JP4104788B2 - Manufacturing method of solenoid valve - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a solenoid valve.
[0002]
[Prior art]
2. Description of the Related Art An electromagnetic valve that performs hydraulic pressure control by electromagnetically attracting a plunger according to a current value applied to a coil of an electromagnetic unit and sliding a spool of a spool valve unit is well known. Conventionally, as such an electromagnetic valve, what is shown, for example in FIG. 6 is known.
[0003]
The electromagnetic part 72 of the electromagnetic valve 71 includes a cover 73, a coil 74, a plunger 75, a core 76, a shaft 77, and the like. An oil sump chamber 78 that accommodates the base end portion of the shaft 77 is formed in the cover 73 to which the coil 74 is attached. A sliding chamber 79 having a diameter larger than that of the oil reservoir chamber 78 is formed so as to continue to the oil reservoir chamber 78. A hollow core 76 is disposed adjacent to the sliding chamber 79. One end surface of the core 76 (hereinafter referred to as a joining surface 80) is joined to the valve sleeve 82 of the spool valve portion 81. The shaft 77 is fixed to the plunger 75 so as to transmit the displacement of the plunger 75 to the spool 83 disposed on the opposite side across the core 76, and is in contact with the spool 83 through a through hole 84 provided in the core 76. . Further, in order to impart damping to the operation of the plunger 75 of the electromagnetic part 72, lubricating oil is always stored in the electromagnetic part 72.
[0004]
A bush 85 is provided on the inner peripheral surface of the through hole 84 of the core 76 and the oil reservoir chamber 78 of the cover 73, and the shaft 77 is supported by the core 76 and the cover 73 via the bush 85. A pair of communication grooves 86 extending in the length direction are provided on the inner peripheral surfaces of the core 76 and the cover 73.
[0005]
Thereby, when the plunger 75 slides, the lubricating oil flows smoothly through the core 76 and the communication groove 86 of the oil reservoir chamber 78, and the response of the shaft 77 is improved.
[0006]
[Problems to be solved by the invention]
By the way, in the manufacturing process of the electromagnetic valve 71, in order to increase the dimensional accuracy of each member, the entire surface of the cover 73 and the joint surface 80 of the core 76 with the valve sleeve 82 are ground using a milling machine or the like. As a result, conventionally, when the joint surface 80 of the core 76 with the valve sleeve 82 and the end surface on the opening side of the communication groove 86 of the cover 73 are ground, the opening of the communication groove 86 is located on the same plane. The opening portion of the communication groove 86 is also ground intermittently. At the time of this grinding process, as shown in FIGS. 7A and 7B, burrs 87 may occur at the opening peripheral edge of the communication groove 86 of the cover and the core to block the opening of the communication groove 86. In this state, since a smooth flow of lubricating oil cannot be expected, the burr 87 is removed with a rotating brush or the like. However, since the generated burr 87 is large and the communication groove 86 has a small diameter, there is a problem in that the brush does not act effectively, deburring cannot be performed, and removal work takes a long time.
[0007]
The objective of this invention is providing the manufacturing method of the solenoid valve which can remove easily the burr | flash which generate | occur | produced in the opening periphery of the communicating groove | channel.
[0008]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, an invention according to claim 1 is provided with a plunger that is movable by excitation of a coil, a shaft that applies a load to the valve body by the plunger, and the shaft is inserted into the shaft. A support member having an insertion space having an inner peripheral surface that supports the shaft slidably along the center direction, and a communication groove is formed on the inner peripheral surface along the axial direction. Is a passage of a lubricating oil that communicates with the space in the support member or other valve internal space, the opening cross-sectional area of the insertion space of the support member is provided on the end surface of the communication groove in the support member. A burr relief recess having a cross-sectional area smaller than the cross-sectional area of the inner peripheral surface of the cylindrical portion on which the plunger is slid and extending outward in the radial direction from the communication groove is formed . Forging the burr relief recess After forming in, except the burr relief recess by grinding the surface of the support member, and summarized in that the removal of burrs generated in the periphery of the concave relief burr by the surface grinding.
