JP2011203315A - Electrical connection structure and image forming apparatus including the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrical connection structure which is suitable for achieving low profile of a power supply part and also achieves superior electrical connection, and to provide an image forming apparatus including the same.SOLUTION: A unit side contact 21 provided in a unit 2 and a body side contact 31 provided on an electrical substrate 30 of an apparatus body are electrically connected by an elastic conductive member 40. The electrical substrate 30 includes a through-hole 32, and the body side contact 31 is provided on one surface of the electrical substrate 30 while it extends over an opening of the through-hole 32. The elastic conductive member 40 has a first contact that comes into contact with the body side contact 31 and a second contact that comes into contact with the unit side contact 21, and is inserted through the through-hole 32 from the other surface 30b side of the electrical substrate 30. A support regulation part 50 guides the first contact of the elastic conductive member 40 to the body side contact 31 and also supports the end of the elastic conductive member on the first contact side to regulate the first contact to a position where the first contact is opposed to the body side contact 31.

Description

  The present invention relates to an electrical connection structure and an image forming apparatus including the same.

  Image forming apparatuses such as printers, copiers, and multifunction machines that form images by an electrophotographic system include various units such as a photosensitive drum, a charger, an exposure device, a developing device, a transfer roller, and a fixing device. These units are detachably provided on the apparatus main body from the viewpoint of facilitating replacement and maintenance. Then, when various units are mounted on the device body, an electrical path for supplying power from the device body to the unit and an electrical path for notifying the device body of the output signal of the detector provided on the unit side are established. Is done.

  For establishing such an electrical path, a connection structure is used in which a contact provided on the apparatus main body side and a contact provided on the unit side are electrically connected using a conductive member. For example, Patent Document 1 discloses that when a unit is mounted on the apparatus main body using a conductive member formed of a two-stage conductive compression coil spring in which a large diameter portion and a small diameter portion are connected, A technique for electrically connecting a contact portion of a unit is disclosed. In this technique, a circular hole having a diameter larger than the small diameter portion of the coil spring and smaller than the large diameter portion is formed in the frame portion of the apparatus main body, and the small diameter portion of the coil spring is inserted into the circular hole, so that the unit mounting portion The large-diameter portion is elastically mounted between the frame portion and the power supply substrate in a compressed state.

JP 2007-304447 A

  In the configuration disclosed in Patent Document 1, the base end portion of the conductive compression coil spring elastically mounted between the frame portion and the power supply substrate is elastically contacted with the contact portion provided on the power supply substrate and stably held. Therefore, in this configuration, it is necessary to form a contact portion on the coil spring contact surface of the power supply board. Further, in Patent Document 1, the contact portion is formed as a part of the printed wiring. However, the contact portion is a portion on which the urging force (repulsive force) of the coil spring compressed by the unit mounting acts. Therefore, from the viewpoint of preventing an increase in contact resistance due to wear or the like, it is preferable that a plate-like member made of a material having excellent wear resistance is disposed instead of printed wiring.

  On the other hand, along with the downsizing of image forming apparatuses, there is a demand for further downsizing and lowering of the power supply unit. It has been. When such single-sided mounting is adopted, the other surface of the power supply substrate can be a GND surface (ground electrode). If the GND surface is arranged on the unit side (between the component mounting surface of the power supply board and the unit), it is possible to prevent noise generated on the component mounting surface side from propagating to the unit side. Also, in single-sided mounting, it is easy to assemble because components need only be mounted on one side of the board, and the number of assembly steps can be reduced. As a result, it is possible to reduce the manufacturing cost.

  Due to the recent miniaturization of surface mount components, even if the power supply board is mounted on one side, the board area has not increased significantly, and it is effective to adopt single-sided mounting when priority is given to reducing the height of the power supply unit. This is a technique. In addition, by adopting single-sided mounting, the power supply unit may be small in volume.

  However, when the connection structure of Patent Document 1 is applied to such a single-sided power supply board, it is necessary to provide a contact portion on the unit-side surface of the power supply board. For this purpose, the component mounting surface of the power supply board must be arranged on the unit side, or a contact part must be provided on the opposite side of the component mounting surface of the power supply board, and the opposite surface must be arranged on the unit side. In the former case, the opposite surface of the component mounting surface cannot be effectively used as a shield. In the latter case, it is necessary to mount the plate-shaped member on the opposite surface.

