JPWO2020137268A1 - Damping force adjustable shock absorber and solenoid - Google Patents

Abstract

A non-magnetic ring is provided between the first stator core and the second stator core, which form the main part of the solenoid, located on the inner peripheral side of the coil. The non-magnetic ring is joined to the first and second fixed cores (first and second stator cores) by a brazed portion so as to increase the magnetic flux density of the magnetic circuit with respect to the movable core (plunger). .. A non-magnetic ring made of a non-magnetic material such as austenitic stainless steel has an inner diameter larger or smaller than the inner diameter of the first and second stator cores, and a radial gap is formed between the non-magnetic ring and the plunger. There is.

Description

The present invention relates to, for example, a damping force adjusting shock absorber and a solenoid that buffer the vibration of a vehicle.

In general, a suspension device such as a semi-active suspension mounted on a vehicle is provided with a damping force adjusting shock absorber that variably adjusts the damping force according to the traveling conditions, behavior, and the like of the vehicle. Further, as a damping force adjusting shock absorber, one using a solenoid as an electromagnetic proportional actuator for variably adjusting the damping force is known. For example, Patent Document 1 describes, as this type of solenoid, a coil that generates a magnetic force by energization, a first and second fixed iron core (stator core) that is arranged on the inner peripheral side of the coil and is made of a magnetic material, and the like. A non-magnetic member that connects the first and second fixed iron cores in the axial direction, and a movable iron core that is arranged on the inner peripheral side of the first and second fixed iron cores and the non-magnetic member and is movable in the axial direction ( The one configured by the plunger) is described.

Further, Patent Document 2 describes a method using a brazing means for joining a non-magnetic member between the first and second fixed iron cores. In this case, for example, after joining the second fixed iron core and the non-magnetic member by brazing, the inner peripheral surface thereof is cut to form a flush surface without a step. This enhances the slidability of the movable iron core. Further, Patent Document 3 describes a configuration in which a thin-walled portion for partially reducing the magnetic path cross-sectional area is provided between the first and second fixed iron cores. As a result, the magnetic flux density passing through the movable iron core is increased between the first and second fixed iron cores, and the performance as a solenoid is improved.

Japanese Unexamined Patent Publication No. 2014-73018 JP-A-2009-127692 Japanese Unexamined Patent Publication No. 2017-118124

By the way, in the solenoid shown in the above patent document, a non-magnetic member is bonded to the first and second fixed iron cores, and the non-magnetic member increases the magnetic flux density of the magnetic circuit with respect to the movable iron core. However, when the non-magnetic member is machined (for example, the inner peripheral surface is cut) after joining, there is a problem that the magnetic characteristics change due to the machining strain and the non-magnetic member is easily magnetized. Further, when a thin-walled portion is provided between the first and second fixed cores to partially reduce the magnetic path cross-sectional area, the thin-walled portion reduces the mechanical strength of the entire fixed core, resulting in durability. There is a problem that the life is shortened.

The present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is that the characteristics of the non-magnetic member can be maintained, and the magnetic flux density with respect to the movable core between the first and second fixed cores. It is an object of the present invention to provide a damping force adjusting shock absorber and a solenoid capable of maintaining a high value.

In order to solve the above-mentioned problems, one embodiment of the present invention includes a cylinder in which a working fluid is sealed, a piston that is inserted into the cylinder and defines the inside of the cylinder into a rod side chamber and a bottom side chamber, and the above. A piston rod connected to a piston and extending to the outside of the cylinder, a flow path in which the working fluid flows due to the movement of the piston rod, and a damping force adjusting valve provided in the flow path whose opening / closing operation is adjusted by a solenoid. The solenoid is a damping force adjusting shock absorber comprising A non-magnetic member provided between the first and second fixed iron cores and integrally fixed to the first and second fixed iron cores by brazing, the first and second fixed iron cores and the said A movable iron core arranged on the inner peripheral side of the non-magnetic member and provided so as to be movable in the axial direction, a shaft portion provided on the movable iron core, and first and second bushes for supporting the shaft portion are provided. The valve body of the damping force adjusting valve is provided at the end of the shaft portion on the side of the second fixed iron core, and the non-magnetic member is compared with the inner diameter of the first and second fixed iron cores. The inner diameter of the is large or small.

Further, the solenoid according to the embodiment of the present invention includes a coil that generates a magnetic force by energization, first and second fixed iron cores provided on the inner peripheral side of the coil, and the first and second fixed iron cores. A non-magnetic member provided between the first and second fixed iron cores and integrally fixed to the first and second fixed iron cores by brazing, and the inner peripheral side of the first and second fixed iron cores and the non-magnetic member. The first and second bushes are provided with a movable iron core arranged in the movable iron core and provided so as to be movable in the axial direction, a shaft portion provided on the movable iron core, and first and second bushes for supporting the shaft portion. The inner diameter of the non-magnetic member is larger or smaller than the inner diameter of the fixed iron core of the above.

Further, in one embodiment of the present invention, a cylinder in which a working fluid is sealed, a piston inserted into the cylinder and defining the inside of the cylinder into a rod side chamber and a bottom side chamber, and a piston connected to the piston are described. A piston rod extending to the outside of the cylinder, a flow path in which the working fluid flows due to the movement of the piston rod, and a damping force adjusting valve provided in the flow path and whose opening / closing operation is adjusted by a solenoid are provided. The solenoid is a damping force adjustment type shock absorber, and the solenoid is a coil that generates a magnetic force by energization, a first and second fixed iron cores provided on the inner peripheral side of the coil, and the first and second fixings. A non-magnetic member provided between the iron cores and integrally fixed to the first and second fixed iron cores by brazing, and the inner circumferences of the first and second fixed iron cores and the non-magnetic member. A movable iron core arranged on the side and movable in the axial direction, a shaft portion provided on the inner peripheral side of the movable iron core, and first and second bushes for supporting the shaft portion are provided. A valve body of the damping force adjusting valve is provided at the end of the shaft portion on the side of the second fixed iron core, and the inner diameter portion defining the inner diameter of the non-magnetic member is not machined after brazing. It is characterized by that.

According to one embodiment of the present invention, it is possible to suppress changes in the characteristics of the non-magnetic member due to the influence of heat or the like, and maintain a high magnetic flux density passing through the movable core between the first and second fixed cores. be able to.

It is a vertical cross-sectional view which shows the damping force adjustment type hydraulic shock absorber provided with the solenoid by embodiment of this invention. FIG. 5 is an enlarged cross-sectional view showing a damping force adjusting valve and a solenoid in FIG. 1. It is sectional drawing which removes the damping force adjustment valve in FIG. 2, and shows the solenoid enlarged. FIG. 5 is a cross-sectional view showing a state in which the first and second stator cores and the non-magnetic ring of the solenoids in FIG. 3 are preassembled.

Hereinafter, a case where the damping force adjusting shock absorber and the solenoid according to the embodiment of the present invention are applied to the damping force adjusting hydraulic shock absorber will be described in detail with reference to FIGS. 1 to 4.

In FIG. 1, a damping force adjusting type hydraulic shock absorber 1 (hereinafter referred to as a hydraulic shock absorber 1) is provided with a solenoid 33 described later. The hydraulic shock absorber 1 includes an outer cylinder 2, an inner cylinder 4, a piston 5, a piston rod 8, a rod guide 9, a damping force adjusting device 17, and the like. In the following description, for example, one side in the axial direction of the outer cylinder 2 and the inner cylinder 4 will be referred to as a lower side, a lower side or a lower end side, and the other side in the axial direction will be described as an upper side, an upper side or an upper end side. And.

The bottom end side of the bottomed cylindrical outer cylinder 2 forming the outer shell of the hydraulic shock absorber 1 is closed by the bottom cap 3, and the upper end side of the outer cylinder 2 is a crimped portion 2A bent inward in the radial direction. .. A rod guide 9 and a sealing member 10 are provided between the caulking portion 2A and the inner cylinder 4. On the other hand, on the lower side of the outer cylinder 2, an opening 2B is formed concentrically with the connection port 12C of the intermediate cylinder 12 described later, and a damping force adjusting device 17 described later is attached facing the opening 2B. Further, the bottom cap 3 is provided with a mounting eye 3A that is mounted on the wheel side of the vehicle, for example.

