JP4524927B2 - Caulking method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a caulking method for integrally connecting a shaft body and a cylindrical body.
[0002]
[Prior art]
Conventionally, for example, a method for manufacturing a solenoid valve disclosed in Japanese Patent Application Laid-Open No. 64-46080 has been known. In this conventional manufacturing method, a shaft (sometimes referred to as a rod), which is a component of a solenoid valve, and a plunger are integrally connected by caulking. Specifically, an annular groove is formed on the outer periphery of the shaft, and plating is applied to the shaft to deposit a thicker plating layer at the corner of the groove than the other portions. On the other hand, the plunger is provided with an insertion hole through which the shaft is inserted. When a plated shaft is inserted into the insertion hole, a fastening margin is generated between the outer peripheral portion of the thick plated layer at the corner of the concave groove and the inner peripheral surface of the insertion hole, and the shaft is press-fitted into the plunger. By this press-fitting, the shaft is temporarily fixed at a predetermined position with respect to the plunger, and the plunger is deformed by pressing and caulking a pressing portion (a portion corresponding to the concave groove) provided on the outer periphery of the plunger, thereby strengthening the shaft. Can be fixed to.
[0003]
[Problems to be solved by the invention]
In the conventional method, the crimping process is performed after the shaft is temporarily fixed to a predetermined position of the plunger by press-fitting. By the way, when the shaft is press-fitted into the plunger, the outer peripheral surface of the thick plating layer and the inner peripheral surface of the insertion hole are in contact with each other over almost the entire periphery. When the plunger in this state is pressed from the outer periphery at two opposing points, the plunger insertion hole is deformed into an ellipse having a short direction in the pressing direction, that is, the diameter decreases in the pressing direction and expands in the direction perpendicular to the pressing direction. Since the outer peripheral surface and the inner peripheral surface are in contact with each other only around the pressing portion, the shaft is supported by the plunger at two points.
[0004]
For this reason, the caulking process strengthens the retaining strength in the axial direction of the shaft, but the contact portion between the outer peripheral surface and the inner peripheral surface is substantially two points. Makes it easier to swing. Such shaft oscillation can be prevented by caulking the pressing portion from two points to four points, for example, in the direction perpendicular to the pressing direction. In this case, however, productivity decreases as the number of caulking points increases. .
[0005]
SUMMARY OF THE INVENTION
The present invention has been made to cope with the above-described problems, and its purpose is to ensure the retaining strength (coupling force) of the shaft body (or the shaft to the plunger) with respect to the cylindrical body and the shaft with respect to the cylindrical body. An object of the present invention is to provide a caulking method for preventing body swinging.
[0006]
The characteristic of the present invention (characteristic of the invention according to claim 1) is that the shaft body is caulked from the outer periphery of the cylindrical body toward the shaft body in a state where the shaft body is inserted into the insertion hole of the cylindrical body. In the caulking method for integrally connecting the shaft body and the cylindrical body, the insertion of the shaft body and the cylindrical body is a gap fitting including a gap zero, and the two-surface width portion formed in the cylindrical body A pair of punches that press and squeeze are provided in an offset state in which the respective central axes are not on the same line, and pass through the axial center of the cylindrical body in the two-surface width portion formed in the cylindrical body by to facilities caulking to be asymmetrical with respect to the axis, a line at a site other than the caulking portion, the inner peripheral surface of the insertion hole of the tubular body and the outer peripheral surface of the shaft body at least axially It is in touching.
[0007]
According to this, the shaft body and the cylindrical body are integrated by line contact in at least the axial direction between the crimped portion of the cylindrical body, the outer peripheral surface of the shaft body and the inner peripheral surface of the insertion hole of the cylindrical body. Connected. As a result, the shaft body is secured against the tubular body, and the shaft body and the tubular body are in line contact at least in the axial direction, thereby preventing the shaft body from swinging with respect to the tubular body. Can do. Further, the shaft body and the cylindrical body are inserted into the gap fitting including the gap zero. As a result, the shaft body and the cylindrical body can be held at a predetermined position by setting the shaft body and the cylindrical body on the jig without depending on the press-fitting step. For this reason, it is not necessary to introduce a separate press-fitting facility.