  The present invention has been made in view of such a conventional situation, and is suitable for reducing the height of a power supply unit, and can realize an excellent electrical connection and an electrical connection structure thereof An object of the present invention is to provide an image forming apparatus.

  In order to achieve the above-described object, the electrical connection structure according to the present invention employs the following technical means. First, the present invention presupposes an electrical connection structure that electrically connects an apparatus main body and a unit that is detachably attached to the apparatus main body. In the electrical connection structure according to the present invention, the unit-side contact provided in the unit and the body-side contact provided on the electrical board of the apparatus body are electrically connected by the elastic conductive member. The electrical board includes a through hole, and a main body side contact is provided on one surface of the electrical board in a state of straddling the opening of the through hole. The elastic conductive member has a first contact that contacts the body-side contact and a second contact that contacts the unit-side contact. The first contact and the second contact are electrically connected. The elastic conductive member is inserted into the through hole from the other surface side of the electrical board. In a state where the main body side contact and the first contact abut and the unit side contact and the second contact abut, the elastic conductive member urges the first contact to the main body side contact and the second contact to the unit. Energize to the side contact. The electrical connection structure includes a support restricting portion. The support restricting portion guides the first contact of the elastic conductive member to the main body side contact, supports the elastic contact member end of the first contact side, and restricts the first contact to a position facing the main contact.

  In this electrical connection structure, the elastic conductive member comes into contact with the main body side contact provided on the surface opposite to the unit side in the electrical board through the through hole provided in the electrical board. For this reason, all components including the contact member can be mounted on one surface of the electrical board. Further, since the first contact is held at the position facing the main body side contact by the support restricting portion, the unit is mounted on the apparatus main body, and the elastic conductive member urges the first contact to the main body side contact and Even when the two contacts are urged to the unit side contact, the first contact does not deviate from the main body side contact. In addition, since the support restricting portion supports the elastic conductive member end on the first contact side, the elastic conductive member does not fall down. Therefore, a good electrical connection can be realized.

  The support restricting portion may include a side surface of the through hole as a component. For example, the entire side surface of the through hole can be used as a component of the support restricting portion. In this case, the shape of the opening of the through hole may be a shape that can restrict the first contact to a position facing the main body contact. For example, the shape in which the shape of the cross section perpendicular to the insertion direction of the through hole at the first contact side end of the elastic conductive member is inscribed can be adopted as the opening shape. Further, the support restricting portion can be constituted by a part of the side surface of the through hole and a support member inserted into the through hole. In this case, as the opening shape of the elastic conductive member insertion portion defined by a part of the side surface of the through hole and the support member, a shape in which the cross-sectional shape of the elastic conductive member end is inscribed can be adopted. Note that the inscription includes a match. In addition, the term “inscribed” includes not only the case where the contact is completely made but also the substantial inscription in which the shape of the opening portion has a predetermined margin with respect to the cross-sectional shape of the elastic conductive member end.

  Moreover, in the above electrical connection structure, the main body side contact may have a fitting portion that fits with the elastic conductive member end on the first contact side. In this case, the support restricting portion includes the fitting portion as a component.

  In another aspect, the present invention also provides an image forming apparatus in which the apparatus main body and an image forming unit attached to the apparatus main body are electrically connected by the above electrical connection structure. it can.

  According to the present invention, it is possible to realize a good electrical connection to the contact provided on the surface of the electrical board opposite to the unit. Further, the present invention is effective for reducing the height of the power supply unit.

1 is a schematic configuration diagram showing the overall configuration of a multifunction machine according to an embodiment of the present invention. The figure which shows the hardware constitutions of the multifunctional device in one Embodiment of this invention. Sectional drawing which shows an example of the electrical connection structure in one Embodiment of this invention The figure which shows an example of the main body side contact in one Embodiment of this invention The figure which shows an example of the non-mounting surface of the electrical equipment board in one Embodiment of this invention The figure which shows an example of the support control part in one Embodiment of this invention. The figure which shows an example of the insertion member in one Embodiment of this invention The figure which shows the process of the electrical connection by the electrical connection structure in one Embodiment of this invention The figure which shows the other example of the support control part in one Embodiment of this invention. The figure which shows the other example of the insertion member in one Embodiment of this invention. The figure which shows the further another example of the support control part in one Embodiment of this invention. The figure which shows the other example of the main body side contact in one Embodiment of this invention The figure which expands and shows the other example of the main body side contact in one Embodiment of this invention The figure which expands and shows the other example of the main body side contact in one Embodiment of this invention. The figure which shows the modification of the insertion member in one Embodiment of this invention

  Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings. In the following embodiment, the present invention is embodied based on an example applied to a digital multifunction peripheral.

