisakusho Inc
Priority date: 2016-06-15
Filing date: 2017-05-23
Publication date: 2020-02-14
Anticipated expiration: 2037-05-23
Also published as: JP6475197B2; JP2017223293A; WO2017217193A1; CN109154407A

Abstract

In a pressure-balanced electric valve, a sealing section (4) is formed of a pair of leaf springs (41, 41), a pair of L-shaped gaskets (45, 45), and a reinforcing plate (46), the leaf spring (41) is formed of an annular base plate section (41a) and 12 blade sections (41b), a first curved section (41b1) and an outer second curved section (41b2) are formed in the blade section (41b), an end point (P, P) of a second curved section (41b2) is made to be substantially equal to an inner surface of an edge section (45b) of the L-shaped gasket (45), a width [ α 1'] of a gap section (41c) and a width [ β 1] of the blade section (41b) are made to be [ α 1' ] [ β 1] < ] and 24 apexes formed by a P end point of an edge of the second blade section (41b2) are made to be in contact with the inner surface of the edge section (45b) uniformly.

Description

Valve device

Technical Field

The present invention relates to a valve device used in a refrigeration cycle or the like, and more particularly, to a valve device including: a moving member having a valve that moves along the guide portion to control a flow of the fluid; and a sealing part which is provided on the moving component and is embedded in the guide part.

Background

Conventionally, as such valve devices, there are valve devices disclosed in, for example, japanese patent laid-open nos. 2000-320711 (patent document 1), 2012-229886 (patent document 2), and 2015-25507 (patent document 3).

The valve device of patent document 1 is a control valve for controlling the flow rate of a fluid in two directions during a refrigeration cycle, and includes a cylindrical fixed sleeve member (guide portion) provided with a movable sleeve member (moving member), and a valve port is opened and closed by a valve main body provided in the movable sleeve member. Further, the seal portion formed of the packing and the spring provided in the movable sleeve member prevents leakage of the pressure fluid between the back pressure chamber for pressure balance and the valve chamber.

The valve device of patent document 2 is a temperature expansion valve that performs superheat degree control by changing the opening degree of a valve port in a refrigeration cycle based on the temperature of an outlet-side pipe of an evaporator and the evaporation pressure of a refrigerant. A valve body (moving member) for opening and closing the valve port is disposed in a guide hole of the valve housing, and a seal member for sealing between a pressure equalizing chamber for introducing an evaporation pressure into the guide hole and the first port is provided in the valve body. The sealing member is composed of a gasket and a leaf spring.

The valve device of patent document 3 is a four-way switching valve (flow path switching valve) that switches the flow direction of a refrigerant in a refrigeration cycle, and a piston valve (moving member) that is movable in a cylindrical valve housing includes a valve body (valve) facing a valve seat, and switches the flow path by applying a differential pressure of the refrigerant to the piston valve to move the piston valve. The piston of the piston valve is composed of a packing, a tooth spring (leaf spring), and the like, which are in sliding contact with the inner periphery of the valve housing.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. 2000-320711

Patent document 2: japanese patent laid-open No. 2012 and 229886

Patent document 3: japanese patent laid-open publication No. 2015-25507

Disclosure of Invention

Problems to be solved by the invention

The above-described conventional valve devices are all configured such that a moving member including a valve moves in a cylindrical guide portion, and a fluid differential pressure in a space provided on both sides of a seal portion of the moving member acts on the moving member. The seal portion is in sliding contact with the inner peripheral surface of the guide portion. Therefore, in such a valve device, it is necessary to ensure the sealing performance of the seal portion and to set the sliding resistance of the seal portion with respect to the guide portion to such an extent that the sliding resistance does not hinder the operation of the moving member.

Further, patent document 2 discloses a plate spring having a radially extending convex tooth-shaped portion, and an edge portion of a pad is pressed against an inner peripheral surface of a guide hole by an elastic force of the convex tooth-shaped portion. However, in the leaf spring of patent document 2, the width of the convex tooth-shaped portions is smaller than the width of the gaps between the convex tooth-shaped portions, and therefore it is difficult to apply a sufficient elastic force to the edge portions of the gasket, and there is room for improvement in sealing performance. Further, if the pressing force of the leaf spring is too strong, the sliding resistance of the pad against the guide hole may become large, and the pad may not be able to operate.