[0008]
In addition, a feature of the present invention (a feature of the invention according to claim 2) is that caulking is performed from the outer periphery of the plunger toward the shaft in a state where the base portion of the shaft having the valve portion at the tip is inserted into the insertion hole of the plunger. In the caulking method for integrally connecting the shaft and the plunger in the electromagnetic valve, the insertion of the shaft and the plunger is a gap fitting including a gap zero, and the two-surface width portion formed on the plunger is A pair of punches that are pressed and crimped are provided in an offset state where their respective central axes are not on the same line, and are asymmetric with respect to an axis passing through the axis of the plunger in the two-surface width portion formed on the plunger by to facilities caulking to be at a site other than the caulking portion, the inner periphery of the insertion hole in the plunger and the outer peripheral surface of said shaft There is in that so as to line contact at least the axial direction.
[0009]
According to this, the shaft and the plunger are integrally coupled by line contact in at least the axial direction between the caulking portion of the plunger, the outer peripheral surface of the shaft, and the inner peripheral surface of the insertion hole of the plunger. Thereby, while ensuring the retaining strength with respect to the plunger of the shaft, the shaft and the plunger are in line contact at least in the axial direction, thereby preventing the shaft from swinging with respect to the plunger. Further, the shaft and the plunger are inserted into a gap including zero gap. Thereby, it can hold | maintain in a predetermined position by setting a shaft and a plunger to a jig | tool irrespective of a press injection process, Therefore A caulking process can be performed as it is. For this reason, it is not necessary to introduce a separate press-fitting facility. Further, since temporary fixing by press-fitting is not performed, even if the shaft is thin, it can be inserted without causing bending or buckling.
[0010]
Further, when the invention according to claim 1 or 2 is implemented, when the caulking portion is provided at a plurality of locations (in the case of the invention according to claim 3), sufficient securing strength of the shaft body or the shaft is ensured. It is possible to prevent the shaft body or the shaft from swinging. When the caulking portion is set on a plane substantially orthogonal to the central axis of the shaft body or the shaft (in the case of the invention according to claim 4), a different direction (radial direction) with respect to the central axis In addition, the shaft body or the shaft is not pressed from different heights (axial positions), and the shaft body or the shaft is not tilted by the caulking process. It is fixed parallel to the central axis of the insertion hole. Thereby, the coaxiality of the shaft body or shaft after caulking and the insertion hole can be ensured with high accuracy.
[0011]
In carrying out the invention according to claim 1 or 2, when the caulking portion is provided at one place (in the case of the invention according to claim 5), the shaft body or the shaft extends in one direction of the insertion hole. Since it is pressed and caulked, it is fixed by line contact in at least the axial direction between the caulking portion and the outer peripheral surface of the shaft body or shaft and the inner peripheral surface of the insertion hole. As a result, the shaft body is prevented from coming off from the cylindrical body, and the shaft body and the inner peripheral surface of the insertion hole of the cylindrical body are in contact with each other, so that the shaft body swings relative to the cylindrical body. Can be prevented. Moreover, the deformation | transformation of a plunger outer shape can be suppressed to the minimum by using the crimping process part as one place.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an electromagnetic valve A (liquid valve) including a plunger 10 as a cylindrical body made of a magnetic material and a shaft 20 as a shaft body made of a nonmagnetic material, which are integrally connected by a caulking method according to the present invention. The solenoid valve used in the pressure circuit). In this electromagnetic valve A, the plunger 10 and the shaft 20 are biased by a spring S, and are seated on a valve seat 28 by a spherical valve portion 26 formed at the tip of the shaft 20. The plunger 10 and the shaft 20 are moved against the spring S by energizing the solenoid C so that the valve portion 26 of the shaft 20 is separated from the valve seat 28.
[0017]
As shown in FIG. 2, the plunger 10 is provided with a two-sided width portion 12 on the outer peripheral surface of a cylinder, and an insertion hole 14 is provided to a predetermined depth in the central axis direction of the cylinder. Further, the inner diameter of the insertion hole 14 is set to an inner diameter through which the base portion 22 of the shaft 20 is inserted with a gap (for example, about 10 to 50 μm in the diameter direction) set in advance for the shaft 20. On the other hand, the shaft 20 is a solid cylinder, and two annular grooves 24 are formed in the base portion 22 along the outer periphery.