  FIG. 1 is a schematic configuration diagram illustrating an example of the overall configuration of a digital multifunction peripheral according to the present embodiment. As shown in FIG. 1, the multifunction peripheral 100 includes a main body 101 including an image reading unit 120 and an image forming unit 140, and a platen cover 102 attached above the main body 101. A document table 103 is provided on the upper surface of the main body 101, and the document table 103 is opened and closed by a platen cover 102. Further, the platen cover 102 includes a document conveying device 110.

  An image reading unit 120 is provided below the document table 103. The image reading unit 120 reads an image of a document with the scanning optical system 121 and generates digital data of the image. The document can be placed on the document table 103 or the document transport device 110. The scanning optical system 121 includes a first carriage 122, a second carriage 123, and a condenser lens 124. The first carriage 122 is provided with a linear light source 131 and a mirror 132, and the second carriage 123 is provided with mirrors 133 and 134. The light source 131 illuminates the document. The mirrors 132, 133, and 134 guide reflected light from the document to the condenser lens 124, and the condenser lens 124 forms an optical image on the light receiving surface of the line image sensor 125. In the scanning optical system 121, the first carriage 122 and the second carriage 123 are provided so as to be able to reciprocate in the sub-scanning direction 135. By moving the first carriage 122 and the second carriage 123 in the sub-scanning direction 135, the image of the document placed on the document table 103 can be read by the image sensor 125. When reading an image of a document set on the document conveying device 110, the image reading unit 120 temporarily fixes the first carriage 122 and the second carriage 123 according to the image reading position, and passes the image reading position. Are read by the image sensor 125. The image sensor 125 generates image data of a document corresponding to, for example, each color of R (red), G (green), and B (blue) from the light image incident on the light receiving surface.

  The image forming unit 140 prints image data obtained by the image reading unit 120 or image data received from another device (not shown) connected to the network 162 via the network adapter 161 on a sheet. The image forming unit 140 includes a photosensitive drum 141. The photosensitive drum 141 rotates in one direction at a constant speed. Around the photosensitive drum 141, a charger 142, an exposure unit 143, a developing unit 144, and an intermediate transfer belt 145 are arranged in this order from the upstream side in the rotation direction. The charger 142 uniformly charges the surface of the photosensitive drum 141. The exposure device 143 irradiates the surface of the uniformly charged photoconductor drum 141 with light according to the image data, and forms an electrostatic latent image on the photoconductor drum 141. The developing device 144 attaches toner to the electrostatic latent image and forms a toner image on the photosensitive drum 141. The intermediate transfer belt 145 transfers the toner image on the photosensitive drum 141 onto a sheet. When the image data is a color image, the intermediate transfer belt 145 transfers each color toner image onto the same sheet. The RGB color image is converted into C (cyan), M (magenta), Y (yellow), and K (black) format image data, and the image data of each color is input to the exposure unit 143.

  The image forming unit 140 feeds paper from the manual feed tray 151, the paper feed cassettes 152, 153, and 154 to the transfer unit between the intermediate transfer belt 145 and the transfer roller 146. Various sizes of paper can be placed or stored in the manual feed tray 151 and the paper feed cassettes 152, 153, and 154. The image forming unit 140 selects a sheet specified by the user or a sheet corresponding to the automatically detected document size, and pulls out the selected sheet from the manual feed tray 151 and the cassettes 152, 153, and 154 by the feeding roller 155. The pulled-out paper is sent to the transfer unit by the conveyance roller 156 and the registration roller 157. The sheet on which the toner image is transferred is conveyed to the fixing device 148 by the conveyance belt 147. The fixing device 148 has a fixing roller 158 and a pressure roller 159 with a built-in heater, and fixes the toner image on the sheet by heat and pressing force. The image forming unit 140 discharges the sheet that has passed through the fixing device 148 to the discharge tray 149.

  The user can use the operation panel 200 provided on the upper front of the main body to give a copy start or other instruction to the multi-function device 100 as described above, or to check the status and settings of the multi-function device 100. .