An inner cylinder 4 is provided in the outer cylinder 2 coaxially with the outer cylinder 2. The lower end side of the inner cylinder 4 is fitted and attached to the bottom valve 13, and the upper end side is fitted and attached to the rod guide 9. A working liquid as a working fluid is sealed in the inner cylinder 4. The working liquid is not limited to oil and oil, and may be, for example, water mixed with additives.

An annular reservoir chamber A is formed between the inner cylinder 4 and the outer cylinder 2, and gas is sealed in the reservoir chamber A together with the oil liquid. This gas may be air in an atmospheric pressure state, or a gas such as compressed nitrogen gas may be used. Further, an oil hole 4A that allows the rod-side oil chamber B to always communicate with the annular oil chamber D is bored in the radial direction at an intermediate position in the length direction (axial direction) of the inner cylinder 4.

The piston 5 is slidably fitted in the inner cylinder 4. The inside of the inner cylinder 4 of the piston 5 is defined as a rod side chamber (rod side oil chamber B) and a bottom side chamber (bottom side oil chamber C). A plurality of oil passages 5A and 5B that enable communication between the rod-side oil chamber B and the bottom-side oil chamber C are formed in the piston 5 so as to be separated from each other in the circumferential direction.

Here, a disc valve 6 on the extension side is provided on the lower end surface of the piston 5. The extension-side disc valve 6 opens when the pressure in the rod-side oil chamber B exceeds the relief set pressure when the piston 5 slides and displaces upward in the extension stroke of the piston rod 8. The pressure is relieved to the bottom side oil chamber C side via each oil passage 5A. This relief set pressure is set to a pressure higher than the valve opening pressure when the damping force adjusting device 17 described later is set to hard.

A contraction-side check valve 7 is provided on the upper end surface of the piston 5 to open the valve when the piston 5 slides and displaces downward in the contraction stroke of the piston rod 8, and closes the valve at other times. The check valve 7 allows the oil liquid in the bottom side oil chamber C to flow in each oil passage 5B toward the rod side oil chamber B, and prevents the oil liquid from flowing in the opposite direction. Is what you do. The valve opening pressure of the check valve 7 is set to a pressure lower than the valve opening pressure when the damping force adjusting device 17 described later is softly set, and the check valve 7 does not substantially generate a damping force. The fact that this substantially no damping force is generated is a force equal to or less than the friction of the piston 5 and the seal member 10, and does not affect the movement of the vehicle.

The piston rod 8 extends in the inner cylinder 4 in the axial direction (upward and downward directions). The lower end side of the piston rod 8 is inserted into the inner cylinder 4 and is fixed to the piston 5 by a nut 8A or the like. Further, the upper end side of the piston rod 8 projects so as to extend to the outside of the outer cylinder 2 and the inner cylinder 4 via the rod guide 9.

A stepped cylindrical rod guide 9 is provided on the upper end side of the inner cylinder 4. The rod guide 9 positions the upper portion of the inner cylinder 4 at the center of the outer cylinder 2 and guides the piston rod 8 so as to be slidable in the axial direction on the inner peripheral side thereof. Further, an annular seal member 10 is provided between the rod guide 9 and the crimped portion 2A of the outer cylinder 2. The seal member 10 is formed by baking an elastic material such as rubber on an annular metal plate through which the piston rod 8 is inserted in the center, and the inner circumference of the seal member 10 is in sliding contact with the outer peripheral surface of the piston rod 8 to be in contact with the piston rod 8. To seal.

Further, the seal member 10 is formed with a lip seal 10A as a check valve extending so as to come into contact with the rod guide 9 on the lower surface side. The lip seal 10A is arranged between the oil sump chamber 11 and the reservoir chamber A so that the oil liquid or the like in the oil sump chamber 11 flows toward the reservoir chamber A side through the return passage 9A of the rod guide 9. It forgives and blocks the reverse flow.

An intermediate cylinder 12 made of a cylinder is arranged between the outer cylinder 2 and the inner cylinder 4. The intermediate cylinder 12 is attached to, for example, the outer peripheral side of the inner cylinder 4 via upper and lower tubular seals 12A and 12B. The intermediate cylinder 12 has an annular oil chamber D extending inside so as to surround the outer peripheral side of the inner cylinder 4 over the entire circumference, and the annular oil chamber D is an oil chamber independent of the reservoir chamber A. The annular oil chamber D is always in communication with the rod side oil chamber B by a radial oil hole 4A formed in the inner cylinder 4. The annular oil chamber D is a flow path in which the working liquid flows due to the movement of the piston rod 8. Further, on the lower end side of the intermediate cylinder 12, a connection port 12C to which the tubular holder 20 of the damping force adjusting valve 18 described later is attached is provided.

The bottom valve 13 is located on the lower end side of the inner cylinder 4 and is provided between the bottom cap 3 and the inner cylinder 4. The bottom valve 13 is a valve body 14 that defines a reservoir chamber A and a bottom side oil chamber C between the bottom cap 3 and the inner cylinder 4, and a disc valve on the reduction side provided on the lower surface side of the valve body 14. It is composed of 15 and an extension side check valve 16 provided on the upper surface side of the valve body 14. Oil passages 14A and 14B that allow communication between the reservoir chamber A and the bottom side oil chamber C are formed in the valve body 14 at intervals in the circumferential direction, respectively.

The disc valve 15 on the reduction side opens when the pressure in the oil chamber C on the bottom side exceeds the relief set pressure when the piston 5 slides and displaces downward in the reduction stroke of the piston rod 8. Is relieved to the reservoir chamber A side via each oil passage 14A. This relief set pressure is set to a pressure higher than the valve opening pressure when the damping force adjusting device 17 described later is set to hard.

The extension-side check valve 16 opens when the piston 5 slides and displaces upward during the extension stroke of the piston rod 8, and closes at other times. The extension-side check valve 16 allows the oil liquid in the reservoir chamber A to flow in each oil passage 14B toward the bottom-side oil chamber C, and prevents the oil liquid from flowing in the opposite direction. Is what you do. The valve opening pressure of the extension-side check valve 16 is set to a pressure lower than the valve opening pressure when the damping force adjusting device 17 described later is softly set, and substantially no damping force is generated.

Next, the damping force adjusting device 17 for variably adjusting the generated damping force of the hydraulic shock absorber 1 will be described with reference to FIG. 2 in addition to FIG. In the damping force adjusting device 17 of FIG. 2, the plunger 48 (actuating pin 49) is shown in FIG. 2 by energizing the coil 34A of the solenoid 33 (for example, controlling to generate a hard damping force) from the outside. It shows a state in which the pilot valve body 32 has moved to the left side (that is, the valve closing direction in which the pilot valve body 32 is seated on the valve seat portion 26E of the pilot body 26).

As shown in FIG. 1, the damping force adjusting device 17 is arranged so that its base end side (left end side in FIG. 1) is interposed between the reservoir chamber A and the annular oil chamber D, and the tip end side (FIG. 1). The right end side of the outer cylinder 2) is provided so as to project outward in the radial direction from the lower side of the outer cylinder 2. The damping force adjusting device 17 includes a damping force adjusting valve 18 that generates a damping force having a hard or soft characteristic by variably controlling the flow of the oil liquid from the annular oil chamber D to the reservoir chamber A, and the damping force adjusting valve 18. It is configured to include a solenoid 33, which will be described later, for adjusting the opening / closing operation of the valve 18.

That is, the valve opening pressure of the damping force adjusting valve 18 is adjusted by the solenoid 33 used as the damping force variable actuator, whereby the generated damping force is variably controlled to a hard or soft characteristic. The damping force adjusting valve 18 is a valve whose opening / closing operation is adjusted by a solenoid 33, and is a flow path in which a flow of a working fluid is generated by the movement of the piston rod 8 (for example, between the annular oil chamber D and the reservoir chamber A). It is provided in.