[0018]
Incidentally, the plunger 10 and the shaft 20 are integrally connected by caulking using the jig 30 shown in FIG. The jig 30 is fixed to a base B installed horizontally, and includes a support portion 32 that accommodates and supports the plunger 10, a through-hole 34 that supports the shaft 20 without tightening, and a plunger 10. A pair of left and right punches 36A and 36B that press and crimp the surface width portion 12 and a lateral hole 38 that slidably accommodates the punches 36A and 36B are provided.
[0019]
The punch 36 </ b> A and the punch 36 </ b> B are formed of an iron-based member having high hardness, and in order to reliably deform the plunger 10 and firmly fix it to the shaft 20, a columnar convex portion 36 a is formed at each tip portion. It is provided on the central axis. Further, the stroke amount pressed by the punches 36A and 36B and the outer diameter and height of the convex portion 36a have an influence on the outer shape of the plunger 10 (the amount of diameter expansion in the orthogonal direction of pressing), and the plunger 10 and the shaft 20 by caulking. And the amount of inclination of the shaft 20 with respect to the axis of the plunger 10 are set.
[0020]
The lateral hole 38 is provided so that the central axes of the punches 36A and 36B are on a plane substantially perpendicular to the central axis of the shaft 20, and when the shaft 20 is set in the through hole 34, the base B It is provided so that the height from the upper surface to the central axis of the concave groove portion 24 and the convex portion 36a is the same. Further, as shown in FIG. 3B, the lateral hole 38 is in a state in which the central axes of the punch 36A and the punch 36B are not collinear, that is, the central axis L1 of the punch 36A passes through the central axis L0 of the plunger 10. The central axis L2 of 36B is provided so as to be offset by a predetermined amount D in the horizontal direction from the central axis L1 of the punch 36A. The predetermined amount (offset amount) D is set mainly based on the outer diameter of the shaft 20, for example, if the outer diameter of the shaft 20 is about 2 mm, it is set to about 0.5 mm. Accordingly, it is possible to optimize the influence on the outer shape of the plunger 10, the coupling force between the plunger 10 and the shaft 20 by caulking, the amount of inclination of the shaft 20 with respect to the axis of the plunger 10, and the like.
[0021]
In the caulking process using the jig 30 having the above-described configuration, first, the shaft 20 is erected with the valve portion 26 positioned downward in the through hole 34 of the jig 30, and the insertion hole 14 and the base portion 22 of the plunger 10 are inserted. Next, the two-surface width portion 12 of the plunger 10 and the punches 36 </ b> A and 36 </ b> B are opposed to each other and set on the support portion 32 of the jig 30. From this state, when the pair of left and right punches 36A and 36B press the two-surface width portion 12 of the plunger 10, the two-surface width portion 12 starts to deform. At this time, since the central axes of the punch 36A and the punch 36B are not on the same line, the shaft 20 is connected to the plunger 10 according to the deformation of the two-surface width portion 12 due to the pressing of the punch 36B that is shifted from the center of the plunger 10. It moves in a direction deviated from the insertion hole 14 (upward in FIG. 3). Subsequently, when the punch 36A and the punch 36B press and deform the two-surface width portion 12, the shaft 20 is fixed at the deformed portion (two caulking portions) of the two-surface width portion 12, and the insertion hole 14 The inner peripheral surface and the outer peripheral surface of the shaft 20 are in line contact at least in the axial direction (the surface may be contacted when caulking is performed with a large force), and the shaft 20 is fixed. Further, since the center of the width of the concave groove portion 24 of the shaft 20 and the central axis of the convex portion 36a of the punch 36A and the punch 36B have the same height from the upper surface of the base B, the deformed portion of the two-surface width portion 12 Engages with the groove 24.
[0022]
For this reason, the plunger 10 and the shaft 20 that are integrally connected through the caulking step are engaged with the deformed portions (two caulking portions) of the plunger 10 and the concave groove portion 24, and after the caulking processing. In this case, a sufficient line contact length is secured. As a result, the shaft 20 does not come out of the plunger 10 with the operation of the solenoid valve A, and swings between the plunger 10 and the shaft 20 (which causes vibration when the solenoid valve A is used). I don't have to.