  In the multi-function device 100, the photosensitive drum 141, the charging device 142, the exposure device 143, the developing device 144, the intermediate transfer belt 145, the transfer roller 146, and the fixing device 148 are combined together or unitized. Each unit is detachably attached to the main body 101. At the time of failure occurrence or maintenance, the unit is detached from the main body 101, and inspection, replacement, etc. are performed. When these units are mounted on the main body 101, an electric path through which power is supplied from the main body 101 by an electrical connection structure described later and an output signal of a sensor (detector) provided on the unit side are sent to the main body 101. An electrical path for notification is established.

  FIG. 2 is a hardware configuration diagram of a control system in the multifunction machine. The multifunction peripheral 100 according to the present embodiment includes a CPU (Central Processing Unit) 201, a RAM (Random Access Memory) 202, a ROM (Read Only Memory) 203, an HDD (Hard Disk Drive) 204, an original transport device 110, and an image reading unit 120. A driver 205 corresponding to each drive unit in the image forming unit 140 is connected via an internal bus 206. The ROM 203, the HDD 204, and the like store programs, and the CPU 201 controls the multifunction peripheral 100 in accordance with instructions from the control program. For example, the CPU 201 uses the RAM 202 as a work area, and controls the operation of each driving unit by exchanging data and commands with the driver 205. The HDD 204 is also used to store image data obtained by the image reading unit 120 and image data received from other devices through the network adapter 161.

  An operation panel 200 and various sensors 207 are also connected to the internal bus 206. The operation panel 200 receives a user operation and supplies a signal based on the operation to the CPU 201. The sensor 207 includes various sensors such as an open / close detection sensor for the platen cover 102, a document detection sensor on the document table 103, a temperature sensor for the fixing device 148, and a detection sensor for the conveyed paper or document. For example, the CPU 201 executes a program stored in the ROM 203 to control the operation of each unit in accordance with signals from these sensors.

  FIG. 3 is a cross-sectional view showing an example of the above-described electrical connection structure. As shown in FIG. 3, the electrical connection structure 10 is an elastic member that electrically connects a unit-side contact 21 provided in the unit 20 and a body-side contact 31 provided on the electrical board 30 of the apparatus body 101. A conductive member 40 is provided.

  The electrical board 30 is a circuit board that establishes an electrical connection with the unit 20 mounted on the main body 101. For example, the power board that supplies power to the unit 20 or an output signal of a sensor provided in the unit 20 is used. Including a signal processing board. In the present embodiment, the electrical component board 30 has components mounted only on one surface 30a (hereinafter referred to as a mounting surface 30a), and members constituting the main body side contact 31 are also mounted on the mounting surface 30a side. . In the present embodiment, the metal pattern is disposed on substantially the entire other surface 30b (hereinafter referred to as the non-mounting surface 30b) of the electrical substrate 30. When the electrical board 30 is mounted on the main body 101, a ground potential is applied to the metal pattern and functions as a GND surface. As will be described later, when an electrical inconvenience such as a short circuit occurs when the ground potential is applied to the non-mounting surface 30b due to the mounting component including a lead portion penetrating the electrical component board 30 or the like, this portion Is electrically separated from the metal pattern.

  The elastic conductive member 40 includes a two-stage conductive compression coil spring in which a large diameter portion 41 and a small diameter portion 42 are continuous. The tip of the elastic conductive member 40 on the large diameter portion 41 side functions as a first contact that contacts the main body side contact 31. The tip of the elastic conductive member 40 on the small diameter portion 42 side functions as a second contact that contacts the unit side contact 21. Hereinafter, the tip of the elastic conductive member 40 on the large-diameter portion 41 side will be described as a first contact, and the tip of the elastic conductive member 40 on the small-diameter portion 42 side will be described as a second contact.

  The end portion on the large diameter portion 41 side of the elastic conductive member 40 is inserted into the through hole 32 from the non-mounting surface 30 b of the electrical board 30, and the tip thereof abuts on the main body side contact 31. Thereby, the main body side contact 31 and the elastic conductive member 40 are electrically connected. The elastic conductive member 40 can be made of a conductive elastic wire such as phosphor bronze or stainless steel. Note that the end portion of the elastic conductive member 40 does not mean only the tip (first contact) of the elastic conductive member 40, but the portion of the elastic conductive member 40 that enters the through hole 32 and the portion that can be substantially identified. Including neighboring parts.