The object of the present invention is to optimize the sealing performance and sliding resistance of a sealing part relative to a guide part in a valve device having a moving member having a valve that moves along the guide part to control the flow of a fluid, and the sealing part provided in the moving member and fitted in the guide part.

Means for solving the problems

The valve device according to claim 1 includes: a cylindrical guide portion; a moving member having a valve that moves along an axis of the guide portion to control a flow of the fluid; and a seal portion that is provided in the moving member and fitted into the guide portion, and that causes a differential pressure of the fluid in spaces on both sides of the seal portion in the guide portion in the axial direction to act on the moving member, the valve device being characterized in that the seal portion includes: an L-shaped pad including an edge portion in sliding contact with an inner peripheral surface of the guide portion and a base portion held by the moving member; and a leaf spring that is disposed inside the L-shaped pad and presses the edge portion toward an inner circumferential surface side of the guide portion, wherein the leaf spring is configured from a base plate portion held by the moving member, and a plurality of blade portions radially formed on an outer circumference of the base plate portion and pressing the edge portion of the L-shaped pad from inside, and has a first bent portion at a boundary portion between the blade portions and the base plate portion, and a second bent portion outside the first bent portion and abutting the edge portion, the blade portions are 12 to 20, and have a width larger than a width of a gap portion between the blade portions, and the edge portion of the L-shaped pad is pressed by a vertex of a 2 n-sided polygon formed by end points of the second bent portions of the n blade portions.

The valve device according to claim 2, wherein the width α' of the gap portion and the width β of the blade portion have the following relationship:

α′≤β≤2.1·α′。

the valve device according to claim 3 is the valve device according to

claim

1 or 2, wherein the first curved portion is formed in a linear portion of a side portion of the blade portion.

The valve device according to claim 4 is the valve device according to any one of claims 1 to 3, wherein a lower portion of the gap portion between the root portions of the blade portions is an arc portion.

The valve device according to claim 5 is the valve device according to any one of claims 1 to 4, wherein the number of the blade portions is an odd number.

The valve device according to claim 6 is the valve device according to any one of claims 1 to 5, wherein the moving member is constituted by a valve body and a coupling portion, and the base portion of the L-shaped gasket and the base plate portion of the plate spring are sandwiched between the valve body and the coupling portion, so that the seal portion is sandwiched between the moving member and the base plate portion.

The valve device according to claim 7 is the valve device according to any one of claims 1 to 6, wherein the seal portion includes a pair of the plate springs, a pair of the L-shaped gaskets, and a reinforcing plate interposed between the pair of the L-shaped gaskets, the pair of the L-shaped gaskets are disposed such that the pair of edge portions face outward in the axial direction, the reinforcing plate is sandwiched between the pair of base portions, and the seal portion is sandwiched between the moving member.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the valve device of

claim

1 or 2, the leaf spring presses the edge portion of the L-shaped gasket at the apex of the 2 n-sided polygon by the n blade portions, each end point of the second bend portion and the inner surface of the edge portion of the L-shaped gasket are pressing points that are substantially evenly present on the circumference, the width of the blade portion is larger than the width of the gap portion, and the number of the blade portions is 12 to 20, so that the width β of the blade portion is secured, and sufficient pressing force can be obtained with respect to the edge portion, thereby securing sealing performance.

According to the valve device of claim 3, in addition to the effects of

claim

1 or 2, the blade portions are not subjected to stress such as torsion even if resistance is received from the L-pad when the seal portion slides, and therefore durability can be maintained even if sliding is repeated.

According to the valve device of claim 4, in addition to the effect of any one of claims 1 to 3, since the lower portion of the gap portion is formed into the arc portion, no crack or the like is generated from the gap portion, and the strength of the plate spring can be secured.

According to the valve device of claim 5, in addition to the effects of any one of claims 1 to 4, since the number of the blade sections is an odd number, a three-point support structure in which the positions where the blade sections abut and the positions where the blade sections do not abut are asymmetrical with respect to the axis is obtained, and the seal section is less likely to be inclined in the guide section, and uniform sealing is possible.

According to the valve device of claim 6, in addition to the effect of any one of claims 1 to 5, since the seal portion is sandwiched between the valve body and the connecting portion, the seal portion can be held by the moving member with a simple structure.

According to the valve device of claim 7, in addition to the effect of any one of claims 1 to 6, the gap between the inner peripheral surface of the guide portion and the outer peripheral surface of the valve member can be reliably sealed by the pair of L-shaped gaskets of the seal portion.

