Patent Description:
Patent Literature <NUM> (<CIT>) discloses an electrically insulating locating member to be disposed between two substrates, one of the substrates having electrically conductive components mounted thereon such that the components are between the two substrates. The locating member is in contact with the substrate having the components mounted thereon to prevent the components from turning.

As a method for temporarily fixing (positioning and holding) electronic components such as ICs, capacitors, and electrodes at predetermined positions on a substrate, a method using a fixture tool has been generally known. For example, as a method for temporarily fixing a plurality of electronic components at predetermined positions, Patent Literature <NUM> (<CIT>) has been disclosed. According to Patent Literature <NUM>, a fixture tool having a housing portion in which a plurality of electronic components are collectively housed is prepared, and the electronic components are temporarily fixed by pressing the fixture tool against the substrate side while a plurality of electronic components mounted on a predetermined position on a substrate are housed in the housing portion of the fixture tool.

Patent Literature <NUM> (<CIT>) discloses an alternative method for mounting electronic components. First, a spacer is placed on a heat sink having no electronic components mounted thereon. Then, first electronic components are inserted into respective engaging sections in the spacer and are screwed (fastened) to the heat sink. Next, a substrate having second electronic components mounted on a top surface thereof is placed on a top surface of the spacer while inserting terminals of the first electronic components into through-holes of the substrate. Thereafter, the substrate is screwed (fastened) to the heat sink, and the terminals of the first electronic components are soldered to the substrate.

Patent Literature <NUM> (<CIT>) discloses a case member disposed between two substrates, one of which has a connector mounted thereon. The case member comprises: a main frame; connecting bars extending from the main frame; and an auxiliary frame provided at the connecting bars. A resin is filled into the auxiliary frame to firmly fix the connector to the auxiliary frame and the substrate having the connector mounted thereon.

However, for example, in a compact inverter device in which a plurality of electronic components are disposed between two substrates held at a predetermined spacing, it is difficult to temporarily fix the electronic components to be disposed between the substrates by use of a pressing-type fixture tool having a housing portion as in the Patent Literature <NUM>. That is, because a space between the substrates becomes narrow according to downsizing of an inverter, and other electronic components are further disposed around the electronic components disposed between the substrates, it is impossible to secure an area from and to which a pressing type fixture tool having a component housing portion is detached and attached. Therefore, a method for temporarily fixing the electronic components on one of the substrates by soldering in advance, and thereafter, disposing the other substrate so as to sandwich the temporarily-fixed electronic components therebetween may be considered. However, the number of processes for solder-joining the electronic components is increased, which causes another problem of increasing the manufacturing cost of the inverter device.

Therefore, an object of the present invention is to provide a substrate spacing member which is capable of easily positioning and holding components to be disposed between two substrates which are held at a predetermined spacing, and an inverter device.

According to an aspect of the present invention, there is provided a substrate spacing member as specified in claim <NUM>.

According to this substrate spacing member, it is possible to easily position an electrode at the predetermined position even without use of soldering or a tool. Further, it is possible to ground the other substrate via the spacer member by grounding one of the substrates and to easily fix the two substrates on a heat sink by inserting a screw into the through hole of the spacer member.

The branch holding portion may have a first branch holding portion which holds the electrode at the predetermined position, and a second branch holding portion which holds a component adjacent the first branch holding portion.

According to this substrate spacing member, it is possible to temporarily fix components which are disposed adjacent the first branch holding portion by the second branch holding portion provided adjacent to the first branch holding portion.

The term "components" here includes capacitors, resistors, switching elements, substrates, electrodes, wiring busbars, heat radiating sheets, and the like serving as components composing electric equipment such as an inverter.

The frame body portion is formed into a frame form along circumferential edge portions of the substrates, and the substrate spacing member may further have a frame body holding portion which is provided at the frame body portion, and holds the component.