  In addition to the above, the electrical connection structure 10 guides the first contact of the elastic conductive member 40 to the main body side contact 31 and supports the end of the elastic conductive member 40 on the large diameter portion 41 side. A support restricting portion 50 that restricts the side contact 31 to a position facing it is provided. The detailed structure of the support restricting unit 50 will be described later.

  In the present embodiment, a conductive compression coil spring is employed as the elastic conductive member 40, but the elastic conductive member 40 is not limited to this. The elastic conductive member 40 includes a first contact that contacts the body-side contact 31 and a second contact that contacts the unit-side contact 21 and is electrically connected to the first contact. A structure in which the first contact is urged to the main body side contact 31 and the second contact is urged to the unit side contact 21 in a state where one contact is in contact and the unit side contact 21 and the second contact are in contact. If it is. For example, a coil spring having pin-shaped conductive terminals on both ends, which are contacts, a coil spring having pin-shaped conductive terminals only on one contact, or a pin having coil springs functioning as contacts on both ends. However, the same effect can be obtained. Moreover, the elastic body which produces the urging force is not limited to the coil spring, and other compression springs can be used. Further, use other than compression springs such as torsion coil springs and leaf springs is not excluded. Furthermore, it is also possible to use an elastic body other than a spring as long as the same effect is obtained.

  FIG. 4 is a schematic diagram showing a main body side contact of the electrical connection structure. FIG. 5 is a diagram showing a non-mounting surface of the electrical board shown in FIG. In this example, the main body side contact 31 is composed of a U-shaped pin terminal 31a bent in a state where both ends are substantially parallel to the same direction. As shown in FIGS. 4 and 5, both end portions of the pin terminal 31a function as lead portions 31b. The lead part 31b is inserted into a through hole 33 for fixing the pin terminal 31a provided on the electrical board 30 and is fixed by solder or the like. The pin terminal 31 a is provided on the mounting surface 30 a side of the electrical board 30 in a state straddling the through hole 32 provided in the electrical board 30. Here, the main body side contact 31 is constituted by two pin terminals 31a arranged in parallel with each other. The straight portion 31 c of the pin terminal 31 a that is disposed substantially parallel to the surface of the electrical board 30 is disposed to face the opening of the through hole 32. The direction of the pin terminal 31a is determined according to the arrangement of the power supply wiring pattern 34 on the mounting surface 30a. The through-hole 33 is provided in the wiring pattern 34 of the electrical board 30, and a predetermined potential is applied to each pin terminal 31 a through the wiring pattern 34.

  When a ground potential is applied to the lead portion 31b of the pin terminal 31a on the non-mounting surface 30b of the electrical board 30, a short circuit is caused. Therefore, the portion of the through hole 33 in the non-mounting surface 30b is electrically separated from the metal pattern 35 (hereinafter referred to as the GND surface 35) as shown in FIG. Similarly, in order to avoid a short circuit between the elastic conductive member 40 inserted into the through hole 32 and the GND surface 35, a region where the GND surface 35 is not disposed is also provided around the through hole 32. Instead of the pin terminal 31a having the lead portion 31b, a surface mount type pin terminal whose end is fixed to the surface of the mounting surface 30a may be used.

FIG. 6 is a schematic diagram illustrating an example of a support restricting portion of the electrical connection structure. In this example, the support restricting portion 50 is a support member that is a part of the insertion member 51 that is inserted into the through-hole 32 of the electrical board 30 from the non-mounting surface 30b side (the inner side surfaces 52a of the pair of opposing protrusions 52). ) And a part of the side surface of the through-hole 32 (in FIG. 6, the side surface 32a located on the upper side and the side surface 32b located on the lower side). As shown in FIG. 6, the through-hole 32 has an arrow-shaped outer shape in plan view, and a short-side interval having substantially parallel side surfaces facing each other is w <b> 1. This interval w1 is a value obtained by adding a margin σ _A to the outer diameter W _A of the elastic conductive member 40 at the end on the large diameter portion 41 side. The margin σ _A is set in consideration of the processing variation of the insertion member 51 and the outer diameter variation of the elastic conductive member 40 at the end on the large diameter portion 41 side. Specifically, a margin as small as possible is set so that expansion and contraction of the elastic conductive member 40 is not hindered by contact and the first contact side end of the elastic conductive member 40 can be inserted into the through hole 32. . Moreover, in this example, the maximum opening width in the longitudinal direction of the through hole 32 that coincides with the direction of the arrow is w2, which is larger than w1.