Drawings

Fig. 1 is a longitudinal sectional view showing a closed state of an electrically operated valve as a valve device according to an embodiment of the present invention.

Fig. 2 is an enlarged view of a main portion of fig. 1.

Fig. 3 is a plan view of the plate spring of the first example in the embodiment in an expanded state.

Fig. 4 is a plan view and a sectional view of an assembled state of the plate spring and the L-pad of the first embodiment.

Fig. 5 is a plan view of a plate spring in an expanded state according to a second example of the embodiment.

Fig. 6 is a plan view and a sectional view of an assembled state of the plate spring and the L-pad of the second embodiment.

Fig. 7 is a plan view of a plate spring in a developed state according to a third example of the embodiment.

Fig. 8 is a plan view and a sectional view of an assembled state of the plate spring and the L-pad of the third embodiment.

Fig. 9 is a view illustrating a first curved portion and a circular arc portion of the plate spring of the first to third embodiments.

Detailed Description

Hereinafter, embodiments of the valve device according to the present invention will be described with reference to the drawings. Fig. 1 is a longitudinal sectional view showing a closed state of an electrically operated valve of a valve device according to an embodiment, and fig. 2 is an enlarged view of a main portion of fig. 1. Note that the concept of "top and bottom" in the following description corresponds to the top and bottom in the drawing of fig. 1. The motor-operated valve of this embodiment has a substantially cylindrical valve housing 1, and a valve chamber 1A is formed in the valve housing 1. Further, a joint pipe 11 communicating with the valve chamber 1A from the side surface is attached to the valve housing 1, and a valve seat member 13 is attached to the lower end portion. A circular valve port 13a is formed in the center of the valve seat member 13, and a mortar-shaped seating surface 13b is formed around the opening of the valve port 13 a. Further, a joint pipe 12 is attached to the valve seat member 13 along the axis X direction of the valve chamber 1A so as to communicate with the valve port 13 a.

A hollow multistage cylindrical valve guide member 2 inserted from the upper end of the valve housing 1 is disposed in the valve chamber 1A. The valve guide member 2 is integrally formed with: a small-diameter cylindrical guide portion 21 located on the valve port 13a side with the axis X as a center axis; a middle diameter cylindrical portion 22 having a larger diameter than the guide portion 21; and a large-diameter mounting portion 23 fitted into the upper end of the valve housing 1. A piston-shaped valve member 3 as a "moving member" is disposed in the guide portion 21 so as to be movable in the axis X direction. Further, a part of the valve member 3 is accommodated in the valve guide member 2, thereby partitioning the inner space of the valve guide member 2 and forming a back pressure chamber 2A with respect to the valve member 3 in the valve guide member 2.

The valve member 3 is formed in a substantially cylindrical shape as a whole, and the valve member 3 includes a substantially cylindrical valve body 3A as a "valve" and a connection portion 3B connected to a stepping motor 7 described later. The valve body 3A has a columnar portion 31 having a columnar shape facing the seating surface 13b, and a boss portion 32 having a diameter smaller than that of the columnar portion 31. A coupling hole 3A is formed in the center of the valve body 3A. The coupling portion 3B includes a coupling shaft 33 fitted into the coupling hole 3A of the valve body 3A, and a boss portion 34 having the same diameter as the boss portion 32 and having a substantially cylindrical shape. The valve body 3A and the coupling portion 3B are fastened in a state where a seal portion 4 described later is sandwiched between the boss portion 32 and the boss portion 34. That is, the coupling shaft 33 of the coupling portion 3B is fitted into the coupling hole 3A of the valve body 3A, and the lower end of the coupling shaft 33 and the lower end of the columnar portion 31 are welded to each other, thereby fastening them to each other. The coupling portion 3B includes: a pressure equalizing path 3b extending upward from the valve port 13a side at the center of the connecting shaft 33; and a pressure equalizing passage 3c connected to the vertical pressure equalizing passage 3b and opening into the back pressure chamber 2A. The

pressure equalizing passages

3b and 3c communicate the valve port 13a with the back pressure chamber 2A.