According to this substrate spacing member, because it is possible to temporarily fix components to the circumferential edge portions of the substrates, it is possible to improve the degree of freedom of layout of the components.

The frame body holding portion may have a first frame body holding portion which holds the component, and a second frame body holding portion which holds a component adjacent to the first frame body holding portion.

According to this substrate spacing member, it is possible to temporarily fix components to be disposed adjacent the first frame body holding portion by the second frame body holding portion which is provided adjacent to the first frame body holding portion.

An inverter device according to an aspect of the present invention includes the features specified in claim <NUM>.

According to the present invention, it is possible to easily position and hold (temporarily fix) a component to be disposed between the two substrates which are held at a predetermined spacing.

Hereinafter, an embodiment will be described in detail with reference to the drawings. In addition, the same or corresponding portions in the respective drawings are shown with the same symbols. The dimensional ratios in the drawings are not necessarily proportional to those in the description. In the description, the words referring to directions such as "upper" and "lower" are expedient words based on the states shown in the drawings.

<FIG> is a perspective view showing an inverter device including a substrate spacing member according to an embodiment. In <FIG>, in order to show the layout state of MOS transistors <NUM> and the like which are disposed under a capacitor substrate <NUM>, the capacitor substrate <NUM> is shown in a transparent state. <FIG> is a perspective view showing a state in which the capacitor substrate <NUM> on which capacitors <NUM> are arranged and mounted is removed from the inverter device shown in <FIG>.

An inverter device <NUM> is a so-called three-phase inverter that outputs a three-phase (u/v/w phases) alternating current, and drives a cargo handling motor and a traction motor of a forklift, for example. The inverter device <NUM> mainly includes a heat sink <NUM>, a metal substrate <NUM> on which the MOS (Metal-Oxide-Semiconductor) transistors <NUM> are mounted, a substrate spacing member <NUM>, spacer members <NUM>, electrodes (components) <NUM>, and the capacitor substrate <NUM> on which the capacitors <NUM> are mounted.

The heat sink <NUM> is a member which lowers temperature by a diffusion action of heat generated in power conversion, and the metal substrate <NUM> is placed thereon. The heat transmitted to the heat sink <NUM> from the MOS transistors <NUM> and the like mounted on the metal substrate <NUM> is diffused from fins or the like formed on the surface of the heat sink. For the heat sink <NUM>, metal such as aluminum, copper, or the like with high thermal conductivity is used. Through holes <NUM> and <NUM> (refer to <FIG> and <FIG>) of the metal substrate <NUM> and the capacitor substrate <NUM>, and screw holes <NUM> into which screws <NUM> to be inserted into the spacer members <NUM> are screwed are formed in the vicinity of the circumferential edge portions of the heat sink <NUM>.

As switching elements, for example, the MOS transistors <NUM> are mounted on the metal substrate <NUM>. In the MOS transistors <NUM>, transistor groups 21u, 21v, and 21w are respectively formed for the u phase, the v phase, and the w phase. The MOS transistors <NUM> and the electrodes <NUM> are disposed in consideration of low-inductance, electric current balance, and the like. The through holes <NUM> into which the screws <NUM> which will be described later are inserted are formed in a circumferential edge portion 20a of the metal substrate <NUM>.

The spacer members <NUM> are members for keeping a space between the metal substrate <NUM> and the capacitor substrate <NUM> at a predetermined spacing. The spacer members <NUM> are disposed in the vicinity of the circumferential edge portions 20a and 60a of the metal substrate <NUM> and the capacitor substrate <NUM>. The spacer members <NUM> have through holes 41a into which the screws <NUM> for fastening the metal substrate <NUM> and the capacitor substrate <NUM> to the heat sink <NUM> are inserted.