  FIG. 7 is a diagram showing the structure of the insertion member 51 in more detail. FIG. 7A is a view showing the opposite surface that is inserted into the through hole 32 of the insertion member 51. 7B is a side view when FIG. 7A is a front view, and FIG. 7C is a plan view when FIG. 7A is a front view. FIG. 7D is a diagram illustrating a state where the insertion member 51 is inserted into the electrical board 30. In addition, FIG.7 (d) is the figure seen from the same direction as FIG.7 (c).

  As shown in FIGS. 7A to 7C, the insertion member 51 has a hollow columnar structure including a through hole 53 in the axial direction, and is formed at the end of the columnar body 55 on the through hole insertion side. A pair of opposing protrusions 52 functioning as support members are provided. In this example, the insertion member 51 is made of an insulating material such as resin. The inner side surfaces 52a of the protrusions 52 facing each other are flat, and the interval is set to w1. The length of the protrusion 52 (projection length) is the same as the distance from the non-mounting surface 30 b of the electrical board 30 to the straight portion 31 c of the main body side contact 31. In FIG. 7B, the width of the tip of the protrusion 52 is w3 smaller than w1, so that it can be reliably inserted into the through hole 32. In addition, although the opening diameter of the through-hole 53 of the cylindrical main body 55 is also w1 here, the said opening diameter can be made larger than w1.

  Moreover, as shown in FIG.7 (c), the notch 54 is provided in the cylindrical main body 55 between the protrusions 52 which oppose. The notch 54 accommodates the lead portion 32b of the pin terminal 31a that protrudes toward the non-mounting surface 30b when the protrusion 52 is inserted into the through hole 32 of the electrical board 30 as shown in FIG. 7 (d). To do. Thereby, the insertion member 51 is aligned with the main body side contact 31. Although not particularly limited, in this example, the notch width of the notch 54 is set to an interval w4 in which the lead portion 32b of the pin terminal 31a is press-fitted. The insertion member 51 is fixed to the electrical board 30 by the press fitting.

  As shown in FIG. 6, when the protrusion 52 of the insertion member 51 is inserted into the through hole 32 of the electrical component board 30, the length of one side is determined by the inner side surface 52 a of the protrusion 52 and the side surfaces 32 a and 32 b facing the through hole 32. A support restricting portion 50 composed of a square region having a length of w1 is configured. That is, when the first contact side end portion of the elastic conductive member 40 is inserted into the through hole 53 of the insertion member 51 from the non-mounting surface 30b side of the electrical circuit board 30 in this state, the first contact is a support restricting portion formed of the square region. The elastic conductive member 40 is regulated to a position where the first contact and the main body side contact 31 face each other by being guided by the main body side contact 31 by being inserted through 50. Further, since the side surface of the first contact side end portion of the elastic conductive member 40 is supported by the support restricting portion 50, the inserted elastic conductive member 40 does not fall down. Therefore, since the first contact and the main body side contact 31 are prevented from coming into contact with the elastic conductive member 40 in a tilted state, a good electrical connection can always be realized. Further, in the electrical connection structure 10, the elastic conductive member 40 is brought into contact with the main body side contact 31 provided on the surface opposite to the unit 20 side in the electrical board 30 through the through hole 32 provided in the electrical board 30. For this reason, all the components including the contact member can be mounted on one surface of the electrical board 30, which contributes to a reduction in the height of the power supply unit. In the above example, since the opening diameter of the through hole 53 of the insertion member 51 is also w1, the through hole 53 also functions as a part of the support restricting portion 50. However, the opening diameter of the through hole 53 is not limited. Even if is larger than w1, good electrical connection can be realized.