A support member 5 is fastened to the upper portion of the valve guide member 2 by a flange metal fitting 51, and an insertion hole 52 is formed in the support member 5 in the axis X direction, and a through hole 53 for conducting the insertion hole 52 to the inside of a housing 72 described later is formed. A cylindrical valve frame 6 is inserted into the insertion hole 52 so as to be movable in the axis X direction, and the valve member 3 is fastened to a lower end of the valve frame 6. The valve frame 6 is engaged with a rotor shaft 71 of a stepping motor 7 described later. That is, the flange portion 71a at the lower end of the rotor shaft 71 sandwiches the washer 62 together with the holding portion 61 at the upper end of the valve frame 6, and the valve frame 6 is rotatably engaged with the lower end of the rotor shaft 71. Thereby, the valve frame 6 and the valve member 3 are supported in a state of being rotatably suspended by the rotor shaft 71. Further, a compression coil spring 64 is disposed between the spring holder 63 and the boss portion 34 of the coupling portion 3B in the valve frame 6. The rotor shaft 71 is provided with a male screw portion 71b, and the male screw portion 71b is screwed to a female screw portion 5a formed in the support member 5. Thereby, the rotor shaft 71 moves in the axis X direction as it rotates.

A stepping motor 7 is mounted on the upper portion of the valve housing 1. The stepping motor 7 is constituted by the rotor shaft 71, the housing 72, the magnetic rotor 73, and the stator coil 74. A magnetic rotor 73 having an outer peripheral portion magnetized in multiple poles is rotatably provided in the housing 72, and the rotor shaft 71 is fastened to the magnetic rotor 73. Further, a rotation restricting mechanism 8 that restricts rotation of the magnetic rotor 73 in conjunction with the projection 73a of the magnetic rotor 73 is provided on the top surface portion of the housing 72. Further, a stator coil 74 is disposed on the outer periphery of the housing 72, and the stepping motor 7 rotates the magnetic rotor 73 in accordance with the number of pulses by applying a pulse signal to the stator coil 74.

According to the above configuration, the magnetic rotor 73 and the rotor shaft 71 are rotated by the driving of the stepping motor 7, and the rotor shaft 71 is moved in the axis X direction by the screw feeding mechanism of the male screw portion 71b of the rotor shaft 71 and the female screw portion 5a of the support member 5. Thereby, the valve member 3 moves in the axis X direction, the valve member 3 is guided by the guide portion 21 of the valve guide member 2, and the valve member 3 is unseated and seated on the seating surface 13 b. This opens and closes the valve port 13 a. The opening degree of the valve port 13a is controlled in accordance with the position (lift amount) of the valve member 3 in the axis X direction, thereby controlling the flow rate of the fluid flowing through the valve port 13 a. Thus, when the valve member 3 is guided by the guide portion 21, the seal portion 4 slides along the guide surface 21a of the guide portion 21.

The electric valve of this embodiment is used for controlling two flows, i.e., a first flow (a flow indicated by a solid arrow in fig. 1) in which a fluid (refrigerant) flows into the joint pipe 11 and flows out of the joint pipe 12, and a second flow (a flow indicated by a broken arrow in fig. 1) in which a fluid flows into the joint pipe 12 and flows out of the joint pipe 11. The pressure of the valve chamber 1A communicating with the joint pipe 11 is introduced into the space below the seal portion 4 in the guide portion 21 through the gap between the cylindrical portion 31 of the valve member 3 and the guide portion 21. Further, the pressure of the valve port 13a communicating with the joint pipe 12 is introduced into the back pressure chamber 2A (the upper space of the seal portion 4) via the

pressure equalizing passages

3b and 3c of the valve member 3. The seal portion 4 seals a space below the seal portion 4 and the back pressure chamber 2A.

In the first flow, the low pressure at the valve port 13a is introduced into the back pressure chamber 2A through the

pressure equalizing passages

3b and 3 c. In the second flow, the high pressure on the valve port 13a side is introduced into the back pressure chamber 2A through the

pressure equalizing passages

3b and 3 c. Therefore, the same pressure acts on the valve member 3 from both sides of the valve port 13a and the back pressure chamber 2A. Accordingly, the force generated by the differential pressure between the high pressure and the low pressure of the fluid is cancelled with respect to the valve member 3 in the direction of the axis X, and the pressure balance is maintained.

In this way, the motor-operated valve of the embodiment includes: a cylindrical guide portion 21; a valve member 3 (moving member) that moves along the axis X of the guide portion 21; and a seal portion 4 provided in the valve member 3 and fitted in the guide portion 21. The cylindrical portion 31 (valve) of the valve member 3 controls the flow rate of the fluid, i.e., the flow of the fluid, by controlling the opening degree of the valve port 13 a. The electrically operated valve is a valve device in which a differential pressure of fluid in spaces on both sides of the sealing portion 4 in the axial direction X in the guide portion 21 is applied to the valve member 3.