The substrate spacing member <NUM> is a member for positioning and holding the spacer members <NUM> at predetermined positions at the time of tightening the spacer members <NUM> to be sandwiched between the metal substrate <NUM> and the capacitor substrate <NUM> together. Further, the substrate spacing member <NUM> has a function of positioning and holding the electrodes <NUM> serving as components disposed between the both substrates at predetermined positions. The substrate spacing member <NUM> is formed of an insulating member. As an insulating member, for example, resin, ceramic, or the like is used. The substrate spacing member <NUM> has spacer member holding portions <NUM>, a frame body portion <NUM>, branch portions <NUM>, and electrode holding portions (branch holding portions) <NUM>.

The spacer member holding portions <NUM> are portions for holding the spacer members <NUM>. A plurality of the spacer member holding portions <NUM> are formed. In the substrate spacing member <NUM> of the present embodiment, the spacer member holding portions <NUM> are formed by two pairs of three, that is, six in total, along the long side direction. The spacer member holding portions <NUM> are formed according to the number and the layout positions of the spacer members <NUM> which are appropriately determined in consideration of the sizes and the like of the metal substrate <NUM> and the capacitor substrate <NUM>.

The frame body portion <NUM> is a portion which connects the plurality of spacer member holding portions <NUM> together, and is formed into a frame form along the circumferential edge portions 20a and 60a of the metal substrate <NUM> and the capacitor substrate <NUM>.

The branch portions <NUM> are portions which extend from the frame body portion <NUM> or the spacer member holding portions <NUM> up to the above-described predetermined positions when the spacer members <NUM> are held by the spacer member holding portions <NUM>. In the substrate spacing member <NUM> of the present embodiment, the two branch portions <NUM> are formed. One of the branch portions <NUM> is formed so as to extend from the spacer member holding portion <NUM> up to an attaching position of the electrode <NUM> between the metal substrate <NUM> and the capacitor substrate <NUM>. The other branch portions <NUM> are formed so as to extend from the frame body portion <NUM> up to an attaching position of the electrode <NUM> between the metal substrate <NUM> and the capacitor substrate <NUM>.

The electrode holding portions <NUM> are portions which are provided at the tip ends of the branch portions <NUM>, and hold the electrodes <NUM> at the attaching positions of the electrodes <NUM> between the metal substrate <NUM> and the capacitor substrate <NUM>. In the substrate spacing member <NUM> of the present embodiment, the two electrode holding portions <NUM> are provided. The electrodes <NUM> are inserted into the electrode holding portions <NUM>.

The electrodes <NUM> form electric pathways between the metal substrate <NUM> and the capacitor substrate <NUM>. The electrodes <NUM> are formed of current-carrying materials. Examples of the current-carrying materials include aluminum, brass, and the like. Further, plate processing may be applied to the electrodes <NUM>. Positions (attaching positions) at which the electrodes <NUM> are disposed between the metal substrate <NUM> and the capacitor substrate <NUM> are determined in consideration of inductance, electric current balance, and the like of the inverter device <NUM>. According to downsizing of the inverter device <NUM>, the electrodes <NUM> are disposed in the central portions of the transistor groups composed of the plurality of MOS transistors <NUM> which are connected sequentially.

The capacitors <NUM> are mounted on the capacitor substrate <NUM>. The through holes <NUM> into which the spacer members <NUM> are inserted are formed in the vicinity of the circumferential edge portion 60a of the capacitor substrate <NUM>.

The metal substrate <NUM> and the capacitor substrate <NUM> are fastened to the heat sink <NUM> with the screws <NUM> so as to be at a predetermined spacing with the spacer members <NUM>. The screws <NUM> are inserted into the through holes <NUM>, the spacer members <NUM>, and the through holes <NUM>. The screws <NUM> are inserted from the side of the capacitor substrate <NUM>, to be screwed into the screw holes <NUM> of the heat sink <NUM>.

Next, an assembling method of the inverter device <NUM> will be described by use of <FIG>, and <FIG>. <FIG>, and <FIG> are diagrams showing an embodiment of an assembling method of the inverter device <NUM>.