  FIG. 8 is a diagram illustrating a process of electrical connection between the electrical board and the unit using the electrical connection structure. As shown in FIG. 8A, the protrusion 52 of the insertion member 51 is inserted into the through hole 32 of the electrical board 30 from the non-mounting face 30 b side of the above-described electrical board 30 provided with the main body side contact 31 on the mounting face 30 a. Then, the insertion member 51 is fixed to the electrical board 30. Next, as shown in FIG. 8B, the first contact side end of the elastic conductive member 40 is inserted into the through hole 32 of the electrical board 30 from the non-mounting surface 30 b side of the electrical board 30. Thereby, the side surface of the first contact side end portion of the elastic conductive member 40 is supported by the above-described support restricting portion 50, and the first contact point of the elastic conductive member 40 is held at a position facing the main body side contact 31. The electrical board 30 is attached to the main body 101 of the multifunction machine 100 in this state.

  In the process of mounting the unit 20 on the main body 101, as shown in FIG. 8C, the unit-side contact 21 is positioned to face the tip (second contact) on the small-diameter portion 42 side of the elastic conductive member 40. . When the unit 20 is properly attached to the main body 101, the unit side contact 21 and the second contact of the elastic conductive member 40 come into contact with each other, and the elastic conductive member 40 is compressed. As a result, the elastic conductive member 40 is in a state of urging the first contact toward the main body side contact 31 and urging the second contact toward the unit side contact 21, and the electrical contact between the main body side contact 31 and the unit side contact 21. Connection is established.

  In the above, the case where the support restricting portion 50 is configured by the side portions 32a and 32b of the through hole 32 and the protrusion 52 inserted into the through hole 32 has been described. It is also possible to adopt the configuration.

  FIG. 9 is a schematic diagram showing another configuration of the support restricting portion of the present embodiment. In this example, the support restricting portion 50 includes a support member (inner side surface 62a of the protrusion 62) that is a part of the insertion member 61 that is inserted into the through hole 35 of the electrical board 30 from the non-mounting surface 30b side, and the through hole 35. 9 (in FIG. 9, the side surface 35a located on the upper side, the side surface 35b located on the lower side, and the side surface 35c located on the left side). As shown in FIG. 9, the through-hole 35 has an arrow-shaped outer shape in plan view, and the interval in the short direction having the substantially parallel side surfaces facing each other is the aforementioned w1. In this example, in the arrow direction, the distance from the intermediate position of the two pin terminals 31a to the side surface 35c is half of w1 (w1 / 2).

  FIG. 10 is a diagram showing the structure of the insertion member 61 in more detail. FIG. 10A is a view showing the opposite surface that is inserted into the through hole 35 of the insertion member 61. 10B is a side view when FIG. 10A is a front view, and FIG. 10C is a plan view when FIG. 10A is a front view. FIG. 10D is a diagram showing a state where the insertion member 61 is inserted into the electrical board 30. In addition, FIG.10 (d) is the figure seen from the same direction as FIG.10 (c).

  As shown in FIGS. 10A to 10C, the insertion member 61 has a hollow columnar structure including a through hole 63 in the axial direction, and is formed at the end of the columnar body 65 on the through hole insertion side. One protrusion 62 that functions as a support member is provided. In this example, the insertion member 61 is made of an insulating material such as resin. The inner surface 62a of the protrusion 62 is a flat surface, and the distance from the axial center of the cylindrical main body 65 to the inner surface 62a is set to half of w1 (w1 / 2). In FIG. 10B, the width of the tip of the protrusion 62 is w3 smaller than w1, so that the protrusion 62 can be reliably inserted into the through hole 35. In addition, although the opening diameter of the through-hole 63 of the cylindrical main body 65 is also w1 here, the said opening diameter can be made larger than w1.

  Further, as shown in FIG. 10C, the cylindrical body 65 of the insertion member 61 is also provided with a notch 64 similar to the insertion member 51. The notch 64 accommodates the lead portion 32b of the pin terminal 31a protruding toward the non-mounting surface 30b when the protrusion 62 is inserted into the through hole 35 of the electrical board 30 as shown in FIG. To do. Although not particularly limited, in this example, the notch width of the notch 64 is set to an interval w4 in which the lead portion 32b of the pin terminal 31a is press-fitted, and the insertion member 61 is fixed to the electrical board 30 by the press-fitting. .