[0010]
It invention according to claim 2, in the manufacturing method of the solenoid valve according to claim 1, wherein the support member is a cover member for supporting one end of the shaft, the insertion space is a support hole of the bottom Is the gist.
[0011]
According to a third aspect of the present invention, in the method for manufacturing an electromagnetic valve according to the first aspect, the support member is a core member in which a coil is disposed in an external space, and the insertion space is a through hole of the core member. It is a summary.
[0012]
(Function)
According to the first aspect of the present invention, since the burr relief recess is formed on the end surface on the opening side of the communication groove, even if the end surface on the opening side of the communication groove in the support member is ground, it is intermittently connected to the opening of the communication groove. Does not grind.
[0013]
In addition , since a mold in which a burr relief recess is formed in advance and the burr relief recess is formed by forging, the burr relief recess is easily formed.
[0014]
According to the invention 請 Motomeko 2, in addition to the operation of claim 1, burr relief recess is formed in the cross-sectional area greater than the cross-sectional area of the opening of a bottomed support hole of the cover member.
[0015]
According to the invention of claim 3 , in addition to the action of claim 1 , the burr relief recess is formed in a cross-sectional area larger than the opening cross-sectional area of the through hole of the core member.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
Hereinafter, an embodiment embodying the present invention will be described with reference to FIGS.
[0017]
As shown in FIG. 1, the electromagnetic valve 11 includes a spool valve portion 12 and an electromagnetic portion 13.
The electromagnetic part 13 includes a cover 14 as a support member and a cover member, a core 15 as a support member and a core member, a coil 16, a plunger 17, a shaft 18, and the like. A spool 20 or the like as a valve body is provided.
[0018]
The cover 14 made of a magnetic body has a bottomed cylindrical outer cylindrical portion 21 and an inner cylinder that is smaller in diameter than the inner cylindrical portion 21 and shorter in the axial direction than the outer cylindrical portion 21. It is comprised from the shape part 22. FIG. The outer cylindrical portion 21 and the inner cylindrical portion 22 are formed on the same axis, and both the cylindrical portions 21 and 22 are integrally formed so as to be continuous at the bottom. An insertion space and a first oil sump chamber 23 as a bottomed support hole are formed at the base end of the space in the inner cylindrical portion 22. A bobbin 24 around which the coil 16 is wound is fitted and fixed in a cylindrical space formed by the inner cylindrical portion 22 and the outer cylindrical portion 21. Further, one end of the coil 16 is disposed so as to protrude from the inner cylindrical portion 22.
[0019]
The core 15 has a flange 26, and is joined to the distal end surface of the outer cylindrical portion 21 by the flange 26. The core 15 is made of a substantially cylindrical magnetic body, and a through hole 25 serving as an insertion space concentric with the first oil sump chamber 23 is formed in the axial center thereof. A bobbin 24 around which the coil 16 is wound is fitted on the outer peripheral surface of the core 15. Further, the bobbin 24 is brought into contact with a flange 26 formed on a side end portion of the core 15 through a filter 27. A concave yoke portion 15a is formed at the tip of the core 15 on the first oil reservoir chamber 23 side.
[0020]
By the inner cylindrical portion 22 and the yoke portion 15 a of the core 15, a sliding chamber 28 having a larger diameter than the first oil reservoir chamber 23 is formed in a substantially columnar shape so as to be continuous with the first oil reservoir chamber 23. The sliding chamber 28 includes a first end surface 28a formed in the inner cylindrical portion 22 and a second end surface 28b formed in the yoke portion 15a. In the sliding chamber 28, the plunger 17 made of a magnetic material is separated from the yoke portion 15 a that defines the sliding chamber 28 and the inner peripheral surface of the inner cylindrical portion 22 as a cylindrical portion via a slight interval. It is slidably arranged. A shaft 18 made of a non-magnetic material is passed through and fixed to the axis of the plunger 17. One end of the shaft 18 is slidably inserted into the through-hole 25 of the core 15 via the bush 29b, and protrudes from the end surface of the core 15 (hereinafter referred to as a joining surface 30). The other end of the shaft 18 is slidably inserted into the first oil sump chamber 23 via a bush 29a.