First, as shown in <FIG>, the metal substrate <NUM> is placed on the heat sink <NUM>. At this time, alignment is performed such that the positions of the screw holes <NUM> of the heat sink <NUM> and the positions of the through holes <NUM> of the metal substrate <NUM> are matched to one another.

Next, the electrodes <NUM> are inserted into the electrode holding portions <NUM>, and further, the substrate spacing member <NUM> in which the spacer members <NUM> are held by the spacer member holding portions <NUM> is prepared. Then, the substrate spacing member <NUM> holding the spacer members <NUM> and the electrodes <NUM> is placed on the metal substrate <NUM> (refer to <FIG>). At this time, alignment is performed such that the positions of the through holes 41a of the spacer members <NUM> and the positions of the through holes <NUM> of the metal substrate are matched to one another.

This substrate spacing member <NUM> is formed such that the electrode holding portions <NUM> are disposed on the above-described predetermined positions when the substrate spacing member <NUM> is placed on the metal substrate <NUM> such that the spacer member holding portions <NUM> are matched to the layout positions of the spacer members <NUM> on the metal substrate <NUM>, i.e., the layout positions of the through holes <NUM> of the metal substrate <NUM>. Therefore, provided that the substrate spacing member <NUM> in a state in which the electrodes <NUM> are held by the electrode holding portions <NUM> is prepared, and is mounted such that the positions of the spacer member holding portions <NUM> of the substrate spacing member <NUM> are matched to the through holes <NUM> on the metal substrate <NUM>, the electrodes <NUM> are positioned and held at desired positions intended to be fixed between the metal substrate <NUM> and the capacitor substrate <NUM>.

Next, as shown in <FIG>, the capacitor substrate <NUM> is mounted on the metal substrate <NUM> in which the electrodes <NUM> are positioned and held by the substrate spacing member <NUM>. At this time, alignment is performed such that the positions of the through holes <NUM> of the capacitor substrate <NUM> and the positions of the through holes 41a of the spacer members <NUM> are matched to one another.

Next, the screws <NUM> are inserted into the through holes <NUM> of the capacitor substrate <NUM>, the through holes 41a of the spacer members <NUM>, and the through holes <NUM> of the metal substrate <NUM>, to be screwed into the screw holes <NUM> provided in the heat sink <NUM>. Accordingly, the electrodes <NUM> and the spacer members <NUM> are tightened together by the metal substrate <NUM> and the capacitor substrate <NUM>. Then, components such as an input terminal which are not shown in the drawings are attached, which completes the inverter device <NUM> as shown in <FIG>.

The substrate spacing member <NUM> of the above-described embodiment is formed such that the electrode holding portions <NUM> are capable of holding the electrodes <NUM> which are rectangular in planar view.

Although one embodiment has been described above, the present invention is not limited to the above-described embodiment, and various modifications are possible within the scope defined by the claims.

The substrate spacing member <NUM> of the above-described embodiment has been described by use of the example of the branch portions <NUM> of a shape extending from the spacer member holding portions <NUM> or the frame body portion <NUM> up to the attaching position of the electrodes <NUM> as shown in <FIG>. However, the present invention is not limited this example.

For example, as shown in <FIG>, the branch holding portion <NUM> may have a first branch holding portion 37a which holds the component <NUM> at the predetermined position, and a second branch holding portion 37b which holds a component <NUM> around the first branch holding portion 37a.

Further, for example, as shown in <FIG>, the branch holding portion <NUM> may have a second branch holding portion 37c which extends toward the adjacent branch holding portion <NUM>, and holds a component <NUM> around the first branch holding portion 37a. Here, the adjacent branch holding portion <NUM> has the second branch holding portion 37c with the same configuration, thereby, it is possible to hold the component <NUM> around the first branch holding portion 37a. In addition, <FIG> shows the example in which the second branch holding portions 37c adjacent to one another are integrally formed. However, it may be a configuration in which those are spaced from each other.