As shown in fig. 2, the seal portion 4 includes: a pair of

leaf springs

41, 41 of the first embodiment formed of a thin metal plate; a pair of L-shaped

gaskets

45, 45 made of fluororesin such as PTFE or PFA; and an annular reinforcing plate 46 made of a metal plate. Further, the

leaf springs

41, 41 are fitted inside the L-shaped

spacers

45, 45 by sandwiching the reinforcing plate 46 between the L-shaped

spacers

45, 45. The leaf spring 41, the L-shaped gasket 45, and the reinforcing plate 46 each have an opening at the center, the coupling shaft 33 of the coupling portion 3B penetrates through the opening, and the

leaf springs

41 and 41 are pressed by the boss 32 on the valve element 3A side and the boss 34 on the coupling portion 3B side of the valve member 3, whereby the seal portion 4 is attached to the valve member 3.

The L-shaped spacer 45 is formed by cutting, and includes an annular base portion 45a and an edge portion 45b provided upright from the outer periphery of the base portion 45a in a direction (axis X direction) substantially perpendicular to the base portion 45 a. The edge portion 45b is a portion that is pressed by the guide surface 21a of the guide portion 21 and slidably contacts therewith, and seals between the seal portion 4 and the guide surface 21 a. The base portion 45a is a portion sandwiched between the plate spring 41 and the reinforcing plate 46 (and the boss 32 or the boss 34).

The plate spring 41 is formed by press working of a metal plate such as SUS, and includes a substantially annular base plate portion 41a and a blade portion 41b that is erected in a direction (axial direction X) substantially perpendicular to the base plate portion 41a from an outer circumferential direction of the base plate portion 41 a. The blade 41b is a portion that presses the edge 45b of the L pad 45 from inside. The substrate portion 41a is a portion sandwiched between the base portion 45a of the L-shaped spacer 45 and the boss 32 or the boss 34.

Fig. 3 is a plan view of the plate spring 41 of the first embodiment in an expanded state, fig. 4 is a plan view and a partial sectional view showing an assembled state of the plate spring 41 and the L-spacer 45 of the first embodiment, and fig. 4(B) is a section a-a in fig. 4 (a). As shown in the figure, the plate spring 41 has 12 leaf portions 41b on the outer periphery of the base plate portion 41 a. The vane portions 41b are radially formed on the outer periphery of the

substrate portion

41a, and 12 gap portions 41c are provided between the

adjacent vane portions

41b, 41 b. The first bent portion 41b1 at the boundary between the blade portion 41b and the base plate portion 41a and the second bent portion 41b2 outside the first bent portion 41b1 are formed by bending the blade portion 41b at the first bending line and the second bending line shown in fig. 3. Fig. 3 shows the expanded state, and the first curved portion 41b1 and the second curved portion 41b2 are shown by thick solid lines.

In the assembled state of the plate spring 41 shown in fig. 4, the portion of the first bent portion 41b1 is further bent from the state before assembly, and the plate spring 41 is assembled in the L-shaped spacer 45 against the elastic restoring force of the plate spring 41. As shown in fig. 4(a), the end points P, P of both side ends of the second bent portion 41b2 abut against the inner surface of the edge portion 45b of the L pad 45. The first bent portion 41b1 is located on the base portion 45a on the inner side (on the axis X side) of the edge portion 45b of the L pad 45.

Here, as shown in fig. 3, the distance of the end points P, P of the two adjacent second bent portions 41b2, 41b2 in the gap portion 41c is set to "the width of the gap portion 41 c", and the length of the second bent portion 41b2 is set to "the width of the blade portion 41 b"

α1＝0.77mm、

β1＝1.15mm＝1.5·α1，

And has the following relationship:

α1≤β1≤1.5·α1。

that is, the width [ β 1] of the blade portion 41b and the width [ α 1] of the gap portion 41c are approximately the same, and the blade portion 41b is bent at the first bent portion 41b1, so that the width of the gap portion 41c is [ α 1' ] slightly smaller than [ α 1] in the state of fig. 4, and of course [ β 1] is not changed.