[0021]
A valve sleeve 19 is disposed on the joint surface 30 side of the core 15. The valve sleeve 19 is crimped to the electromagnetic portion 13 by caulking the end portion of the outer cylindrical portion 21 of the cover 14 with the flange portion 34 formed on the side end portion being joined to the flange 26 of the core 15. They are integrally connected to each other. The valve sleeve 19 is provided with a spool hole 31 extending in the axial direction and a plurality of ports 32 formed at intervals in the axial direction. An annular groove 33 is formed on the inner peripheral surface of the spool hole 31 corresponding to each port 32. A lid plug 36 that closes the open end of the spool hole 31 is screwed to the anti-electromagnetic part 13 side of the valve sleeve 19.
[0022]
In the spool hole 31, a spool 20 having a plurality of land portions 35a, 35b, and 35c is slidably disposed. The land portions 35a, 35b, and 35c are a small-diameter land portion 35a, a medium-diameter land portion 35b, and a large-diameter land portion 35c in order from the electromagnetic portion 13 side. The tip of the spool 20 on the electromagnetic part 13 side is formed in a hemispherical shape, and is in contact with the tip of the shaft 18. A spring 37 for biasing the spool 20 in the direction of the electromagnetic part 13 is inserted between the lid plug 36 and the spool 20.
[0023]
A second oil reservoir chamber 38 surrounded by the valve sleeve 19, the spool 20 and the core 15 is formed at the end of the spool hole 31 on the electromagnetic part 13 side. The second oil reservoir chamber 38 is formed to have substantially the same diameter as the large-diameter land portion 35 c of the spool 20. Lubricating oil is always stored in the electromagnetic part 13 and the spool valve part 12, and the valve sleeve 19 is provided with a communication hole (not shown) for draining the lubricating oil filled in the second oil reservoir chamber 38. It has been.
[0024]
As shown in FIGS. 2 (a) and 2 (b), the flow of the lubricating oil in the first oil sump chamber 23 due to the movement of the shaft 18 can be smoothly performed on the inner peripheral surface of the first oil sump chamber 23. A pair of communication grooves 39a is provided for this purpose. The communication grooves 39a are formed in a U-shaped cross section extending in parallel to each other in the axial direction and facing in the radial direction. The first end surface 28a of the sliding chamber 28 is provided with a step 40a as a burr relief recess having a circular side cross section. The step portion 40a is formed so as to have a cross-sectional area larger than the opening cross-sectional area of the first oil sump chamber 23 and to extend radially outward from the communication groove 39a.
[0025]
On the other hand, as shown in FIGS. 3 (a) and 3 (b), on the inner peripheral surface of the through hole 25 of the core 15, lubrication from the sliding chamber 28 to the second oil sump chamber 38 due to the movement of the shaft 18 and vice versa. A pair of communication grooves 39b are provided to enable smooth oil flow. A stepped portion 40b having a circular side cross section is provided on the joint surface 30 of the core 15 corresponding to the open end of the communication groove 39b. The stepped portion 40b is formed so as to have a cross-sectional area larger than the opening cross-sectional area of the through hole 25 and to extend radially outward from the communication groove 39b.
[0026]
Next, the operation of the electromagnetic valve 11 configured as described above will be described.
In the case of manufacturing the cover 14 of the electromagnetic unit 13, a mold in which the stepped portions 40 a and 40 b are formed in advance is prepared, and the cover 14 is formed by forging. Thereafter, the first oil reservoir chamber 23 and the communication groove 39a are formed by cutting. After forging, the surface of the cover 14 is ground by a milling machine or the like. When the space in the inner cylindrical portion 22 is ground, the stepped portion 40a is not milled, and therefore, it is not intermittently ground to the mouth of the communication groove 39a. Even if burrs are generated on the periphery of the stepped portion 40a due to grinding, the inner diameter of the stepped portion 40a is large, unlike the communication groove 39a, and therefore it can be easily removed with a rotating brush or the like.
