JP3742495B2 - Servo amplifier housing - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a housing that houses a circuit of a servo amplifier.
[0002]
[Prior art]
In general, a circuit portion including a printed circuit board and a semiconductor element constituting an amplifier is housed in a housing, and thereby, the protection and appearance of internal components are kept good. In such an amplifier, the servo amplifier uses a power semiconductor such as an IGBT, and therefore generates a large amount of heat generated from internal components. Therefore, the servo amplifier includes a heat sink (heat radiator) to dissipate heat outside the amplifier. Yes.
[0003]
For this reason, the housing of the servo amplifier includes a heat sink and a cover as components.
[0004]
10 and 11 are schematic cross-sectional views for explaining a housing of a conventional servo amplifier. In the conventional configuration shown in FIG. 10, the housing of the servo amplifier includes a heat sink 2 and a resin cover 3, and houses a printed circuit board 4 and a power semiconductor element 5 therein. In the servo amplifier housing, the heat sink 2 and the resin cover 3 are formed separately and are connected by screws 6.
[0005]
In addition, in the other conventional configuration shown in FIG. 11, the heat sink 2 and the resin cover 3 constituting the housing of the servo amplifier are formed separately from the heat sink 2 and the resin cover 3 as in FIG. The heat sink 2 and the resin cover 3 are coupled to each other by hooking the snap 7 formed on the end of the resin cover 3 to the end of the heat sink 2. In general, an aluminum heat sink is used.
[0006]
[Problems to be solved by the invention]
The servo amplifier housing used in the past has a structure in which the heat sink and the resin cover are coupled using fixing means such as screw tightening or resin snapping, and thus a fixing means and a tool therefor are required. There is a problem of increasing the number of assembling steps for joining and assembly.
[0007]
Also, since there is a large difference in mechanical strength between the aluminum heat sink and the resin cover, using a fastening method such as screw tightening or resin snap will apply stress to the resin part and reduce the strength of the joint part. In addition, there is a problem of causing a resin crack (A in FIG. 10 and B in FIG. 10).
[0008]
Accordingly, an object of the present invention is to solve the problems of the conventional servo amplifier casing and to provide a servo amplifier casing capable of coupling a heat sink and a resin cover without using fixing means. It is another object of the present invention to provide a housing for a servo amplifier in which the strength of the joint between the heat sink and the resin cover is high.
[0009]
[Means for Solving the Problems]
The housing of the servo amplifier of the present invention combines the heat sink and the resin cover without using a fixing means by integrally molding the heat sink and the resin cover at the same time. The strength of the joint portion between the heat sink and the resin cover is increased by reducing the strength.
[0010]
Therefore, in the servo amplifier housing of the present invention, in order to simultaneously mold the heat sink and the resin cover at the same time, in the servo amplifier housing having the heat sink and the resinous cover, the heat sink has a joint surface to be joined to the cover. The resin cover has a second engagement portion that engages with the first engagement portion, and includes a first engagement portion that is convex, concave, or uneven at least partially. The two engaging portions are formed in contact with the first engaging portion simultaneously with the cover molding.
[0011]
The heat sink is a radiator for radiating heat inside the casing to the outside, and is formed of a material having good thermal conductivity such as aluminum, and constitutes a casing of the servo amplifier together with a resin cover.
[0012]
The resin cover covers the circuit components of the servo amplifier to form a protection and good appearance of the components.
[0013]
According to the housing of the servo amplifier of the present invention, when the resin cover is molded, the resin cover is molded so as to be in contact with the first engagement portion formed on the heat sink joint surface. By this molding, a second engagement portion corresponding to the first engagement portion is formed at the portion where the resin cover comes into contact with the first engagement portion at the same time as the molding. The heat sink and the resin cover are joined by the engagement of the two engaging portions.
[0014]
Therefore, the heat sink and the resin cover are integrally molded at the same time, and this integral molding also joins the heat sink and the resin cover at the same time. Thus, the tool fixing means and therefore is not required, Further, since the stress due to be fixed to the resin portion does not occur, the strength of the joint is Ru Takama.
[0016]
In particular, the housing of the servo amplifier of the present invention, the block configuration of components having at least a first engagement portion of the heat sink, which constitutes a heat sink using a plurality of the blocks, the binding of each block This can be done by engaging the first engagement portion on the heat sink side with the second engagement portion of the resin cover. This allows the use of different blocks of the heat radiation characteristics, by combining different blocks of the radiating characteristics, Ru can configure the housing of the servo amplifier with the heat sink corresponding to the heat radiation characteristics of the servo amplifier.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a cross-sectional view of a servo amplifier housing, FIG. 2 is a partial perspective view of the servo amplifier housing, and FIG. 3 is a cross-sectional view at the time of molding a cover. It explains using.