Here, the damping force adjusting valve 18 has a substantially cylindrical valve case 19 provided so that the base end side thereof is fixed around the opening 2B of the outer cylinder 2 and the tip end side protrudes outward in the radial direction from the outer cylinder 2. , The tubular holder 20 whose base end side is fixed to the connection port 12C of the intermediate cylinder 12 and whose tip end side is an annular flange portion 20A and is arranged inside the valve case 19 with a gap, and the tubular holder 20. It is configured to include a valve member 21 and the like that come into contact with the flange portion 20A.

The base end side of the valve case 19 is an annular inner flange portion 19A extending inward in the radial direction, and the tip end side of the valve case 19 is a coupling that connects the valve case 19 and a cover member 51 of a solenoid 33 described later. It is a male screw portion 19B to which the ring 52 is screwed. An annular oil that always communicates with the reservoir chamber A between the inner peripheral surface of the valve case 19 and the outer peripheral surface of the valve member 21, and further between the inner peripheral surface of the valve case 19 and the outer peripheral surface of the pilot body 26 or the like. Room 19C.

The inside of the tubular holder 20 is an oil passage 20B in which one side communicates with the annular oil chamber D and the other side extends to the position of the valve member 21. An annular spacer 22 is provided between the flange portion 20A of the tubular holder 20 and the inner flange portion 19A of the valve case 19 in a sandwiched state. The spacer 22 is provided with a plurality of notches 22A that serve as radial oil passages in order to communicate the oil chamber 19C and the reservoir chamber A. In this embodiment, the spacer 22 is provided with a notch 22A for forming an oil passage. However, the inner flange portion 19A of the valve case 19 may be provided with notches for forming an oil passage in a radial pattern. In this configuration, the spacer 22 can be omitted to reduce the number of parts.

The valve member 21 is provided with a central hole 21A located at the center in the radial direction and extending in the axial direction. Further, the valve member 21 is provided with a plurality of oil passages 21B around the central hole 21A so as to be spaced apart from each other in the circumferential direction, and one side (left side of FIGS. 1 and 2) of each of these oil passages 21B is a cylinder. It is always in communication with the oil passage 20B of the shape holder 20. Further, on the end surface of the other side (right side of FIGS. 1 and 2) of the valve member 21, an annular recess 21C formed so as to surround the other side opening of the oil passage 21B and a radial outer side of the annular recess 21C. An annular valve seat 21D is provided at the position where the main valve 23, which will be described later, is taken off and seated. Here, each oil passage 21B of the valve member 21 is a main valve between the oil passage 20B of the tubular holder 20 communicating with the annular oil chamber D and the oil chamber 19C of the valve case 19 communicating with the reservoir chamber A. It becomes a flow path through which the pressure oil of the flow rate corresponding to the opening degree of 23 flows.

The main valve 23 is composed of a disc valve whose inner peripheral side is sandwiched between the valve member 21 and the large diameter portion 24A of the pilot pin 24. The outer peripheral side of the main valve 23 is detached and seated on the annular valve seat 21D of the valve member 21. An elastic seal member 23A is fixed to the outer peripheral portion of the main valve 23 on the back surface side by means such as baking. The main valve 23 is opened by receiving pressure from the oil passage 21B side (annular oil chamber D side) of the valve member 21 and separating from the annular valve seat 21D. As a result, the oil passage 21B (annular oil chamber D side) of the valve member 21 is communicated with the oil chamber 19C (reservoir chamber A side) via the main valve 23, and the pressure oil flow rate at this time is the pressure oil flow rate of the main valve 23. It is variably adjusted according to the opening degree.

The pilot pin 24 is formed in a stepped cylindrical shape, and an annular large diameter portion 24A is provided at an axially intermediate portion thereof. The pilot pin 24 has a central hole 24B extending in the axial direction on the inner peripheral side thereof, and a small diameter hole (orifice 24C) is formed at one end of the central hole 24B (the end on the tubular holder 20 side). .. One end side (the left end side of FIGS. 1 and 2) of the pilot pin 24 is press-fitted into the center hole 21A of the valve member 21, and the main valve 23 is sandwiched between the large diameter portion 24A and the valve member 21. The other end side of the pilot pin 24 (the right end side of FIGS. 1 and 2) is fitted into the center hole 26C of the pilot body 26. In this state, an oil passage 25 extending in the axial direction is formed between the center hole 26C of the pilot body 26 and the other end side of the pilot pin 24. The oil passage 25 communicates with a back pressure chamber 27 formed between the main valve 23 and the pilot body 26. In other words, a plurality of oil passages 25 extending in the axial direction are provided in the circumferential direction on the side surface on the other end side of the pilot pin 24, and the other circumferential positions are press-fitted into the central hole 26C of the pilot body 26.

The pilot body 26 is formed as a substantially bottomed tubular body having a cylindrical portion 26A having a stepped hole formed inside and a bottom portion 26B that closes the cylindrical portion 26A. The bottom portion 26B of the pilot body 26 is provided with a central hole 26C into which the other end side of the pilot pin 24 is fitted. On the outer peripheral side of the bottom portion 26B of the pilot body 26, a protruding tubular portion 26D extending to the valve member 21 side (that is, the left side of FIGS. 1 and 2) is integrally provided over the entire circumference thereof. An elastic sealing member 23A of the main valve 23 is liquid-tightly fitted to the inner peripheral surface of the protruding cylinder portion 26D, whereby a back pressure chamber 27 is formed between the main valve 23 and the pilot body 26. ing. The back pressure chamber 27 generates a pressure that presses the main valve 23 in the valve closing direction, that is, in the direction in which the main valve 23 is seated on the annular valve seat 21D of the valve member 21.

The bottom portion 26B of the pilot body 26 is provided with a valve seat portion 26E located on the other end side (right end side of FIGS. 1 and 2) on which the pilot valve body 32 described later is taken off and seated so as to surround the central hole 26C. Has been done. Further, inside the cylindrical portion 26A of the pilot body 26, a return spring 28 for urging the pilot valve body 32 in a direction away from the valve seat portion 26E of the pilot body 26, and a solenoid 33 described later are in a non-energized state (pilot). A disc valve 29 constituting a fail-safe valve (when the valve body 32 is farthest from the valve seat portion 26E), a holding plate 30 having an oil passage 30A formed on the center side, and the like are arranged.

A cap 31 is fitted and fixed to the open end of the cylindrical portion 26A of the pilot body 26 with a return spring 28, a disc valve 29, a holding plate 30, and the like arranged inside the cylindrical portion 26A. Notches 31A are formed in the cap 31 at four positions separated in the circumferential direction, for example. These notches 31A serve as a flow path for flowing the oil liquid flowing toward the solenoid 33 side through the oil passage 30A of the holding plate 30 to the oil chamber 19C (reservoir chamber A side) in the direction of the arrow X shown in FIG. ing.

The pilot valve body 32 constitutes a pilot valve together with the pilot body 26. The pilot valve body 32 is formed in a stepped cylindrical shape, and the tip portion for taking off and seating on the valve seat portion 26E of the pilot body 26 is a tapered portion. Inside the pilot valve body 32, an operating pin 49 of a solenoid 33, which will be described later, is fixed in a fitted state, and the valve opening pressure of the pilot valve body 32 is adjusted according to the energization of the solenoid 33. ing. A flange portion 32A serving as a spring receiver is formed on the base end side of the pilot valve body 32 over the entire circumference. The flange portion 32A comes into contact with the disc valve 29 when the solenoid 33 is in a non-energized state (that is, when the pilot valve body 32 is displaced to the fully open position farthest from the valve seat portion 26E), and the pilot valve body 32 comes into contact with the disc valve 29. It regulates the opening of valves any more.

Next, the solenoid 33 constituting the damping force adjusting device 17 together with the damping force adjusting valve 18 will be described with reference to FIGS. 2, 3 and 4.