[0027]
On the other hand, when the core 15 is manufactured, as in the case of the cover 14, a mold in which the stepped portion 40 b is formed in advance is prepared, and the core 15 is formed by forging. Thereafter, the through hole 25 and the communication groove 39b are formed by cutting. Then, the joint surface 30 is ground by a milling machine or the like. When the joint surface 30 of the core 15 is ground, the stepped portion 40b is not milled, and therefore, it is not intermittently ground to the mouth of the communication groove 39b. Even if burrs are generated at the periphery of the stepped portion 40b of the joining surface 30, the inner diameter of the stepped portion 40b is large, unlike the communication groove 39b, so that it can be easily removed with a rotating brush or the like as in the case of the cover 14. Is done.
[0028]
When an excitation current is supplied from a power supply control unit (not shown) to the coil 16 of the electromagnetic valve 11 in which the step portions 40a and 40b are formed at the open ends of the communication grooves 39a and 39b as described above, the plunger 17 is moved to the core by electromagnetic attraction force It is drawn toward 15 yoke portions 15a. Then, the accompanying displacement of the shaft 18 is transmitted to the spool 20, and the spool 20 is displaced against the elastic force of the spring 37. As a result, the opening degree of the predetermined port 32 is changed.
[0029]
During the above operation, the plunger 17 is displaced toward the second end face 28 b, so that the volume of the space S surrounded by the shaft 18 and the bush 29 a of the first oil reservoir 23 becomes the second oil reservoir chamber of the shaft 18. The volume is increased by a volume corresponding to the indentation into 38. As a result, the pressure in the space S of the first oil sump chamber 23 decreases, so that the lubricating oil in the second oil sump chamber 38 flows between the communication groove 39b of the core 15, the plunger 17 and the yoke portion 15a, and the inner cylindrical portion 22. And through the communication groove 39a of the first oil sump chamber 23, the air is sucked into the space S of the first oil sump chamber 23.
[0030]
Conversely, when energization is stopped and the plunger 17 is displaced toward the first end face 28 a by the elastic force of the spring 37, the volume of the space S of the first oil reservoir 23 is equal to the first oil reservoir 23 of the shaft 18. Is reduced by a volume corresponding to the amount pushed into the space S. As a result, the pressure in the space S of the first oil sump chamber 23 rises, and the lubricating oil passes through the communication groove 39a of the first oil sump chamber 23, the distance between the plunger 17 and the yoke portion 15a, the inner cylindrical portion 22, and the core. It passes through the 15 communication grooves 39 b and is pushed out into the second oil sump chamber 38. Here, since there is no burr on the opening periphery of the communication grooves 39a and 39b, the lubricating oil flows smoothly.
[0031]
According to the above embodiment, the following features can be obtained.
(1) In the above embodiment, since the step portions 40a and 40b are provided on the first end surface 28a of the sliding chamber 28 and the joint surface 30 of the core 15, the surface of the cover 14 and the joint surface 30 of the core 15 are provided. Even if the grinding is performed, the openings of the communication grooves 39a and 39b are not intermittently ground, and burrs are not generated at the opening peripheral edges of the communication grooves 39a and 39b.
[0032]
(2) In the above embodiment, the step portions 40a and 40b are prepared by forging a mold in which the step portions 40a and 40b are formed in advance, so that the step portions 40a and 40b are easily formed. Can be formed.
[0033]
(3) In the above embodiment, even if the surface of the cover 14 and the joint surface 30 of the core 15 are ground, burrs can be formed only at the peripheral edges of the stepped portions 40a and 40b, and even if burrs are generated, the stepped portions 40a and 40b. Unlike the communication grooves 39a and 39b, the inner diameter is large, so that the removal operation can be performed easily.
(Second Embodiment)
Next, a second embodiment of the present invention will be described in detail based on FIG.
[0034]
In the following embodiments, the same or corresponding components as those of the embodiments are assigned the same reference numerals and description thereof is omitted.
In the present embodiment, as shown in FIG. 4, the cover 14 of the electromagnetic part 13 is formed in a cylindrical shape, and the opening part of the cover 14 on the side opposite to the spool valve part 12 is closed by a closing plate 41. Between the closing plate 41 and the open end of the cover 14, the peripheral edge of the disc spring 42 is clamped and fixed. The end of the plunger 17 is attached and fixed to the center of the disc spring 42 and supported.