[0019]
In FIG. 1, a housing 1 includes a heat sink 2 and a resin cover 3 and accommodates a printed circuit board 4 and a power semiconductor element 5 therein. The heat sink 3 can be made of aluminum, and includes a base 21 that is in contact with a heat generating portion such as the power semiconductor element 5 and a heat dissipation fin 22 for releasing heat to the outside. A concave groove 23 is formed in the outer peripheral portion of the base 21 portion of the heat sink 3, thereby constituting a first engaging portion. The groove 23 can be formed over the entire outer periphery of the base 21 or can be formed only in a part of the peripheral portion.
[0020]
The resin cover 3 is molded at least at a position in contact with the groove 23 formed in the base 21 portion of the heat sink 2, and the second engaging portion 12 is formed at a portion engaging with the first engaging portion 11 of the groove 23. Is formed. The heat sink 2 and the resin cover 3 can be joined by the engagement of the first engaging portion 11 and the second engaging portion 12.
[0021]
The perspective view of FIG. 2 shows the base 21 portion of the heat sink 2 and a portion of the resin cover 3. By forming the resin cover 3, a convex second engaging portion 12 corresponding to the groove 23 of the heat sink 2 is formed on the inner surface portion of the resin cover 3 simultaneously with the molding. Therefore, the groove 23 that is the first engaging portion 11 and the second engaging portion 12 are molded in the engaged state.
[0022]
FIG. 3 is a diagram for explaining a process of forming the housing of the servo amplifier. The housing can be formed by mold formation. In forming the casing by this mold formation, at least the first engagement portion 11 of the heat sink 2 is housed inside, and a mold 6 for molding the resin cover 3 is used. Although FIG. 3 shows a configuration example in which the heat sink 2 is stored in the mold 6, the configuration is not necessarily required to store the entire heat sink 2, and the first engagement portion 11 of the heat sink 2 is stored inside. What is necessary is just to have the component which shape | molds the part and the resin-made covers 3. In FIG. 3, the die 6 portion is indicated by hatching.
[0023]
When the heat sink 2 is set in the mold 6, a gap into which resin is inserted is formed between the inner portion of the mold 6 and between the mold 6 and the heat sink 2. This gap becomes a molded part of the resin cover 3. When the molten resin is injected into the gap, the resin fills the gap, and the first engagement portion 11 of the heat sink 2 is deformed corresponding to the shape. After the resin is cured, the mold 6 is removed to complete the molding of the resin cover 3. At this time, the first engagement portion 11 of the heat sink 2 and the second engagement portion 12 of the resin cover 3 are molded in an engaged state, whereby the heat sink 2 and the resin cover 3 are joined at the same time. It is integrally molded.
[0024]
FIG. 4 is a perspective view for explaining a second configuration example of the embodiment of the present invention, and shows the base 21 portion of the heat sink 2 and a part of the resin cover 3 as in FIG. FIG. 4A is a configuration example in which the first engagement portion 24 of the heat sink 2 is formed in a convex shape. In this configuration example, the second engagement portion 12 ′ of the resin cover 3 is formed into a concave shape corresponding to the convex shape 24 on the first engagement portion side.
[0025]
FIG. 4B is a configuration example in which the first engagement portion 24 of the heat sink 2 is formed in a convex shape and a concave shape. In this configuration example, the second engagement portion 12 ′ of the resin cover 3 is formed into a convex shape and a concave shape corresponding to the concave groove 23 and the convex shape 24 on the first engagement portion side. Is done. The depth of the groove 23 can be set arbitrarily.
With the above configuration, as in the first configuration example, the first engaging portion 11 and the second engaging portion 12 are molded in the engaged state.
[0026]
FIG. 5 is a cross-sectional view for explaining a third configuration example of the embodiment of the present invention. The third configuration example is a configuration in which the height of the resin cover is lowered, and the other configuration is the same as the third configuration example. According to this configuration example, the resin cover 3 'covers only the low part of the circuit component, and the high part is in a state in which interference from the outside is possible, so that the maintainability of the circuit component can be improved.