The solenoid 33 is used in a damping force adjusting shock absorber to adjust the opening / closing operation of the damping force adjusting valve 18. That is, the solenoid 33 used as the damping force variable actuator of the damping force adjusting device 17 includes a mold coil 34, a first stator core 36, a core lid 37, a second stator core 40, a non-magnetic ring 44, a plunger 48, and an operating pin. It is composed of 49, a cover member 51, and the like.

The mold coil 34 is formed in a substantially cylindrical shape by integrally covering (molding) the coil 34A wound around the coil bobbin with a resin member 34B such as a thermosetting resin. A part of the mold coil 34 in the circumferential direction is a cable extraction portion (not shown) protruding outward in the axial direction or the radial direction, and an electric wire cable (not shown) is connected to this cable extraction portion. The coil 34A becomes an electromagnet and generates a magnetic force by supplying electric power (energization) through a cable from the outside.

Of the resin member 34B of the mold coil 34, a seal groove 34C is formed on the side surface (axial end surface) facing the cover member 51 (plate 51B) described later over the entire circumference. A seal member (for example, an O-ring 35) is mounted in the seal groove 34C. The O-ring 35 tightly seals between the mold coil 34 and the cover member 51 (plate 51B). As a result, it is possible to prevent dust including rainwater and muddy water from entering the first and second stator cores 36 and 40 side through between the cover member 51 and the mold coil 34.

The coil used in the present invention is not limited to the molded coil 34 composed of the coil 34A and the resin member 34B, and other coils may be used. For example, in a state where the coil is wound around a coil bobbin made of an electrically insulating material, the outer periphery of the coil may be covered by an overmold (not shown) in which a resin material is molded from above (outer peripheral side). ..

The first stator core 36 constitutes a first fixed iron core provided on the inner peripheral side of the mold coil 34 (coil 34A). The first stator core 36 is formed as a cylindrical cylinder by a magnetic material such as low carbon steel or carbon steel for machine structure (S10C). The first stator core 36 is formed with a small-diameter tubular portion 36A for joining on one side in the axial direction (left side in FIGS. 3 and 4), and the small-diameter tubular portion 36A is brazed with a non-magnetic ring 44 described later. It is joined by the attachment portion 45. The inner diameter of the first stator core 36 is formed to be slightly larger than the outer diameter of the plunger 48, which will be described later, and the plunger 48 can move in the first stator core 36 in the axial direction.

A bottomed cylindrical core lid 37 is fitted and provided on the other side of the first stator core 36 in the axial direction (right side of FIGS. 3 and 4). The core lid 37 is formed in a bottomed cylindrical shape with the same magnetic material as the first stator core 36, and closes the first stator core 36 from the other side in the axial direction (left side in FIGS. 2 and 3). .. A bottomed stepped hole 37A is formed inside the core lid 37, and the stepped hole 37A is provided with a first bush 38 for slidably supporting the operation pin 49 described later. There is. On the outer peripheral side of the core lid 37, a seal groove 37B (see FIG. 3) is provided over the entire circumference between the core lid 37 and the inner circumference of the first stator core 36. An O-ring 39 as a sealing member is mounted on the seal groove 37B, and the O-ring 39 tightly seals the space between the first stator core 36 and the core lid 37.

Further, the core lid 37 is arranged so that the end surface of the bottom portion thereof faces the plate 51B of the cover member 51, which will be described later, with a gap in the axial direction. This axial gap has a function of preventing an axial force from being directly applied to the first stator core 36 from the plate 51B side of the cover member 51 via the core lid 37. The core lid 37 does not necessarily have to be formed of a magnetic material, and can be formed of a rigid metal material, a ceramic material, or a fiber-reinforced resin material.

The second stator core 40 constitutes a second fixed iron core provided on the inner peripheral side of the mold coil 34 (coil 34A) so as to be separated from the first stator core 36 on one side in the axial direction. Like the first stator core 36 (first fixed iron core), the second stator core 40 is formed in a stepped tubular shape by a magnetic material such as low carbon steel or carbon steel for machine structure (S10C). The second stator core 40 has a cylindrical tubular portion 40A whose inner peripheral side is a stepped hole 40F described later, and an annular shape extending radially outward from the outer circumference on one axial side of the tubular portion 40A. The portion 40B is formed as an integral body including a tubular fitting portion 40C that protrudes from the outer peripheral side of the annular portion 40B toward one side in the axial direction (damping force adjusting valve 18 side).

The tubular portion 40A of the second stator core 40 is provided with a circular recessed portion 40D on the other side surface facing the plunger 48 described later in the axial direction. The recessed portion 40D is formed as a circular groove having a diameter slightly larger than that of the plunger 48 so that the plunger 48 described later can be inserted and exited by magnetic force inside the recessed portion 40D. Further, on the other side of the tubular portion 40A, a conical protrusion 40E is provided so as to surround the periphery (outer circumference) of the concave recess portion 40D. The outer peripheral surface of the conical protrusion 40E is formed as a conical surface so that the magnetic characteristic is linear between the tubular portion 40A of the second stator core 40 and the plunger 48. .. That is, the conical protrusion 40E projects in a cylindrical shape from the outer peripheral side of the tubular portion 40A of the second stator core 40 toward the other side in the axial direction, and the outer peripheral surface thereof protrudes in a tubular shape from one side in the axial direction to the other side (FIG. 3, FIG. It is a conical surface that is tapered in a tapered shape so that the outer diameter dimension gradually decreases toward the concave recess 40D shown in FIG. 4 (from the left side to the right side).

Further, as shown in FIGS. 3 and 4, stepped holes 40F are formed on the inner peripheral side of the tubular portion 40A, and in order to slidably support the operation pin 49 described later in the stepped holes 40F. The second bush 41 of the above is fitted and provided. On the other hand, the annular portion 40B of the second stator core 40 is formed with a seal groove 40G on which a seal member (for example, an O-ring 42) is mounted on the other side surface facing the mold coil 34, and the O-ring 42 is molded. The coil 34 and the annular portion 40B are hermetically sealed.

As shown in FIG. 2, the cap 31 of the damping force adjusting valve 18 is fitted (internally fitted) on the inner peripheral side of the fitting portion 40C. Further, the valve case 19 of the damping force adjusting valve 18 is fitted (outerly fitted) on the outer peripheral side of the fitting portion 40C. Further, a seal groove 40H is provided on the outer peripheral surface of the fitting portion 40C over the entire circumference. An O-ring 43 as a sealing member is mounted on the seal groove 40H, and the O-ring 43 is liquid-tight between the second stator core 40 (fitting portion 40C) and the valve case 19 of the damping force adjusting valve 18. It is sealed in.

The non-magnetic ring 44 is a non-magnetic member located between the first and second stator cores 36 and 40 and provided on the inner peripheral side of the mold coil 34 (coil 34A). The non-magnetic ring 44 is formed as a stepped cylinder by a non-magnetic material such as austenitic stainless steel. The non-magnetic ring 44 is composed of a thick-walled cylinder portion 44A in the middle in the axial direction and first and second fitting cylinder portions 44B and 44C protruding in the axial direction from both ends of the thick-walled cylinder portion 44A, respectively. There is.

Here, the non-magnetic ring 44 has the same outer diameter dimension of the thick-walled cylinder portion 44A and the fitting cylinder portions 44B and 44C. However, as shown in FIG. 4, the thick-walled cylinder portion 44A is formed in the dimension D1 having the smallest inner diameter, and the first and second fitting cylinder portions 44B and 44C have the thick-walled cylinder portion 44A (dimension D1). It is formed to have a larger inner diameter. The first and second fitting cylinders 44B and 44C are formed of a non-magnetic material with a required wall thickness (thickness in the radial direction) so as to secure a desired coaxiality together with the thick cylinder portions 44A. ..

The first fitting cylinder portion 44B of the non-magnetic ring 44 is fitted to the small diameter cylinder portion 36A of the first stator core 36 from the outside, and both are joined by a brazing portion 45. Further, the second fitting cylinder portion 44C is fitted to the outer peripheral side of the cylinder portion 40A and the conical protrusion 40E of the second stator core 40, and both are joined by the brazing portion 46. The brazing portions 45 and 46 each use a brazing material made of pure copper brazing material to perform brazing treatment at 1000 ° C. or higher (pure copper brazing materialization treatment) to form the first and second non-magnetic rings 44. It is joined to the stator cores 36 and 40 of the above. After the brazing process, a quenching process is performed.