[0023]
In addition, a predetermined gap is set between the inner peripheral surface of the insertion hole 14 of the plunger 10 and the outer peripheral surface of the shaft 20. For this reason, the insertion hole 14 and the base 22 are inserted without being press-fitted, and the shaft 20 is integrally connected without causing bending or buckling. In addition, there is no need to introduce separate press-fitting equipment, and there is no increase in production equipment costs.
[0024]
Further, the central axes of the punches 36 </ b> A and 36 </ b> B are located on a plane substantially orthogonal to the central axis of the shaft 20. As a result, the shaft 20 does not tilt even after caulking, and the center axis of the shaft 20 is fixed in parallel to the central axis of the insertion hole 14 even after caulking. 14 and the valve portion 26 of the shaft 20 can be secured with high accuracy. Accordingly, the performance of the solenoid valve A (for example, performance such as sealing performance at the seating portion 28 and linear current-flow rate characteristics) can be stably obtained.
[0025]
In the first embodiment, the central axis L1 of the punch 36A passes through the central axis L0 of the plunger 10, and the central axis L2 of the punch 36B is offset from the central axis L1 of the punch 36A by a predetermined amount D in the horizontal direction. However, instead of this, as shown in FIG. 4, the punch 36 </ b> A and the punch 36 </ b> B press the two-sided width portion 12. Also, the direction may be changed. Specifically, as shown in FIG. 4A, the central axes L1 and L2 of the pair of punches 36A and 36B are both shifted in the same direction in the horizontal direction with respect to the central axis L0 of the plunger 10 ( The caulking process may be carried out by changing the portion of the plunger 10 that presses the two-surface width portion 12 by making the caulking process symmetrical with respect to the central axis L0. Further, as shown in FIG. 4B, the central axis L2 of the punch 36B is arranged so as to have a predetermined angle θ (caulking process) with respect to the central axis L1 of the punch 36A passing through the central axis L0 of the plunger. May be asymmetric with respect to the central axis L0), and the caulking may be performed by changing the direction in which the two-surface width portion 12 is pressed. In addition, the black arrow in FIG. 4 (a), (b) shows the site | part and direction to press.
[0026]
In each of the embodiments shown in FIG. 4 as well, the shaft 20 moves in a biased direction with respect to the insertion hole 14 of the plunger 10 in accordance with the deformation of the two-surface width portion 12 by caulking. The shaft 20 is fixed at a line contact portion between the deformed portion of the portion 12 (two caulking portions) and the inner peripheral surface of the insertion hole 14 and the outer peripheral surface of the shaft 20. Thereby, the effect similar to the said 1st Embodiment can be acquired.
[0027]
Further, in the first embodiment, the pair of punches 36A and the punches 36B having the convex portions 36a at the respective tips are used for the caulking process, but as shown in FIG. It is also possible to carry out caulking by using it. In the second embodiment shown in FIG. 5 as well, the configurations of the shaft 20, the plunger 10, and the setting jig 30 are the same as those in the first embodiment.
[0028]
As shown in FIG. 5A, the pair of punches of the second embodiment shown in FIG. 5 includes a punch 46A having a flat surface 46a whose tip matches the two-surface width portion 12 of the plunger 10, and a convex portion. A punch 46B having 46b is provided. By the way, in the flat surface 46a and the convex part 46b, the part which the convex part 46b contacts greatly deform | transforms from the difference in the surface pressure which arises when pressing the two-surface width part 12, and it contacts with the flat surface 46a. The site is hardly deformed. For this reason, due to the deformation of the two-surface width portion 12 by the convex portion 46b, the shaft 20 moves in a direction biased with respect to the insertion hole 14 of the plunger 10 (left direction in FIG. 5B), and further deformation proceeds. And the shaft 20 is fixed at a deformed portion (one caulking portion) of the two-surface width portion 12 and line contact is made at least in the axial direction between the inner peripheral surface of the insertion hole 14 and the outer peripheral surface of the shaft 20. The shaft 20 is fixed, and the deformed portion of the two-surface width portion 12 is engaged with the concave groove portion 24. Thereby, the deformation | transformation by the crimping process of the two-surface width part 12 can be minimized, and the plunger 10 and the shaft 20 can be connected integrally. For this reason, also in the second embodiment, the same effect as that of the first embodiment can be expected.