The second branch holding portions 37b and 37c extending from the first branch holding portion 37a may be integrated with the first branch holding portion 37a, or may be separated from the first branch holding portion 37a.

According to this configuration of the substrate spacing member <NUM>, it is possible to position and hold the components <NUM> and <NUM> disposed around the first branch holding portion 37a. Therefore, there is no need to provide a new branch portion and branch holding portion for holding there components <NUM> and <NUM>.

Further, for example, as shown in <FIG>, the frame body portion <NUM> may be formed into a frame form along the circumferential edge portions of the metal substrate (substrate) <NUM> and the capacitor substrate (substrate) <NUM>, and the substrate spacing member <NUM> may further include a frame body holding portion <NUM> which is provided at the frame body portion <NUM>, and holds a component <NUM> (<NUM>, <NUM>). According to this configuration of the substrate spacing member <NUM>, it is possible to position and hold the components <NUM> (<NUM>, <NUM>) at the circumferential edge portions of the metal substrate <NUM> and the capacitor substrate <NUM> as well. Therefore, it is possible to improve the degree of freedom of layout of the components.

Further, for example, as shown in <FIG>, the frame body holding portion <NUM> may have a first frame body holding portion 131a which holds the component <NUM> at a predetermined position, and a second frame body holding portion 131b which holds a component <NUM> around the first frame body holding portion 131a.

Further, for example, as shown in <FIG>, the frame body holding portion <NUM> which holds the component <NUM> may have a second frame body holding portion 131c which extends toward the adjacent frame body holding portion <NUM>, and holds a component <NUM> around the first frame body holding portion 131a. Here, the adjacent frame body holding portion <NUM> has the second frame body holding portion 131c with the same configuration, thereby, it is possible to hold the component <NUM> around the first frame body holding portion 131a. In addition, <FIG> shows the example in which the second frame body holding portions 131c adjacent to one another are integrally formed. However, it may be a configuration in which those are spaced from each other.

The second frame body holding portions 131b and 131c extending from the first frame body holding portion 131a may be integrated with the first frame body holding portion 131a, or may be separated from the first frame body holding portion 131a.

According to this configuration of the substrate spacing member <NUM>, it is possible to position and hold the components <NUM> and <NUM> disposed around the first frame body holding portion 131a. Therefore, there is no need to provide a new frame body holding portion <NUM> for holding there components <NUM> and <NUM>.

Moreover, for example, as shown in <FIG>, the branch holding portion <NUM> may have the second branch holding portion 37c which extends toward the adjacent frame body holding portion <NUM>, and holds a component <NUM> around the first branch holding portion 37a. Here, the adjacent frame body holding portion <NUM> has the second frame body holding portion 131c with the same configuration, thereby, it is possible to hold the component <NUM> around the first branch holding portion 37a. In addition, <FIG> shows the example in which the second branch holding portion 37c and the second frame body holding portion 131c adjacent to one another are integrally formed. However, it may be a configuration in which those are spaced from each other.

The second branch holding portion 37c extending from the first branch holding portion 37a may be integrated with the first branch holding portion 37a, or may be separated from the first branch holding portion 37a. The second frame body holding portion 131c extending from the first frame body holding portion 131a may be integrated with, or may be separated from the first frame body holding portion 131a.

According to this configuration of the substrate spacing member <NUM>, it is possible to position and hold the component <NUM> disposed around the first branch holding portion 37a. Therefore, there is no need to provide the new branch holding portion <NUM> for holding this component <NUM>.

Further, for example, as shown in <FIG> and <FIG>, the branch portions <NUM> may be provided so as to connect the spacer member holding portions <NUM> or the frame body portion <NUM> provided on one of the long sides and the spacer member holding portions <NUM> or the frame body portion <NUM> provided at the opposite position. In other words, the branch portions <NUM> may be formed in a grid pattern. Accordingly, it is possible to improve the accuracy of position at the time of positioning and holding the components <NUM> at predetermined positions on the metal substrate <NUM>.

