JP2005327765A - Support structure of electromagnetic coil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the support structure of an electromagnetic coil that stably supports a coil 2 by providing a spacer 31 made of rubber-like elastic substance in a clearance 3 between the inner face 1a for housing an electrogamgentic coil such as a solenoid valve or the like and the coil 2, and delays changing of the reaction force production manner of the spacer to a compressed reaction force from a lip bending reaction force so as to minimize the maximum reaction force produced as a result. <P>SOLUTION: The spacer 31 is provided with bending deformable lips 32 and 34 around the inner and outer circumferences thereof respectively, and it is formed flat and elastically deformable as a whole. When an axial-direction clearance 3 is comparatively large, the spacer 31 presses and supports the electromagnetic coil 2 by a reaction force accompanied with the bending deformation of the lips 32 and 34, while the axial-direction clearance 3 is comparatively small, the spacer 31 is flatly and elastically deformed as a whole, and presses and supports the electromagnetic coil 2 by a reaction force accompanied with the compression deformation. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electromagnetic coil support structure for stably supporting an electromagnetic coil in an electromagnetic device such as an electromagnetic valve.

  For example, in an electromagnetic valve assembled in a vehicle hydraulic unit mounted on an ABS (anti-lock brake system), since a plurality of parts are assembled, the axial width of the electromagnetic coil housing space varies. An axial gap is generated between the inner surface of the electromagnetic coil housing space and the electromagnetic coil. Further, the size of the gap in the axial direction also varies in the actual range of about 0.4 to 1.2 mm (difference of 0.8 mm). The axial direction is the central axial direction of the electromagnetic coil.

  For this reason, conventionally, a spacer made of a rubber-like elastic body is interposed in the axial gap to absorb the variation and stably support the electromagnetic coil. However, the spacer is within the variation range. It is required to set the maximum reaction force at the time of compression as small as possible so as not to damage the coil housing and the electromagnetic coil while maintaining the minimum reaction force for supporting the electromagnetic coil in any of the dimensions. In particular, recently, since the tendency of the strength to decrease with the resinization of the coil housing is seen, there is an increasing demand for reducing the maximum reaction force during compression.

As shown in FIG. 4, it is conceivable to first use a squeeze-shaped rubber ring (O-ring) 11 having an O-shaped cross section as a spacer. That is, the electromagnetic coil 2 is accommodated in the electromagnetic coil accommodating space 1 of the electromagnetic valve, and an O-ring 11 is interposed in the axial gap 3 generated between the inner surface 1a of the accommodating space 1 and the electromagnetic coil 2 at this time. By pressing the electromagnetic coil 2 against the inner surface 1b on the opposite side of the accommodation space 1 by the reaction force (compression reaction force) accompanying the compression deformation of the ring 11, rattling generated in the electromagnetic coil 2 is prevented. In this case, the minimum reaction force is ensured by setting the axial width w ₁ in the free state of the O-ring 11 to be larger than the maximum value D _max of the axial gap 3 between the inner surface 1 a and the electromagnetic coil 2.

However, in case of using the squeeze-like O-ring 11 as the spacer, since the when the dimension D ₁ of the axial gap 3 is small as shown in FIG. 5, the O-ring 11 is made to large compressive deformation, The compression amount becomes extremely large, and as a result, the reaction force becomes excessive and the coil housing 4 and the electromagnetic coil 2 are damaged, or the compression amount is excessive and the O-ring 11 is compressed and cracked. There is.

  As shown in FIGS. 6A and 6B, it is conceivable to use a rubber ring (X ring) 21 having an X-shaped cross section as a spacer. As the name suggests, the X ring 21 is provided with lips 22 and 23 on one inner and outer periphery in the axial direction and on the other inner and outer periphery in the axial direction, respectively. The electromagnetic coil 2 is pressed against the inner surface (not shown) on the opposite side of the accommodation space 1 by a bending reaction force, thereby preventing backlash generated in the electromagnetic coil 2.