Even in this bent state, the width [ α 1' ] of the gap portion 41c and the width [ β 1] of the blade portion 41b are substantially the same, and in the first embodiment,

α1′＝0.58mm、

β1＝1.15mm＝1.98·α1′，

and has the following relationship:

α1′≤β1≤2.1·α1′。

the end points P of the second bent portions 41b2 are 24 vertices of a 24-sided polygon, and abut against the inner surface of the edge portion 45b of the L-shaped pad 45. Thus, the 12-piece blade portion 41b presses the edge portion 45b from the inside to the outside in the radial direction substantially uniformly. That is, the plate spring 41 presses the edge portions 45b at 24 points at substantially uniform positions around the circumference.

Fig. 5 is a plan view of the plate spring 42 of the second embodiment in an expanded state, fig. 6 is a plan view and a partial sectional view showing an assembled state of the plate spring 42 and the L-spacer 45 of the second embodiment, and fig. 6(B) is a section a-a in fig. 6 (a). Further, the leaf spring 42 of the following second embodiment and the leaf spring 43 of the third embodiment are different from the leaf spring 41 of the first embodiment in the number of blade portions and the width of the blade portions (the length of the second bent portion), and other configurations are common to the first to third embodiments. For example, the position (radius from the center) of the first folding line is the same in the first to third embodiments.

The leaf spring 42 of the second embodiment has 15 leaf portions 42b on the outer periphery of the base plate portion 42 a. The blade portions 42b are radially formed on the outer periphery of the base plate portion 42a, and 15 gap portions 42c are provided between the

blade portions

42b and 42b adjacent to each other. Then, by bending the blade portions 42B at the first bend line and the second bend line shown in fig. 5, as shown in fig. 6(B), the first bent portions 42B1 at the boundary portions between the blade portions 42B and the base plate portion 42a and the second bent portions 42B2 outside the first bent portions 42B1 are formed. Further, the leaf spring 42 is assembled in the L-shaped pad 45, and as shown in fig. 6(a), the end points P, P of both side ends of the second bent portion 42b2 abut against the inner surface of the edge portion 45b of the L-shaped pad 45. The first curved portion 42b1 is located on the base portion 45a on the inner side (on the axis X side) of the edge portion 45b of the L pad 45.

In the leaf spring 42 of the second embodiment, as shown in fig. 5, the width [ α 2] of the gap portion 42c and the width [ β 2] of the blade portion 42b (the length of the second bent portion 42b 2) are set to be

α2＝0.76mm、

β2＝0.93mm＝1.22·α2，

And has the following relationship:

α2≤β2≤1.5·α2。

that is, the blade portion 42b has a width of substantially [ β 2] and the gap portion 42c has a width of substantially [ α 2], and the width of the blade portion 42b and the width of the gap portion 42c are substantially the same, and the blade portion 42b is bent at the first bent portion 42b1, so that the width of the gap portion 42c is [ α 2' ] slightly smaller than [ α 2] in the state of fig. 6.

Even in this bent state, the width [ α 2' ] of the gap portion 42c and the width [ β 2] of the blade portion 42b are substantially the same, and in this second embodiment,

α2′＝0.45mm、

β2＝0.93mm＝2.07·α2′，

and has the following relationship:

α2′≤β2≤2.1·α2′。

the end point P of each second bent portion 42b2 is formed by 30 vertices of a 30-sided polygon and abuts against the inner surface of the edge portion 45b of the L-shaped pad 45. Thereby, the 15 blade portions 42b press the edge portion 45b from the inside to the outside in the radial direction substantially uniformly. That is, the plate spring 42 presses the edge portions 45b at a plurality of points of 30 at substantially uniform positions around the circumference.

Fig. 7 is a plan view of the plate spring 43 of the third embodiment in an expanded state, fig. 8 is a plan view and a partial sectional view showing an assembled state of the plate spring 43 and the L-spacer 45 of the third embodiment, and fig. 8(B) is a section a-a in fig. 8 (a).

The leaf spring 43 of the third embodiment has 20 leaf portions 43b on the outer periphery of the base plate portion 43 a. The vane portions 43b are radially formed on the outer periphery of the base plate portion 43a, and 20 gap portions 43c are provided between the

adjacent vane portions

43b, 43 b. Then, by bending the blade portions 43B at the first bending line and the second bending line shown in fig. 7, as shown in fig. 8(B), the first bent portions 43B1 at the boundary portions between the blade portions 43B and the base plate portion 43a and the second bent portions 43B2 outside the first bent portions 43B1 are formed. Further, the leaf spring 43 is assembled in the L-shaped pad 45, and as shown in fig. 8(a), the end points P, P of both side ends of the second bent portion 43b2 abut against the inner surface of the edge portion 45b of the L-shaped pad 45. The first curved portion 43b1 is located on the base portion 45a on the inner side (on the axis X side) of the edge portion 45b of the L pad 45.