Moreover, as shown in <FIG>, the substrate spacing member <NUM> may include a connection portion <NUM> for directly connecting the frame body portion <NUM> and the frame body portion <NUM>. Accordingly, it is possible to maintain the shape of the substrate spacing member <NUM>, and it is possible to position and hold a target component at a more precise position.

Further, with the configuration in which it is possible to fix the spacer members <NUM> to the heat sink <NUM>, it is possible to fix the spacer members <NUM> in a state in which the metal substrate <NUM> is mounted on the heat sink <NUM>, and dispose the substrate spacing member <NUM> so as to hold the spacer members <NUM>. In this way, it is possible to improve the accuracy of position at the time of positioning and holding the electrodes <NUM> between the metal substrate <NUM> and the capacitor substrate <NUM>. In addition, as a configuration in which the spacer members <NUM> are fixed to the heat sink <NUM>, a configuration in which a screw groove may be provided in the edge portion of the spacer member <NUM>, so as to be able to screwed into the screw hole <NUM> provided in the heat sink <NUM> may be adopted, or a fit-in portion to be fit into the screw hole <NUM> may be provided at the edge portion of the spacer member <NUM>.

Further, claw portions for positioning the substrate spacing member <NUM> at a predetermined position on the metal substrate <NUM> may be provided at the spacer member holding portions <NUM> and the frame body portion <NUM>, or the like. Even in such a case, it is possible to improve the accuracy of position at the time of positioning and holding the electrodes <NUM> on the metal substrate <NUM>.

In the above-described embodiment, the example in which the spacer member <NUM> and the electrode <NUM> are respectively inserted into (pressed into) the spacer member holding portion <NUM> and the electrode holding portion <NUM> has been described. However, the spacer member <NUM> and the spacer member holding portion <NUM> may be integrally formed, or the electrode <NUM> and the electrode holding portion <NUM> may be integrally formed.

The substrate spacing member <NUM> of the above-described embodiment has been described by use of the example in which the electrode holding portions <NUM> are formed so as to be capable of holding the electrodes <NUM> which are rectangular in planar view. However, it is not limited to this example. The holding portions <NUM> may be formed so as to be capable of holding the electrodes <NUM> which are circular, oval, or polygonal in planar view.

Claim 1:
A substrate spacing member (<NUM>) which is configured to be disposed between two substrates (<NUM>, <NUM>) on which electronic components (<NUM>, <NUM>) are mounted at least on one of the two substrates (<NUM>) such that the electronic components (<NUM>) thereon are configured to be between the two substrates (<NUM>, <NUM>), and to keep a distance between the two substrates (<NUM>, <NUM>) constant, the substrate spacing member (<NUM>) comprising:
spacer portions (<NUM>, <NUM>) which are configured to be disposed between the two substrates (<NUM>, <NUM>) in contact with both edge portions (20a, 60a) thereof, to keep a distance between the two substrates (<NUM>, <NUM>) constant;
a frame body portion (<NUM>) that connects the spacer portions (<NUM>, <NUM>) together;
a branch portion (<NUM>) which extends toward a predetermined position between the electronic components (<NUM>) between the two substrates (<NUM>, <NUM>), from the frame body portion (<NUM>) or the spacer portion (<NUM>, <NUM>); and
a branch holding portion (<NUM>) which is provided at the branch portion (<NUM>) and holds an electrode (<NUM>), the electrode (<NUM>) configured to electrically connect the two substrates (<NUM>, <NUM>) and to be positioned and held by the branch holding portion (<NUM>) at the predetermined position, wherein
each of the spacer portions (<NUM>, <NUM>) includes a spacer member (<NUM>) which has conductive properties and includes a through hole (41a) into which a screw (<NUM>) is able to be inserted, and a spacer member holding portion (<NUM>) which is formed of an insulating body and holds the spacer member (<NUM>).