[0035]
The plunger 17 is loosely fitted into a hollow hole 43 formed in the cover 14 with a minute gap 44. One end of the shaft 18 slidably inserted into the through hole 25 of the core 15 via the bush 29 b is integrally connected to the plunger 17. A third oil sump chamber 45 is formed between the plunger 17 and the closing plate 41. Since the disk spring 42 has a shape in which the outer peripheral portion and the center are connected by a plurality of beams, the lubricating oil on the closing plate 41 side and the lubricating oil on the shaft 18 side communicate with each other via the disk spring 42. It has become.
[0036]
The spool 20 of the spool valve portion 12 is formed with three large-diameter land portions 35d, 35e, and 35f and two small-diameter land portions 35g and 35h at a predetermined interval. The degree of opening is controlled.
[0037]
In the electromagnetic valve 11 of the present embodiment, a pair of communication grooves 39 b is provided only on the inner periphery of the through hole 25 of the core 15. And the step part 40b is provided in the joint surface 30 of the core 15 which hits the opening end of the communicating groove 39b. In the present embodiment, only the core 15 is a support member for the shaft 18, and only the through hole 25 of the core 15 is an insertion space.
[0038]
Next, the operation of this embodiment will be described.
In the present embodiment, a mold in which the stepped portion 40b is formed in advance is prepared only for the core 15, and the core 15 is formed by forging. Thereafter, the joint surface 30 of the core 15 is ground by a milling machine or the like (not shown). Here, since the step portion 40b is provided, even if the core joint surface is ground, it is not intermittently ground to the opening of the communication groove 39b, and no burr is generated at the opening periphery of the communication groove 39b. Even if burrs are generated at the periphery of the stepped portion 40b, the inner diameter of the stepped portion 40b is large, unlike the communication groove 39b, and therefore it can be easily removed with a rotating brush or the like as in the case of the cover 14.
[0039]
When the exciting current from the power supply control unit is applied to the coil 16, the plunger 17 is attracted toward the yoke portion 15a of the core 15 against the elastic force of the disk spring 42 by the electromagnetic attractive force, and the shaft that accompanies it. Eighteen displacements are transmitted to the spool 20.
[0040]
During the above operation, the plunger 17 and the shaft 18 are displaced toward the spool valve portion 12 against the elastic force of the spring 37 and the disc spring 42, so that the plunger 17 and the closing plate 41 of the third oil sump chamber 45 are displaced. The volume of the enclosed space V increases by a volume corresponding to the displacement of the plunger 17. As a result, the pressure in the space V of the third oil reservoir chamber 45 decreases, so that the lubricating oil in the second oil reservoir chamber 38 passes through the communication groove 39b and the gap 44 of the core 15 and passes through the space of the third oil reservoir chamber 45. V is aspirated.
[0041]
On the contrary, when the energization is stopped and the shaft 18 and the plunger 17 are displaced toward the closing plate 41 by the elastic force of the spring 37 and the disk spring 42, the volume of the space V of the third oil sump chamber 45 is equal to the displacement of the plunger 17. Is reduced by a volume corresponding to. For this reason, the pressure in the space V of the third oil sump chamber 45 rises, and the lubricating oil is pushed out to the second oil sump chamber 38 through the gap 44 and the communication groove 39b. Here, since there is no burr at the opening periphery of the communication groove 39b, the lubricating oil flows smoothly.
[0042]
Therefore, in this embodiment, since the joint surface 30 of the core 15 is provided with the step portion 40b, even if the joint surface 30 of the core 15 is ground, it is ground intermittently to the mouth of the communication groove 39b. No burrs are generated on the peripheral edge of the opening of the communication groove 39b. In addition, since the step portion 40b is prepared by forging a mold in which the step portion 40b is formed in advance and formed by forging, the step portion 40b can be easily formed. Moreover, even if the joint surface 30 of the core 15 is ground, burrs can be formed only at the periphery of the stepped portion 40b, and even if burrs are generated, the inner diameter of the stepped portion 40b is large, unlike the communication groove 39b. Easy removal work.
[0043]
In addition, you may change this embodiment as follows.
(A) The step portions 40a and 40b in the first and second embodiments may be arcuate recesses 40c as shown in FIG. (In FIG. 5, only the recess 40c in the cover 14 is shown.)