[0027]
6 and 7 are a perspective view and a sectional view of a heat sink for explaining a fourth configuration example of the embodiment of the present invention. In a fourth configuration example, the heat sink 2 is subdivided into a plurality of blocks, and the heat sinks are configured by combining and combining the subdivided blocks. The subdivided block portion may be configured to have at least the first engaging portion 11 ′ in the base portion 21 ′, and the radiating fin 22 ′ may be arbitrarily provided. A block that does not include the heat dissipating fins 22 ′ has only a base portion and can be used as a binding material for other blocks. In addition, in FIG. 6, the case where each block is the same shape and the same dimension is shown, and the case where each is provided with radiation fin 22 'is shown.
[0028]
8 and 9 are a perspective view and a cross-sectional view of a heat sink for explaining a fifth configuration example of the embodiment of the present invention. In the fifth configuration example, as in the fourth configuration example, the heat sink 2 is subdivided into a plurality of blocks, and the subdivided blocks are combined and combined to form a heat sink. The subdivided block portion is configured to have at least first engaging portions 11 ′ and 11 ″ in the base portions 21 ′ and 21 ″, and the radiating fins 22 ′ and 22 ″ are arbitrarily provided. Can do. A block that does not include the heat dissipating fins 22 ′ has only a base portion and can be used as a binding material for other blocks.
[0029]
Each block of the fifth configuration example has a configuration in which the pitch of the base portions 21 ′ and 21 ″ and the height of the radiation fins 22 ′ and 22 ″ are made different. Different heat dissipation characteristics can be obtained by varying the pitch of the blocks and the height of the fins.
[0030]
According to this configuration, blocks having different heat dissipation characteristics can be combined according to circuit components having different heat generation amounts, thereby forming a heat sink.
[0031]
FIG. 9 shows a configuration in which a block corresponding to the heat dissipation characteristic of the power semiconductor element 5 ′ and a block corresponding to the heat dissipation characteristic of the power semiconductor element 5 ″ are combined. This combination can be arbitrarily set according to the heat generation characteristics of the circuit components. When the resin cover is molded, the combination of the blocks is set and arranged, and is integrally molded together with the cover molding.
[0032]
According to the fourth and fifth configurations, the shape and heat dissipation characteristics of the heat sink can be set arbitrarily, and a design with a greater degree of freedom is possible than when one heat sink is formed by extrusion or die casting.
[0033]
The heat sink and the block used for the housing of the servo amplifier of the present invention can be an extruded product, a processed product, an aluminum plate processed product, or an aluminum die cast.
[0034]
【The invention's effect】
As described above, according to the housing of the servo amplifier of the present invention, the heat sink and the resin cover can be coupled without using a fixing means, and the strength of the joint between the heat sink and the resin cover can be increased. Can be increased.
[Brief description of the drawings]
FIG. 1 is a sectional view of a housing of a servo amplifier for explaining a first configuration example of an embodiment of the present invention.
FIG. 2 is a partial perspective view of a housing of a servo amplifier for explaining a first configuration example of an embodiment of the present invention.
FIG. 3 is a cross-sectional view of the servo amplifier casing when molding a cover for explaining a first configuration example of an embodiment of the present invention;
FIG. 4 is a perspective view for explaining a second configuration example of the embodiment of the present invention.
FIG. 5 is a cross-sectional view for explaining a third configuration example of the embodiment of the present invention.
FIG. 6 is a perspective view of a heat sink for explaining a fourth configuration example of the embodiment of the present invention.
FIG. 7 is a cross-sectional view of a heat sink for explaining a fourth configuration example of the embodiment of the present invention.
FIG. 8 is a perspective view of a heat sink for explaining a fifth configuration example of the embodiment of the present invention.
FIG. 9 is a cross-sectional view of a heat sink for explaining a fifth configuration example of the embodiment of the present invention.
FIG. 10 is a schematic cross-sectional view for explaining a housing of a conventional servo amplifier.
FIG. 11 is a schematic cross-sectional view for explaining a housing of a conventional servo amplifier.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Case 2 Heat sink 3,3 'Resin cover 4 Printed circuit board 5 Power semiconductor element 6 Type | mold 11,11', 11 '' 1st engaging part 12 2nd engaging part 21,21 ', 21'' Base part 22, 22 ', 22''Radiation fin 23 Groove 24 Convex part

Claims (1)

In the servo amplifier housing with heat sink and resin cover,
The heat sink is composed of a plurality of blocks provided with a first engaging portion that is convex or concave or concave and convex on at least a part of a joint surface to be joined to the cover,
The resin cover includes a second engagement portion that engages with the first engagement portion, and the second engagement portion is formed in contact with the first engagement portion at the same time as the cover molding . A housing of a servo amplifier that couples a plurality of blocks by engaging an engaging portion and a second engaging portion .

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