  However, when the X-ring 21 having the four lips 22 and 23 is used as a spacer in this way, the lips 22 and 23 in both the axial directions exceed the state of FIG. When further compression is performed from the completely closed state, the reaction force generation mode is switched from the bending reaction force to the compression reaction force, and at this time, the magnitude of the reaction force rapidly increases. Therefore, even this X-ring 21 cannot sufficiently satisfy the requirement for reducing the maximum reaction force during compression, and thus there is a possibility that the same problem as in the case of the O-ring 11 may occur. Further, in the X ring 21, it is conceivable to reduce the wall thickness of the lips 22 and 23 so as to delay the switching to the compression reaction force. However, because the parts themselves are originally extremely small for convenience of use for electromagnetic valves, There is a limit to reducing the wall thickness in terms of molding. In addition, when trying to cope by lowering the rubber hardness to about Hs40 or less, since the minimum necessary reaction force is insufficient, the rubber thickness must be increased, and as a result, the time to switch to the compression reaction force becomes earlier, Therefore, the reaction force becomes excessive (works more and more disadvantageously on both the upper limit side and the lower limit side of the required reaction force).

  As another conventional technique for this application, as disclosed in Japanese Patent Laid-Open No. 8-54080, a bush made of silicone rubber is interposed between the housing and the electromagnetic coil, or Japanese Patent Laid-Open No. 11-43031. However, none of these bushes or elastic bodies have a lip, and thus the squeeze-like shape is not shown. It is only equivalent to an O-ring.

JP-A-8-54080 JP 11-43031 A

  In view of the above, the present invention makes it possible to make the generation of the reaction force in the spacer slower than before by switching from the lip bending deformation (bending reaction force) to the compression deformation (compression reaction force). Therefore, an object of the present invention is to provide an electromagnetic coil support structure in which the magnitude of the maximum reaction force determined by the compression amount after switching can be set smaller than that of the conventional one.

  In order to achieve the above object, the electromagnetic coil support structure of the present invention accommodates an electromagnetic coil in an electromagnetic coil accommodating space in an apparatus having an electromagnetic coil such as an electromagnetic valve, and an inner surface of the accommodating space and a shaft between the electromagnetic coils. In the electromagnetic coil support structure that stably supports the electromagnetic coil by interposing a spacer made of a rubber-like elastic body in the direction gap, the spacer has one lip that can be bent and deformed on the inner and outer circumferences as a whole. The electromagnetic coil is pressed and supported by a reaction force accompanying bending deformation of the lip when the axial gap is relatively large, and when the axial gap is relatively small The spacer is elastically deformed into a flat shape as a whole, and the electromagnetic coil is pressed and supported by a reaction force accompanying the compression deformation. It is intended to.

In the X-ring 21 of FIG. 6 according to the above prior art, the reaction force generation mode was switched relatively quickly from the bending reaction force to the compression reaction force as shown in FIG. 6B. a because had switched to compression reaction force when the lip 22 and 23 together to close, i.e. the dimension D ₂ of the axial gap 3 is switched to the compression reaction force when smaller than the thickness of the lip 22, 23 two minutes Because it was. On the other hand, in the support structure of the present invention having the above-described configuration, the spacer has one lip that can be bent and deformed on the inner and outer circumferences, and has a shape that can be elastically deformed in a flat shape as a whole. In addition, the reaction force generation mode is switched to the compression reaction force only when the size of the gap in the axial direction approaches the thickness of one lip or approaches it. Therefore, since the situation that the X ring is already switched but cannot be switched according to the present invention, the switching to the compression reaction force can be made slower than that in the prior art. The magnitude of the maximum reaction force determined by the amount of compression can be set smaller than in the past. This is because if the switching to the compression reaction force is delayed, the amount of subsequent compression can be reduced.

  The present invention has the following effects.

  That is, in the support structure of the present invention, due to the above configuration and operation, the reaction force is generated from the bending reaction force to the compression reaction force only when the size of the axial gap approaches the thickness of one lip or approaches it. Since the switching to the compression reaction force is slower than in the prior art, the magnitude of the maximum reaction force determined by the compression amount after the switching can be set smaller than in the past. Therefore, it is possible to effectively prevent the occurrence of damage due to excessive reaction force.