The brazed portions 45 and 46 have a thickness of, for example, about 25 to 51 μm, and the non-magnetic ring 44 is joined to the first and second stator cores 36 and 40. In this state, the inner diameter of the non-magnetic ring 44 (that is, the dimension D1 of the thick cylinder portion 44A) is larger than the inner diameter of the first stator core 36 and the inner diameter of the second stator core 40 (that is, that is, as shown in FIG. 4). , The radial dimension of the recessed portion 40D) is formed to be larger. The inner diameter of the non-magnetic ring 44 (that is, the dimension D1 of the thick cylinder portion 44A) is larger than the inner diameter of the first and second fixed iron cores (first and second stator cores 36 and 40). .. In the present embodiment, the inner diameter of the non-magnetic ring 44 is larger than the inner diameter of the first and second fixed iron cores, but the inner diameter of the non-magnetic ring 44 is the first and second fixed iron cores. The diameter may be smaller than the inner diameter of the fixed iron core. The inner diameter of the non-magnetic ring 44 is smaller or larger than the inner diameter of the first and second fixed iron cores, in other words, the non-magnetic ring 44 is used as the first and second fixed iron cores. It means that the inside is not cut after brazing (without cutting, there is a tolerance in the inner diameters of the non-magnetic ring 44, the first and second fixed iron cores, and all the inner diameters are the same in mass-produced products. Can never be).

The small-diameter tubular portion 36A of the first stator core 36 is formed with an annular gap 47 on the outer peripheral side thereof from the first fitting tubular portion 44B of the non-magnetic ring 44. The gap 47 is for pouring the brazing material (pure copper brazing) between the first stator core 36 (small diameter cylinder portion 36A) and the non-magnetic ring 44 (first fitting cylinder portion 44B) in a heat-melted state. This is the introduction route. The gap 47 functions as a gap for absorbing the difference in thermal expansion between the first and second stator cores 36 and 40 and the non-magnetic ring 44.

The brazing material of the brazed portion 46 is also between the second stator core 40 (cylinder portion 40A, outer peripheral surface of the conical protrusion 40E) and the non-magnetic ring 44 (second fitting cylinder portion 44C). An introduction path for pouring (pure copper brazing) in a heated and melted state is formed in the same manner as the gap 47. However, the non-magnetic ring 44 heats the brazing material (pure copper brazing) in order to join the second fitting cylinder portion 44C to the second stator core 40 (the cylinder portion 40A, the outer peripheral side of the conical protrusion 40E). When poured in a molten state, an axial external force is applied between the two to eliminate the gap as much as possible. However, a difference in thermal expansion occurs between the first and second stator cores 36 and 40 and the non-magnetic ring 44 due to the difference in the material.

Therefore, an axial gap 47 is formed between the small-diameter tubular portion 36A of the first stator core 36 and the first fitting tubular portion 44B of the non-magnetic ring 44 so as to extend over the entire circumference. In this way, the non-magnetic ring 44 is joined between the first and second stator cores 36 and 40 by brazing portions 45 and 46, and the material is different between the two by the quenching treatment after brazing. Even if a difference in thermal expansion due to the above occurs, the generation of strain based on this can be suppressed by the gap 47. The non-magnetic ring 44 as a non-magnetic member is provided between the first and second stator cores 36 and 40 (fixed iron cores), and is integrated with the first and second stator cores 36 and 40 by brazing. Is fixed to.

The plunger 48 as a movable iron core is arranged on the inner peripheral side of the first and second stator cores 36 and 40 (first and second fixed iron cores) and the non-magnetic ring 44 (non-magnetic member) and moves in the axial direction. It is provided as possible. That is, the plunger 48 is arranged on the inner peripheral side of the first and second stator cores 36 and 40 and the non-magnetic ring 44, and the first and second bushes 38 and 41 and the operating pin 49 are generated by the magnetic force generated in the coil 34A. It is provided so as to be movable in the axial direction via. The plunger 48 is fixedly provided to the actuating pin 49 extending through the central side thereof, and moves together with the actuating pin 49. The actuating pin 49 is axially slidably supported by the core lid 37 on the side of the first stator core 36 and the second stator core 40 via the first and second bushes 38 and 41.

Here, the plunger 48 is formed in a substantially cylindrical shape by an iron-based magnetic material like the first and second stator cores 36 and 40, and when a magnetic force is generated by the coil 34A, the second stator core 40 It generates a thrust in the direction of being attracted toward the recessed portion 40D of the. Further, the plunger 48 is formed with a plurality of communication passages 48A that are separated in the circumferential direction and extend in the axial direction (front and rear directions). In these communication passages 48A, the oil liquid in the first and second stator cores 36 and 40 smoothly circulates in each communication passage 48A while the plunger 48 is displaced in the axial direction together with the operation pin 49. This is a flow passage for suppressing the generation of flow resistance with respect to the plunger 48.

The actuating pin 49 is a shaft portion that transmits the thrust of the plunger 48 to the pilot valve body 32 of the damping force adjusting valve 18, and is formed by a hollow rod. A plunger 48 as a movable iron core is integrally fixed to the axially intermediate portion of the actuating pin 49 by means such as press fitting, whereby the plunger 48 and the actuating pin 49 are subassembled. Both sides of the operating pin 49 in the axial direction are slidable to the core lid 37 on the side of the first stator core 36 and the second stator core 40 (cylinder portion 40A) via the first and second bushes 38 and 41. Is supported by.

One end side (the left end portion in FIG. 2) of the operating pin 49 protrudes from the second stator core 40, and the pilot valve body 32 of the damping force adjusting valve 18 is fixed to the protruding end. Therefore, the pilot valve body 32 moves integrally in the axial direction together with the plunger 48 and the actuating pin 49. In other words, the valve opening set pressure of the pilot valve body 32 is a pressure value corresponding to the thrust of the plunger 48 based on the energization of the coil 34A. The plunger 48 is configured to open and close the pilot valve of the hydraulic shock absorber 1 (that is, the pilot valve body 32 with respect to the pilot body 26) by moving in the axial direction by the magnetic force from the coil 34A.

The back pressure chamber 50 is an oil chamber formed between the core lid 37 and the other end of the operating pin 49 (the right end in FIG. 2). The back pressure chamber 50 communicates with the center hole 24B side of the pilot pin 24 via a hollow rod (actuating pin 49). Therefore, the same pressure as the pilot valve body 32 that takes off and seats on the valve seat portion 26E of the pilot body 26 acts on the back pressure chamber 50. However, as for the pressure receiving area with respect to this pressure, the area where the other end surface of the operating pin 49 receives the pressure in the back pressure chamber 50 is such that the pilot valve body 32 (one end side of the operating pin 49) is between the valve seat portion 26E. It is smaller than the area to receive pressure.

As a result, the thrust to be transmitted from the plunger 48 to the pilot valve body 32 of the damping force adjusting valve 18 via the actuating pin 49 can be reduced by the difference in the pressure receiving area between the two. That is, by forming the back pressure chamber 50 with the core lid 37 on the other end side of the actuating pin 49, the back pressure chamber 50 is transmitted from the plunger 48 to the pilot valve body 32 of the damping force adjusting valve 18 via the actuating pin 49. The thrust force (for example, the magnetic force to be generated by the coil 34A of the mold coil 34) can be reduced, and the entire solenoid 33 can be made smaller and lighter.

The cover member 51 is a magnetic material cover that covers the outer periphery of the coil 34A. The cover member 51 is formed as a yoke using a magnetic material (magnetic material), and forms a magnetic circuit (magnetic path) on the outer peripheral side of the mold coil 34 (coil 34A). Here, the cover member 51 is formed in a bottomed cylindrical shape as a whole, and the cylindrical case 51A and the other end side of the cylindrical case 51A (the right end in FIGS. 2 and 3) are formed. It is roughly composed of a plate 51B to be closed. The tubular case 51A is provided with a notch (not shown) for exposing the cable extraction portion of the mold coil 34 described above from the cover member 51.