In the leaf spring 43 of the third embodiment, as shown in fig. 7, the width [ α 3] of the gap portion 43c and the width [ β 3] of the blade portion 43b (the length of the second bent portion 43b 2) are set to be equal to

α3＝0.51mm、

β3＝0.63mm＝1.24·α3，

And has the following relationship:

α3≤β3≤1.5·α3。

that is, the blade portion 43b has a width of substantially [ β 3] and the gap portion 43c has a width of substantially [ α 3], and the width of the blade portion 43b and the width of the gap portion 43c are substantially the same, and the blade portion 43b is bent at the first bent portion 43b1, so that the width of the gap portion 43c is slightly smaller than [ α 3' ] than [ α 3] in the state of fig. 8.

Even in this bent state, the width [ α 3' ] of the gap portion 43c and the width [ β 3] of the blade portion 43b are substantially the same, and in this third embodiment,

α3′＝0.40mm、

β3＝0.63mm＝1.58·α3′，

and has the following relationship:

α3′≤β3≤2.1·α3′。

the end points P of the second curved portions 43b2 form 40 vertices of a 40-sided polygon and abut against the inner surface of the edge portion 45b of the L-shaped pad 45. Thus, the 20-piece blade portions 43b press the edge portion 45b from the inside to the outside in the radial direction substantially uniformly. That is, the plate spring 43 presses the edge portions 45b at 40 points at substantially uniform positions around the circumference.

Hereinafter, the [ β 1, β 2, β 3] of each example is represented as [ β ] and the [ β 01 ', α 2', α 3 '] is represented as [ α' ], the

leaf springs

41, 42, 43 of each example are configured such that the

n leaf portions

41b, 42b, 43 press the edge portion 45b of the L pad 45 at the apex of the 2 n-gon, that is, the end points P, P of the second bent portions 41b2, 42b2, 43b2 are pressed points on the circumference with respect to the inner surface of the edge portion 45b of the L pad 45, and the pressed points are located at substantially equal positions on the circumference by being α '≦ β ≦ 2.1 · α', and thus, sealability is ensured, that is, if the interval (the length of the sides of the polygon) of the end points P, P is extremely large, there is a possibility that the edge portion 45b floats from the guide surface 21a at the center position of the end point P, P and leaks.

In each of the embodiments, the width [ β ] of the blade portion is β > α 'with respect to the width [ α' ] of the gap portion, that is, the width of the

blade portions

41b, 42b, 43b is wider than the width of the

gap portions

41c, 42c, 43c, and thus, α is equal to or less than β, and the width [ β ] of the blade portion is ensured by setting the number of the blade portions to 12 to 20, and a sufficient pressing force (elastic force) can be obtained with respect to the edge portion 45b, and sealing performance can be ensured.

For example, in the first embodiment, as shown in fig. 9, in the plate spring 41, the boundary line between the base plate portion 41a and the blade portion 41b and the gap portion 41c is formed of an arc portion and a straight portion. The first curved portion 41b1 is offset from the circular arc portion to form a straight portion. Therefore, even if resistance is received from the L-shaped spacer 45 during sliding, stress such as torsion is not applied to the blade portions 41b, and durability can be maintained even when sliding is repeated. Further, since the lower portion of the gap portion 41c (between the root portions of the

blade portions

41b and 41b) is an arc portion, the strength of the plate spring 41 can be ensured without generating a crack or the like from the gap portion 41 c.

In addition, when the number of blade portions is odd as in the leaf spring 42 of the second embodiment, a three-point support structure in which the position where the blade portion 42b is in contact with and the position where the blade portion is not in contact with are asymmetrical with respect to the axis X is obtained. That is, since the force with which the blade portions 42b press the edge portion 45b is slightly dispersed from the end point P toward the middle of the second curved portion 42b2 due to slight elastic deformation of the edge portion 45b, the contact positions of the plurality of blade portions 42b with respect to the axis X are asymmetrical, and the seal portion 4 is less likely to tilt in the guide portion 21, so that uniform sealing can be achieved.

In the embodiment, since the seal portion 4 is sandwiched between the valve body 3A and the connection portion 3B, the seal portion 4 can be held in a simple structure with respect to the valve member 3 as a "moving member".