  As described above, according to the present invention, the spacer interposed in the axial gap has one lip that can be bent and deformed on the inner and outer peripheries and can be elastically deformed into a flat shape as a whole. Specifically, for example, it is preferable to have a U-shaped section, a V-shaped shape, a recessed shape, or the like.

Further, the present invention includes the following contents.
Configuration) Regarding the cross-sectional shape of the spacer, the conventional two-part configuration with the lip facing up and down is only one part on one side (U type, reverse U type, V type, reverse V type, concave type, All reverse concave types are included). In particular, the cross-sectional shape is preferably a U-shaped lip-shaped rubber ring.
(Effect) According to the above configuration, the switching to the compression reaction force can be delayed, so that the minimum reaction force can be ensured and the maximum reaction force can be reduced even when the gap variation range is large.

  Next, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows an embodiment of the present invention, that is, FIG. 1A is a half-sectional view in a free state of a spacer (also referred to as a buffer rubber or a rubber ring) 31 used in a support structure according to an embodiment of the present invention. FIG. 1B shows an explanatory diagram of a state in which the spacer 31 is mounted and the electromagnetic coil 2 is supported.

That is, the support structure according to the embodiment accommodates the electromagnetic coil 2 in the electromagnetic coil housing space 1 of the electromagnetic valve, and the axial gap 3 generated between the inner surface 1a of the housing space 1 and the electromagnetic coil 2 at this time. An annular spacer 31 made of a rubber-like elastic body is interposed, and the electromagnetic coil 2 is pressed against the inner surface (not shown) on the opposite side of the accommodation space 1 by the elasticity of the spacer 31, thereby causing a backlash generated in the electromagnetic coil 2. The spacer 31 has one lip 32, 34 that can be bent and deformed on the inner and outer circumferences, and can be elastically deformed in a flat shape as a whole when an axial load is applied. There, with those formed in the dimension in the thickness E ₂ following the lip 32 over its thickness E ₁ in the radial direction the entire length, the size D ₃ of the axial gap 3 is lip 32, The electromagnetic coil 2 as well as pressed and supported by the reaction force due to the bending deformation of the lip 32, 34 when it is 4 in the thickness E ₂ or more (bending reaction force to the bending elasticity), the size of the axial gap 3 lip 32 When the thickness is smaller than the thickness E _{2, the} electromagnetic coil 2 is configured to be pressed and supported by a reaction force (compression reaction force or compression elasticity) accompanying compression deformation of the spacer 31.

In this embodiment, as shown in FIG. 1A, the spacer 31 is formed into a ring shape using a predetermined rubber-like elastic body as a molding material, and has an outer peripheral lip 32, an inversion portion (also referred to as a base portion) 33, and an inner peripheral portion. The lip 34 is integrally formed to have a substantially U-shaped or substantially V-shaped cross section. As a molding material for the spacer 31, silicone rubber or the like is suitable because the temperature range is wide as the use environment of the solenoid valve and oil water is not used. Furthermore, the thickness E ₁ of the spacer 31 are all uniform up to the distal end portion of the inner peripheral lip 34 around the reversing portion 33 from the tip of the radial entire length i.e. the outer peripheral lip 32 and thus all the lip 32 of has been the same as the thickness dimension _{E 2,} if the function or effect of the spacer 31, the thickness of the portion other than the lip 32, 34 (bending portion 33) than the thickness _{E 2} of the lip 32 It may be formed small. On the contrary, the need to ensure a minimum reaction force, there is a case where the thickness dimension of the portion other than the lip 32, 34 is slightly larger than the thickness E ₂ of the lips 32, 34. The axial width w ₂ in the free state of the entire spacer 31 and the axial height h ₁ in the free state of the lips 32 and 34 are both from the thickness dimension E _{2 of the} lips 32 and 34 or the thickness dimension E _{1 of the} spacer 31. Is also set large, and in the figure it is set quite large. The outer peripheral lip 32 and the inner peripheral lip 34 are mutually the same thickness E ₂ and the axial height h _1.

  Therefore, when an axial load acts on the spacer 31 in the free state of FIG. 1A, the spacer 31 is gradually crushed, the outer peripheral lip 32 gradually faces radially outward, and the inner peripheral lip 34 Gradually inward in the radial direction, the angle formed by the lips 32 and 34 gradually increases, and finally becomes a flat shape, that is, a single flat plate shape. After that, the situation where the compression reaction force is generated is the situation where this occurs.