Here, the plate 51B of the cover member 51 is provided with a fitting recess 51C into which the core lid 37 (bottom side) of the first stator core 36 is inserted or accommodated. The first stator core 36 can transfer magnetic flux to and from the plate 51B of the cover member 51 by fitting the bottom side of the core lid 37 into the fitting recess 51C.

On the other hand, the inner peripheral surface of the tubular case 51A of the cover member 51 faces the outer peripheral surface of the mold coil 34 with a gap. This gap is configured to suppress the radial force applied to the cover member 51 from being directly applied to the mold coil 34. Further, the outer peripheral surface of the annular portion 40B of the second stator core 40 is in contact with the inner peripheral surface of the tubular case 51A by, for example, light press fitting, and the cover member 51 and the second stator core 40 (annular portion 40B) are in contact with each other. Magnetic flux can be transferred to and from.

At the end of the cover member 51 on the opening side (that is, the end on one side in the axial direction of the tubular case 51A located on the left side of FIG. 2), an engaging convex portion protruding radially outward from other parts. 51Ds are provided (over the entire circumference or at a plurality of locations separated in the circumferential direction). The engaging convex portion 51D is engaged with a coupling ring 52 screwed to the valve case 19 of the damping force adjusting valve 18.

The coupling ring 52 is formed in a substantially cylindrical shape, and inside the coupling ring 52, there is a female screw portion 52A screwed into the male screw portion 19B of the valve case 19, and an outer diameter dimension of the engaging convex portion 51D of the tubular case 51A. A collar-shaped engaging portion 52B extending inward in the radial direction is provided so as to be smaller than the above. The coupling ring 52 is formed by screwing the female threaded portion 52A and the male threaded portion 19B of the valve case 19 in a state where the flange-shaped engaging portion 52B is in contact with the engaging convex portion 51D of the tubular case 51A. It is a coupling member that integrally connects the damping force adjusting valve 18 and the solenoid 33.

The solenoid 33 and the hydraulic shock absorber 1 according to the present embodiment have the above-described configuration, and the operation thereof will be described next.

First, when the hydraulic shock absorber 1 is mounted on a vehicle such as an automobile, for example, the protruding end (upper end) side of the piston rod 8 is mounted on the vehicle body side, and the mounting eye 3A side provided on the bottom cap 3 is mounted on the wheel side. Be done. Then, the solenoid 33 of the damping force adjusting device 17 is connected to a control device (controller) provided on the vehicle body side of the vehicle via an electric wiring cable (none of which is shown) or the like.

When the vehicle is traveling, when vibrations in the upward and downward directions occur due to unevenness of the road surface or the like, the piston rod 8 is displaced so as to extend or contract from the outer cylinder 2, and a damping force is generated by the damping force adjusting device 17 or the like. It can buffer the vibration of the vehicle. At this time, the controller variably controls the generated damping force of the hydraulic shock absorber 1 by changing the current value of the control signal energizing the coil 34A of the solenoid 33 and adjusting the valve opening pressure of the pilot valve body 32. can do.

Here, the magnetic force (magnetic flux) generated by the coil 34A of the solenoid 33 passes from the first stator core 36 to the movable iron core (plunger 48) side so as to avoid the non-magnetic ring 44 which is a non-magnetic member, and from the plunger 48 to the first. The first solenoid core passes through the stator core 40 of 2 (that is, the conical protrusion 40E, the tubular portion 40A, the annular portion 40B and the fitting portion 40C), and further passes through the tubular case 51A and the plate 51B of the cover member 51. The magnetic circuit is configured so as to return to 36.

In this case, the magnetic circuit is a contact portion (except for the transfer of magnetic flux between the plunger 48 and the first stator core 36, which are opposed to each other via a minute gap, and also between the plunger 48 and the second stator core 40. That is, the magnetic flux can be transferred by the portion where the magnetic materials are in surface contact with each other). Therefore, the magnetic circuit of the solenoid 33 can secure high magnetic efficiency.

By the way, between the first stator core 36 and the second stator core 40 that form the main part of the solenoid 33, a non-magnetic ring that is located on the inner peripheral side of the mold coil 34 (coil 34A) and is a non-magnetic member. 44 is provided. The non-magnetic ring 44 is brazed between the first and second fixed iron cores (first and second stator cores 36 and 40) so as to increase the magnetic flux density of the magnetic circuit with respect to the movable iron core (plunger 48). It is joined by portions 45 and 46. However, when the non-magnetic member (non-magnetic ring 44) is machined after joining (for example, the inner peripheral surface is machined), the magnetic characteristics change due to the machining strain at this time, and the non-magnetic member is magnetized. There is a problem that it is easy to be magnetized.

Therefore, in the present embodiment, the non-magnetic ring 44 made of a non-magnetic material such as austenitic stainless steel is vertically formed from both ends of the thick-walled cylinder portion 44A in the middle in the axial direction and both ends of the thick-walled cylinder portion 44A. The protruding first and second fitting cylinders 44B and 44C form a stepped cylindrical integral body. The inner diameter dimension D1 of the non-magnetic ring 44 is larger than the inner diameters of the first and second stator cores 36 and 40.

That is, the non-magnetic ring 44 has an inner diameter of the non-magnetic ring 44 (that is, a thick cylinder portion 44A) in a state where the first stator core 36 and the second stator core 40 are joined by brazing portions 45 and 46. As shown in FIG. 4, the dimension D1) is formed so as to be larger than the inner diameter of the first stator core 36 and larger than the inner diameter of the second stator core 40 (that is, the radial dimension of the recessed portion 40D). There is.

Therefore, a plunger 48 as a movable iron core is axially placed on the inner peripheral side of the first and second stator cores 36 and 40 (first and second fixed iron cores) and the non-magnetic ring 44 (non-magnetic member). It can be arranged so as to be movable. That is, since the plunger 48 can be arranged inside the non-magnetic ring 44 with a gap, the non-magnetic ring 44 is machined after being joined to the first and second stator cores 36 and 40 (for example, the inner peripheral surface is machined). ), And the magnetic properties of the non-magnetic ring 44 do not change due to thermal influence, strain, or the like.

In this case, the non-magnetic ring 44 is a non-magnetic member made of austenitic stainless steel, and the non-magnetic ring 44 is joined between the first stator core 36 and the second stator core 40 by brazing portions 45 and 46. When this is done, brazing is performed using pure copper brazing (brazing material) or the like. That is, in austenitic stainless steel, for example, by performing a solid solution heat treatment of heat treatment at 1000 ° C. or higher, work-induced martensite can be removed and the crystal structure can be restored to the ideal face-centered cubic structure as a non-magnetic material. can.

In general, when distortion occurs due to deep drawing or cutting of austenitic stainless steel parts, which are non-magnetic materials, the material produces work-induced martensite, and some crystal structures are ideal surfaces as non-magnetic materials. It transforms into a body-centered cubic structure instead of a face-centered cubic structure, resulting in the property that the non-magnetic material is easily magnetized. However, the work-induced martensite of the austenitic stainless steel is removed by heat treatment at 1000 ° C. or higher, and the structure returns to the ideal face-centered cubic structure again. This process is called solution heat treatment.

Therefore, in the present embodiment, pure copper brazing is selected as the brazing material having a brazing temperature of 1000 ° C. or higher, and the brazing portions 45 and 46 perform a treatment that combines brazing and solidification heat treatment. The non-magnetic ring 44 joined between the second stator cores 36 and 40 can return the crystal structure to an ideal face-centered cubic structure as a non-magnetic material. Moreover, since the non-magnetic ring 44 is press-fitted between the first and second stator cores 36 and 40 and abutted against each other, thermal deformation due to high temperature during brazing is suppressed, and the purpose is to correct the shape after brazing. It is not necessary to perform the brazing process, and the desired dimensions and shape can be maintained. The brazing material may be other than pure copper brazing as long as the brazing temperature is 1000 ° C. or higher. For example, brass brazing, nickel brazing, gold brazing, palladium brazing and the like may be used.