The L-shaped gaskets 45 are provided in a pair in a back-to-back manner in the seal portion 4. When the inside of the edge portion 45b of the L-shaped gasket 45 is at a high pressure, the high pressure acts to press the edge portion 45b against the guide surface 21a, and the seal portion 4 reliably seals the spaces on both sides of the seal portion 4 in both the first flow and the second flow.

In the above embodiments, the case where the blade portions are 12, 15, and 20 has been described, but if the blade portions are in the range of 12 to 20, the same operational effects as in the respective embodiments can be obtained even with a few blade portions.

In the above embodiment, the example in which the present invention is applied to the motor-operated valve has been described, but the

leaf springs

41, 42, 43 and the L spacer 45 of the respective embodiments may be applied to the sealing portion of the temperature expansion valve described in patent document 2, or the tooth spring and the L spacer of the piston of the four-way switching valve of patent document 3, for example, and the valve device of the present invention may be configured.

While the embodiments of the present invention have been described in detail with reference to the drawings, the specific configurations are not limited to these embodiments, and design changes and the like that do not depart from the scope of the present invention are also included in the present invention.

Description of the symbols

1-a valve housing, 2-a valve guide member, 21-a guide portion, 2A-a back pressure chamber, 3-a valve member, 3B-a leveling path, 3 c-a leveling path, 3A-a valve core, 3B-a coupling portion, 31-a cylindrical portion, 32-a boss portion, 33-a coupling shaft, 34-a boss portion, 4-a seal portion, 41-a plate spring, 41 a-a base plate portion, 41B-a blade portion, 41B 1-a first bend portion, 41B 2-a second bend portion, 42-a plate spring, 42A-a base plate portion, 42B-a blade portion, 42B 1-a first bend portion, 42B 2-a second bend portion, 43-a plate spring, 43A-a base plate portion, 43B 1-a first bend portion, 43B 2-a second bend portion, 45-L packing, 45 a-a base portion, 45B-an edge portion, 46-a reinforcement plate, and X-axis.

Claims

1. A valve device is provided with:

a cylindrical guide portion;

a moving member having a valve that moves along an axis of the guide portion to control a flow of the fluid; and

a sealing part which is provided on the moving member and is fitted in the guide part,

the differential pressure of the fluid in the spaces on both sides of the sealing portion in the axial direction in the guide portion is applied to the moving member,

the above-mentioned valve device is characterized in that,

the sealing portion includes: an L-shaped pad including an edge portion in sliding contact with an inner peripheral surface of the guide portion and a base portion held by the moving member; and a leaf spring disposed inside the L-shaped pad and pressing the edge portion toward the inner circumferential surface of the guide portion,

the leaf spring is composed of a base plate portion held by the moving member, and a plurality of blade portions radially formed on the outer periphery of the base plate portion and pressing the edge portion of the L-pad from the inside, and has a first bent portion at a boundary portion between the blade portion and the base plate portion, and a second bent portion outside the first bent portion and in contact with the edge portion,

the number of the blade portions is 12 to 20, the width of the blade portions is larger than the width of the gap portion between the blade portions, and the edge portion of the L-shaped pad is pressed by a vertex of a 2 n-sided polygon formed by end points of the second bent portions of the n blade portions.

2. The valve device according to claim 1,

the width α' of the gap portion and the width β of the blade portion have the following relationship:

α′≤β≤2.1·α′。

3. the valve device according to claim 1 or 2,

the first curved portion is formed at a linear portion of a side portion of the blade portion.

4. The valve device according to claim 1 or 2,

the lower portion of the gap portion between the root portions of the blade portions is an arc portion.

5. The valve device according to claim 1 or 2,

the number of the blade parts is an odd number.

6. The valve device according to claim 1 or 2,

the moving member includes a valve body and a coupling portion, and the base portion of the L-shaped gasket and the base plate portion of the plate spring are sandwiched between the valve body and the coupling portion, so that the sealing portion is sandwiched between the moving member and the valve body.

7. The valve device according to claim 1 or 2,

the sealing part comprises a pair of the plate springs, a pair of the L gaskets, and a reinforcing plate between the L gaskets,

the pair of L-shaped gaskets are disposed such that the pair of edge portions face outward in the axial direction, the reinforcing plate is sandwiched between the pair of base portions, and the seal portion is sandwiched between the moving members.