(B) In the first and second embodiments, a mold in which the step portions 40a and 40b are formed in advance is prepared, and the step portions 40a and 40b of the cover 14 or the core 15 are formed by forging. In the cover 14, the step portion 40 a may be ground by a milling machine or the like, and then the first oil reservoir 23 and the communication groove 39 a may be provided to grind the surface of the cover 14. On the other hand, in the core 15, the stepped portion 40 b may be ground by a milling machine or the like, the through hole 25 and the communication groove 39 b may be provided, and the joint surface 30 may be ground.
[0044]
Next, technical ideas that can be grasped from the above embodiment and other examples will be described below together with their effects.
(1) In the said insertion space, the bush is arrange | positioned between the internal peripheral surfaces of the supporting member of a shaft, The manufacturing method of the solenoid valve of any one of Claim 1 thru | or 3 characterized by the above-mentioned. Since the bush is a low-friction material and is low in cost, a solenoid valve can be manufactured at a lower cost than using, for example, a brass bearing gauge as a bearing.
[0045]
【The invention's effect】
As described above in detail, according to the first aspect of the present invention, it is possible to prevent burrs from being generated at the opening periphery of the communication groove.
[0046]
Moreover , the burr relief part can be easily formed by forging .
[0047]
According to the second aspect of the present invention, in addition to the first aspect, it is possible to prevent the occurrence of burrs on the opening peripheral edge of the communication groove formed on the inner peripheral surface of the support hole of the cover member.
[0048]
According to the invention of claim 3 , in addition to claim 1, it is possible to prevent the occurrence of burrs on the opening peripheral edge of the communication groove formed on the inner peripheral surface of the through hole of the core member.
[Brief description of the drawings]
FIG. 1 is a front sectional view of a solenoid valve according to a first embodiment.
FIG. 2A is an enlarged front sectional view of a main part in the first embodiment, and FIG. 2B is an enlarged sectional view of a main part of the AA line in FIG.
FIG. 3A is an enlarged front sectional view of a main part in the first embodiment, and FIG.
FIG. 4 is a front sectional view of a solenoid valve according to a second embodiment.
FIG. 5 is an enlarged front sectional view of a main part in another embodiment.
FIG. 6 is a front sectional view of a conventional solenoid valve.
FIG. 7A is an enlarged cross-sectional view of a main part of a conventional solenoid valve before assembly, and FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 ... Solenoid valve, 14 ... Cover (support member, cover member), 15 ... Core (support member, core member), 16 ... Coil, 17 ... Plunger, 18 ... Shaft, 20 ... Spool (valve body), 23 ... No. 1 oil sump chamber (insertion space, support hole), 25 ... through hole (insertion space), 28a ... first end face (end face) 30 ... joint face (end face), 39a, 39b ... communication groove, 40a, 40b ... step part (Burr relief recess).

Claims (3)

A plunger that is movable by excitation of a coil is provided, and a shaft that applies a load to the valve body by the plunger, and an inner peripheral surface that supports the shaft slidably along the axial center direction of the shaft is inserted. And a support member having an insertion space, and a communication groove is formed in the inner peripheral surface along the axial direction, and the communication groove communicates with a space in the support member or another valve internal space. In the solenoid valve used as oil passage,
The end surface on the opening side of the communication groove in the support member has a cross-sectional area that is larger than the opening cross-sectional area of the insertion space of the support member and smaller than the cross-sectional area of the inner peripheral surface of the cylindrical portion on which the plunger slides. And a burr relief recess that extends radially outward from the communication groove is formed ,
After the burr relief recess of the support member is formed by forging, the surface of the support member is ground except for the burr relief recess, and the burr generated on the periphery of the burr relief recess by the surface grinding is removed . Manufacturing method . The method of manufacturing an electromagnetic valve according to claim 1, wherein the support member is a cover member that supports one end of the shaft, and the insertion space is a bottomed support hole . The method of manufacturing an electromagnetic valve according to claim 1, wherein the support member is a core member in which a coil is disposed in an external space, and the insertion space is a through hole of the core member .

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