Thus, according to the present embodiment, it is possible to suppress changes in the characteristics of the non-magnetic ring 44 (non-magnetic member) due to thermal influence, strain, or the like, and between the first and second stator cores 36 and 40. The magnetic flux density passing through the non-magnetic ring 44 (non-magnetic member) can be maintained high. The magnetic circuit of the solenoid 33 is all magnetic except for the transfer of magnetic flux between the plunger 48 and the first stator core 36 facing each other through a minute gap, and also between the plunger 48 and the second stator core 40. Since the magnetic flux can be transferred in a state where they are in surface contact with each other, the magnetic circuit of the solenoid 33 can secure high magnetic efficiency.

Moreover, the first fitting cylinder portion 44B of the non-magnetic ring 44 is fitted to the small diameter cylinder portion 36A of the first stator core 36 from the outside, and both are joined by the brazing portion 45. Further, the second fitting cylinder portion 44C is fitted to the outer peripheral side of the cylinder portion 40A and the conical protrusion 40E of the second stator core 40, and both are joined by a brazing portion 46. Then, the brazing portions 45 and 46 are subjected to a brazing treatment of, for example, 1000 ° C. or higher using a brazing material made of pure copper brazing, whereby the non-magnetic ring 44 is attached to the first and second stator cores 36 and 40. On the other hand, they are joined and a quenching treatment is performed after the brazing treatment.

As described above, in the present embodiment, the first and second stator cores 36 and 40 and the non-magnetic ring 44 are configured as described above, and the brazing portions 45 and 46 are made of pure copper brazing material (brazing material). For example, by performing a brazing treatment at 1000 ° C. or higher, the three members of the first and second stator cores 36 and 40 and the non-magnetic ring 44 can be joined to each other in a shape satisfying the coaxiality, and the inner side can be joined. The pressure resistance strength against pressure oil can also be ensured.

Therefore, the solenoid 33 adopted in the present embodiment is the solenoid 33 used for the semi-ac (damping force adjusting shock absorber) for adjusting the opening / closing operation of the damping force adjusting valve 18, and the fixed iron core (first and second). Between the magnetic members (first and second stator cores 36, 40) as a means for providing a non-magnetic portion for the purpose of forming a magnetic path between the stator cores 36, 40) and the movable iron core (plunger 48). Joining the non-magnetic member (non-magnetic ring 44) with the brazing portions 45 and 46 can provide an optimum method for making it possible to cope with the high withstand voltage of the damping force adjusting valve 18.

That is, by setting the brazing temperature when joining the non-magnetic ring 44 between the first and second stator cores 36 and 40 to 1000 ° C. or higher as described above, it also serves as a solidification heat treatment and is generated by cutting. The work-induced martensite (body-centered cubic structure) can be removed, and a metal structure with an ideal face-centered cubic structure can be obtained as a magnetic property. Since the cutting process for the purpose of shape correction after brazing is not performed, the ideal metal structure as a non-magnetic material is maintained without causing processing-induced martensite, and thermal deformation in the brazing process is performed. The structure can be suppressed.

As a result, the non-magnetic ring 44 as the non-magnetic part becomes an ideal metal structure, excellent magnetic characteristics can be obtained, and the thrust of the solenoid 33 can be improved and the thrust waveform can be optimized. Moreover, the number of steps in manufacturing and manufacturing the solenoid 33 is reduced, and workability and productivity can be improved.

In the above embodiment, the second stator core 40 is provided with a cylindrical tubular portion 40A, an annular portion 40B, and a tubular fitting portion 40C projecting on one side in the axial direction as an example. I mentioned and explained. However, the present invention is not limited to this, for example, a cylinder in which a second fixed iron core (that is, a second stator core) is formed by a cylindrical cylinder portion 40A and an annular portion 40B and projects to one side in the axial direction. The shape of the fitting portion may be omitted or abolished.

Further, in the above-described embodiment, the case where the cover member 51 is formed of a magnetic material as a yoke has been described as an example. However, the present invention is not limited to this, and a cover member may be formed of, for example, a non-magnetic material, and a coil open type solenoid without a yoke may be used. Further, in the above-described embodiment, the case where the solenoid 33 is configured as a proportional solenoid has been described as an example. However, the present invention is not limited to this, and for example, it may be configured as an ON / OFF type solenoid.

Next, the invention included in the above embodiment will be described. That is, as the first aspect of the present invention, a cylinder in which a working fluid is sealed, a piston inserted into the cylinder and defining the inside of the cylinder into a rod side chamber and a bottom side chamber, and a piston connected to the piston. A piston rod extending to the outside of the cylinder, a flow path in which the working fluid flows due to the movement of the piston rod, and a damping force adjusting valve provided in the flow path and whose opening / closing operation is adjusted by a solenoid are provided. The solenoid is a damping force adjusting type shock absorber, and the solenoid has a coil that generates a magnetic force by energization, a first and second fixed iron cores provided on the inner peripheral side of the coil, and the first and second fixed iron cores. A non-magnetic member provided between the fixed iron cores of the above and integrally fixed to the first and second fixed iron cores by brazing, and the first and second fixed iron cores and the non-magnetic member. The shaft portion is provided with a movable iron core arranged on the inner peripheral side and provided so as to be movable in the axial direction, a shaft portion provided on the movable iron core, and first and second bushes for supporting the shaft portion. The valve body of the damping force adjusting valve is provided at the end of the second fixed iron core side, and the inner diameter of the non-magnetic member is larger than the inner diameter of the first and second fixed iron cores. It is characterized by having a diameter or a small diameter.

In the damping force adjusting shock absorber according to the second aspect of the present invention, in the first aspect, the non-magnetic member is a member made of austenitic stainless steel. Further, in the damping force adjusting shock absorber according to the third aspect of the present invention, in the first or second aspect, the non-magnetic member is the brazing material using a brazing material having a brazing temperature of 1000 degrees or more. It is attached. In the damping force adjusting shock absorber according to the fourth aspect of the present invention, in the third aspect, the non-magnetic member is brazed using a brazing material made of pure copper brazing material.

The solenoid according to the fifth aspect of the present invention is between a coil that generates a magnetic force by energization, first and second fixed iron cores provided on the inner peripheral side of the coil, and the first and second fixed iron cores. A non-magnetic member provided in the above and integrally fixed to the first and second fixed iron cores by brazing, and arranged on the inner peripheral side of the first and second fixed iron cores and the non-magnetic member. The first and second fixings are provided with a movable iron core provided so as to be movable in the axial direction, a shaft portion provided on the movable iron core, and first and second bushes for supporting the shaft portion. The inner diameter of the non-magnetic member is larger or smaller than the inner diameter of the iron core.

In the fifth aspect of the solenoid according to the sixth aspect of the present invention, the non-magnetic member is a member made of austenitic stainless steel. In the solenoid according to the seventh aspect of the present invention, in the fifth or sixth aspect, the non-magnetic member is brazed using a brazing material having a brazing temperature of 1000 degrees or higher. In the solenoid according to the eighth aspect of the present invention, in the seventh aspect, the non-magnetic member is brazed using a brazing material made of pure copper brazing material. In any of the fifth to eighth aspects, the solenoid according to the ninth aspect of the present invention defines an inner diameter portion that defines the inner diameter of the first and second fixed iron cores and an inner diameter portion that defines the inner diameter of the non-magnetic member. The inner diameter portion to be formed is characterized in that it is not machined after brazing.