[0029]
Further, in the second embodiment shown in FIG. 5, the punch 46A having the flat part 46a is adopted, but instead, the flat part 46a of the punch 46A is adopted as the convex part 46b of the punch 46B. If the pressing force of the punch 46A is made smaller than the pressing force of the punch 46B, the shaft 20 can be pushed in and caulked in the direction in which the pressing force is small (in the direction of the punch 46A). The same effect can be expected.
[0030]
In the second embodiment, the pair of punches 46A and 46B are caulked, but instead of this, as shown in FIG. 6, there are four punches, that is, flat portions 46a. It is also possible to carry out caulking with 46A and 46B1, 46B2, and 46B3 (shown by black arrows in FIG. 6) having convex portions 46b. In this case, the same effects as those of the first embodiment can be obtained except that the number of caulking portions becomes three and the number increases so that the retaining strength can be increased.
[0031]
In the first embodiment and the second embodiment, a preset gap (for example, about 10 to 50 μm) is formed between the inner peripheral surface of the insertion hole 14 of the plunger 10 and the outer peripheral surface of the shaft 20. Although implemented as described above, in the present invention, the plunger 10 and the shaft 20 may be configured to be inserted with a clearance fit, and the clearance at that time may be zero.
[0032]
Moreover, in the said 1st and 2nd embodiment, although this invention was implemented in the connection part of the plunger 10 as a cylindrical body, and the shaft 20 as a shaft body, this invention is different from other cylindrical bodies. The present invention is not limited to the above-described embodiment, and can be widely applied to connecting portions with other shaft bodies.
[Brief description of the drawings]
FIG. 1 is a schematic view showing an example of a solenoid valve having a plunger and a shaft connected by the method of the present invention.
FIG. 2 is an enlarged view of a plunger and a shaft shown in FIG.
FIG. 3 is a schematic diagram showing a first embodiment of the present invention.
FIG. 4 is a schematic view showing a modification of the pressing portion and the pressing direction according to the first embodiment of the present invention.
FIG. 5 is a schematic view showing a second embodiment of the present invention.
FIG. 6 is a schematic view showing a modification in the pressing direction according to the second embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Plunger (cylindrical body), 12 ... Two-sided width part, 14 ... Insertion hole, 20 ... Shaft (shaft body), 22 ... Base part, 24 ... Concave groove part, 26 ... Valve part, 30 ... Jig, 32 ... Support part, 34 ... through hole, 36A, 36B, 40 ... punch.

Claims (5)

In the caulking method for connecting the shaft body and the cylindrical body integrally by caulking from the outer periphery of the cylindrical body toward the shaft body in a state where the shaft body is inserted into the insertion hole of the cylindrical body. A pair of punches that press and crimp the two-sided width portions formed in the cylindrical body while inserting the shaft body and the cylindrical body into a gap fit including a gap zero , and each central axis is provided in a state of being not collinear offset by to facilities caulking to be asymmetrical with respect to the axis passing through the axis of the tubular body in two surface width portion formed in the tubular body, the A caulking method, wherein the outer peripheral surface of the shaft body and the inner peripheral surface of the insertion hole in the tubular body are in line contact at least in the axial direction at a portion other than the caulking portion. By caulking from the outer periphery of the plunger toward the shaft with the base of the shaft having the valve portion at the end inserted through the insertion hole of the plunger, the shaft and the plunger in the solenoid valve are integrally connected. In the processing method, the shaft and the plunger are inserted into a gap including zero gap, and a pair of punches that press and caulk the two-surface width portions formed on the plunger are arranged such that their central axes are on the same line. not provided by the offset state, the by to facilities caulking to be asymmetrical with respect to the axis passing through the axis of the plunger to the two surface width portion formed on the plunger, a site other than the crimp The outer peripheral surface of the shaft and the inner peripheral surface of the insertion hole in the plunger should be in line contact at least in the axial direction. Caulking method according to claim.   3. The caulking method according to claim 1, wherein the caulking portion is a plurality of places.   The caulking method according to claim 3, wherein the caulking portion is set on a plane substantially orthogonal to a central axis of the shaft body or the shaft.   The caulking method according to claim 1 or 2, wherein the caulking portion is provided at one place.

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