In the support structure having the above structure, as described above, the spacer 31 has one lip 32, 34 that can be bent and deformed on the inner and outer circumferences, and elastically deforms in a flat shape as a whole when an axial load is applied. in order to use one over the thickness E ₁ in the radial direction the entire length is formed to a thickness E ₂ following dimensions of the lip 32, the size of the axial gap 3 of the lip 32, 34 one minute only if smaller than the thickness E ₂ generation mode of the reaction force is switched to the compression reaction force. Therefore, since the situation that the X-ring is already switched but cannot be switched according to the present invention, the switching to the compression reaction force can be made slower than the conventional one, and therefore, after the switching, The magnitude of the maximum reaction force determined by the amount of compression can be set smaller than in the past. Therefore, it is possible to effectively prevent the generated reaction force from becoming excessive and causing damage to the coil housing 4 and the electromagnetic coil 2.

  In addition, since the reaction force of the spacer 21 which concerns on the conventional example (FIG. 6) which consists of silicone rubber of hardness Hs50, and the spacer 31 which concerns on an Example (FIG. 1) was measured, the result is shown on the graph of FIG. The reaction force in the variation range of 0.4 to 1.2 mm of the gap 3 is considered to be within 5.5 to 140 N. In the conventional example, the reaction force in the vicinity of 0.4 mm is excessive and has reached the upper limit of 140 N, but the embodiment is within the range (the lower limit is barely a problem).

  Moreover, about the spacer 31 which concerns on an Example (FIG. 1), the result of having measured the reaction force by changing the hardness of silicone rubber into Hs50, 60, 70, 80 is shown in the graph of FIG. As a result, it was confirmed that the reaction force in the gap of 0.4 to 1.2 mm was all within the required 5.5 to 140 N, and it was confirmed that there was no problem, but there was a margin in the magnitude of the minimum reaction force. To Hs 70-80 is just right.

(A) is a half sectional view in a free state of a spacer used in a support structure according to an embodiment of the present invention, (B) is an explanatory diagram of a state in which the spacer is mounted and an electromagnetic coil is supported The graph which shows the relationship between the clearance gap and reaction force in the spacer which concerns on a prior art example and an Example The graph which shows the relationship between the clearance gap in the spacer which concerns on an Example, and reaction force Explanatory drawing of a state (when the gap is large) in which the spacer according to the conventional example is attached and the electromagnetic coil is supported Explanatory drawing of a state where the spacer is attached and the electromagnetic coil is supported (when the gap is small) (A) is a half-sectional view in a free state of a spacer used in a support structure according to another conventional example, and (B) is an explanatory diagram of a state in which the spacer is mounted and an electromagnetic coil is supported (when the gap is large). Explanatory drawing of a state where the spacer is attached and the electromagnetic coil is supported (when the gap is small)

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electromagnetic coil accommodation space 1a Inner surface 2 Electromagnetic coil 3 Axial direction gap 4 Coil housing 31 Spacer 32, 34 Lip 33 Reverse part

Claims (1)

An electromagnetic coil (2) is housed in an electromagnetic coil housing space (1) in a device having an electromagnetic coil (2) such as a solenoid valve, and the space between the inner surface (1a) of the housing space (1) and the electromagnetic coil (2). In the electromagnetic coil support structure that stably supports the electromagnetic coil (2) by interposing a spacer (31) made of a rubber-like elastic body in the axial gap (3),
The spacer (31) has one lip (32) (34) that can be bent and deformed on the inner and outer peripheries, and has a shape that can be elastically deformed in a flat shape as a whole, and the axial gap (3) Is relatively large, the electromagnetic coil (2) is pressed and supported by the reaction force accompanying the bending deformation of the lips (32), (34), and when the axial gap (3) is relatively small, the spacer (31) An electromagnetic coil support structure, wherein the electromagnetic coil (2) is elastically deformed in a flat shape as a whole and pressed and supported by a reaction force accompanying the compression deformation.

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