A tenth aspect of the present invention is a cylinder in which a working fluid is sealed, a piston inserted into the cylinder and defining the inside of the cylinder into a rod side chamber and a bottom side chamber, and the cylinder connected to the piston. A damping force adjusting valve including a piston rod extending to the outside, a flow path in which the working fluid flows due to the movement of the piston rod, and a damping force adjusting valve provided in the flow path and whose opening / closing operation is adjusted by a solenoid. The solenoid is a force-adjustable shock absorber, and the solenoid has a coil that generates a magnetic force when energized, a first and second fixed iron cores provided on the inner peripheral side of the coil, and the first and second fixed iron cores. A non-magnetic member provided between the first and second fixed iron cores and integrally fixed to the first and second fixed iron cores by brazing, and the inner peripheral side of the first and second fixed iron cores and the non-magnetic member. The shaft is provided with a movable iron core arranged in the shaft and provided so as to be movable in the axial direction, a shaft portion provided on the inner peripheral side of the movable iron core, and first and second bushes for supporting the shaft portion. The valve body of the damping force adjusting valve is provided at the end of the portion on the side of the second fixed iron core, and the inner diameter portion defining the inner diameter of the non-magnetic member shall not be machined after brazing. It is characterized by.

The present invention is not limited to the above-described embodiment, and includes various modifications. For example, the above-described embodiment has been described in detail in order to explain the present invention in an easy-to-understand manner, and is not necessarily limited to the one including all the described configurations. Further, it is possible to replace a part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. Further, it is possible to add / delete / replace other configurations with respect to a part of the configurations of each embodiment.

The present application claims priority under Japanese Patent Application No. 2018-241220 filed on December 25, 2018. The entire disclosure, including the specification, claims, drawings, and abstract of Japanese Patent Application No. 2018-241220 filed December 25, 2018, is incorporated herein by reference in its entirety.

1 Hydraulic shock absorber (damping force adjustment type shock absorber) 4 Inner cylinder (cylinder) 5 Piston 8 Piston rod 17 Damping force adjusting device 18 Damping force adjusting valve 32 Pilot valve body (valve body) 33 Solenoid 34 Mold coil 34A Coil 36th 1 Solenoid core (1st fixed iron core) 37 Core lid 38 1st bush 40 2nd stator core (2nd fixed iron core) 40A Cylinder 41 2nd bush 44 Non-magnetic ring (non-magnetic member) 45, 46 Brazing part 48 Plunger (movable iron core) 49 Acting pin (shaft part) A Reservoir chamber B Rod side oil chamber (rod side chamber) C Bottom side oil chamber (bottom side chamber) D Ring oil chamber (flow path) D1 Dimensions (non-) Inner diameter of magnetic member)

In order to solve the above-mentioned problems, one embodiment of the present invention includes a cylinder in which a working fluid is sealed, a piston that is inserted into the cylinder and defines the inside of the cylinder into a rod side chamber and a bottom side chamber, and the above. A piston rod connected to a piston and extending to the outside of the cylinder, a flow path in which the working fluid flows due to the movement of the piston rod, and a damping force adjusting valve provided in the flow path whose opening / closing operation is adjusted by a solenoid. The solenoid is a damping force adjusting type shock absorber comprising A non-magnetic member provided between the first and second fixed iron cores, which is integrally fixed to the first and second fixed iron cores by brazing and which is not processed after the brazing, and the above-mentioned A movable iron core arranged on the inner peripheral side of the first and second fixed iron cores and the non-magnetic member and provided so as to be movable in the axial direction, a shaft portion provided on the movable iron core, and a first support for the shaft portion. A valve body of the damping force adjusting valve is provided at an end of the shaft portion on the side of the second fixed iron core, and the first and second bushes are provided. The inner diameter of the non-magnetic member is larger or smaller than the inner diameter.

Further, the solenoid according to the embodiment of the present invention includes a coil that generates a magnetic force by energization, first and second fixed iron cores provided on the inner peripheral side of the coil, and the first and second fixed iron cores. A non-magnetic member provided between the above and integrally fixed to the first and second fixed iron cores by brazing and not processed after the brazing, and the first and second fixings. A movable iron core arranged on the inner peripheral side of the iron core and the non-magnetic member and provided so as to be movable in the axial direction, a shaft portion provided on the movable iron core, and first and second bushes for supporting the shaft portion. , And the inner diameter of the non-magnetic member is larger or smaller than the inner diameter of the first and second fixed iron cores.

Claims (10)

It is a damping force adjustment type shock absorber, and the damping force adjustment type shock absorber is
Cylinder in which working fluid is sealed and
A piston that is inserted into the cylinder and defines the inside of the cylinder into a rod side chamber and a bottom side chamber.
A piston rod that is connected to the piston and extends to the outside of the cylinder,
A flow path in which the working fluid flows due to the movement of the piston rod, and
A damping force adjusting valve provided in the flow path and whose opening / closing operation is adjusted by a solenoid is provided.
The solenoid is
A coil that generates a magnetic force when energized,
The first and second fixed iron cores provided on the inner peripheral side of the coil and
A non-magnetic member provided between the first and second fixed iron cores and integrally fixed to the first and second fixed iron cores by brazing.
A movable iron core arranged on the inner peripheral side of the first and second fixed iron cores and the non-magnetic member and provided so as to be movable in the axial direction, and
The shaft portion provided on the movable iron core and
A first and second bushes that support the shaft portion are provided.
A valve body of the damping force adjusting valve is provided at the end of the shaft portion on the side of the second fixed iron core.
A damping force adjusting shock absorber characterized in that the inner diameter of the non-magnetic member is larger or smaller than the inner diameter of the first and second fixed iron cores. In the damping force adjustment type shock absorber according to claim 1,
The non-magnetic member is a damping force adjusting shock absorber made of austenitic stainless steel. In the damping force adjusting shock absorber according to claim 1 or 2.
The non-magnetic member is a damping force adjusting shock absorber formed by brazing using a brazing material having a brazing temperature of 1000 degrees or higher. In the damping force adjustment type shock absorber according to claim 3,
The non-magnetic member is a damping force adjusting shock absorber made by brazing using a brazing material made of pure copper brazing material. A coil that generates a magnetic force when energized,
The first and second fixed iron cores provided on the inner peripheral side of the coil and
A non-magnetic member provided between the first and second fixed iron cores and integrally fixed to the first and second fixed iron cores by brazing.
A movable iron core arranged on the inner peripheral side of the first and second fixed iron cores and the non-magnetic member and provided so as to be movable in the axial direction, and
The shaft portion provided on the movable iron core and
A first and second bushes that support the shaft portion are provided.
A solenoid characterized in that the inner diameter of the non-magnetic member is larger or smaller than the inner diameter of the first and second fixed iron cores. In the solenoid according to claim 5,
The non-magnetic member is a solenoid that is a member made of austenitic stainless steel. In the solenoid according to claim 5 or 6.
The non-magnetic member is a solenoid formed by brazing using a brazing material having a brazing temperature of 1000 degrees or higher. In the solenoid according to claim 7,
The non-magnetic member is a solenoid formed by brazing using a brazing material made of pure copper brazing material. In the solenoid according to any one of claims 5 to 8.
A solenoid characterized in that the inner diameter portion that defines the inner diameter of the first and second fixed iron cores and the inner diameter portion that defines the inner diameter of the non-magnetic member are not machined after brazing. It is a damping force adjustment type shock absorber, and the damping force adjustment type shock absorber is
Cylinder in which working fluid is sealed and
A piston that is inserted into the cylinder and defines the inside of the cylinder into a rod side chamber and a bottom side chamber.
A piston rod that is connected to the piston and extends to the outside of the cylinder,
A flow path in which the working fluid flows due to the movement of the piston rod, and
A damping force adjusting valve provided in the flow path and whose opening / closing operation is adjusted by a solenoid is provided.
The solenoid is
A coil that generates a magnetic force when energized,
The first and second fixed iron cores provided on the inner peripheral side of the coil and
A non-magnetic member provided between the first and second fixed iron cores and integrally fixed to the first and second fixed iron cores by brazing.
A movable iron core arranged on the inner peripheral side of the first and second fixed iron cores and the non-magnetic member and provided so as to be movable in the axial direction, and
A shaft portion provided on the inner peripheral side of the movable iron core and
A first and second bushes that support the shaft portion are provided.
A valve body of the damping force adjusting valve is provided at the end of the shaft portion on the side of the second fixed iron core.
The damping force adjusting type shock absorber is characterized in that the inner diameter portion that defines the inner diameter of the non-magnetic member is not machined after brazing.

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