  As shown in FIG. 9, when the protrusion 62 of the insertion member 61 is inserted into the through hole 35 of the electrical component board 30, the inner side surface 62 a of the protrusion 62, the side surfaces 35 a, 35 b and the side surface 35 c of the through hole 35 are A support restricting portion 50 composed of a square region having a side length w1 is formed. That is, when the first contact side end portion of the elastic conductive member 40 is inserted into the through hole 63 of the insertion member 61 from the non-mounting surface 30b side of the electrical circuit board 30 in this state, the first contact point is a support restricting portion made of the square region. The elastic conductive member 40 is regulated at a position where the first contact and the main body side contact 31 face each other by being guided by the main body side contact 31. Therefore, the same effect as when the insertion member 51 is employed can be obtained. In the above-described example, since the opening diameter of the through hole 63 of the insertion member 61 is also w <b> 1, the through hole 63 also functions as a part of the support regulating portion 50. However, even when the opening diameter of the through-hole 63 is larger than w1, good electrical connection can be realized.

  As described above, the support restricting portion 50 includes the part of the side surface of the through hole 32 (35) provided in the electrical board 30 and the support members (projections 52 and 62) inserted into the through hole 32 (35). However, it is also possible to configure the support restricting portion 50 only by the side surface of the through hole.

  FIG. 11 is a schematic diagram illustrating an example in which the support restricting portion is configured only by the side surface of the through hole. In this example, the electrical board 30 is provided with a square through-hole 36 whose one side is w1 described above. That is, when the first contact side end portion of the elastic conductive member 40 is inserted into the through hole 36 from the non-mounting surface 30 b side of the electrical circuit board 30, the first contact is inserted into the support restricting portion 50 formed of the side surface of the through hole 36. As a result, the elastic conductive member 40 is regulated to a position where the first contact and the main body side contact 31 face each other. Therefore, as in the case where the above-described insertion members 51 and 61 are employed, it is possible to prevent the distal end on the large diameter portion 41 side and the main body side contact 31 from coming into contact with the elastic conductive member 40 being inclined. In this case, the ratio (aspect ratio d / w1) between the opening width (opening diameter) of the through hole 36 and the distance d from the non-mounting surface 30b of the electrical board 30 to the straight portion 31c of the main body side contact 31 is as follows. If it becomes extremely large, the possibility that the elastic conductive member 40 enters between the electrical board 30 and the main body side contact 31 increases. Therefore, the aspect ratio is preferably 5 or less.

  As described above, the first contact point of the elastic conductive member is guided to the main body side contact, the elastic contact member end portion on the first contact side is supported, and the first contact is restricted to the position facing the main body side contact. By configuring the restricting portion with the whole side surface of the through hole of the electrical board or a part of the side surface of the through hole and the support member inserted into the through hole, it is possible to always achieve a good electrical connection. it can. In particular, when the support restricting portion is constituted by a part of the side surface of the through hole and the support member inserted into the through hole, the opening shape of the electric circuit board provided to face the main body side contact is used as the end of the elastic conductive member. A shape different from the cross-sectional shape can be adopted. Therefore, the degree of freedom in designing the electrical board can be increased.

  Further, in this configuration, the elastic conductive member comes into contact with the main body side contact provided on the surface opposite to the unit side in the electrical board through the through hole provided in the electrical board. For this reason, all the components including the contact member can be mounted on one surface of the electrical board, which can contribute to a reduction in the height of the power supply unit. Further, the GND surface can be disposed between the electrical board and the unit, and the propagation of noise generated on the component mounting surface side to the unit side can also be prevented.

  In the above, the shape of the cross section perpendicular to the insertion direction to the through hole of the first contact side end portion of the elastic conductive member is circular, and the opening shape of the through hole, which is the support regulating portion, or the through hole A square was adopted as the opening shape of the elastic conductive member insertion portion defined by a part of the side surface and the support member. However, any shape can be adopted as the opening shape as long as the cross-sectional shape of the first contact side end portion of the elastic conductive member is inscribed. That is, the cross-sectional shape is not limited to a quadrangle, and may be another polygon. Moreover, it is not essential that the inner side surface of the opening portion is a flat surface, and a curved surface or a surface having irregularities may be used. Therefore, in the above-described case, a circle that matches the cross-sectional shape of the first contact side end portion of the elastic conductive member can be adopted as the opening shape. Similarly, when the cross-sectional shape of the first contact side end portion of the elastic conductive member is a polygon, the shape inscribed by the cross-sectional shape can be employed as the opening shape. In addition, in any case of adopting any opening shape, the combination of the through-hole side surface of the electrical board and the support member constituting the opening shape is also arbitrary. Note that the inscribed part includes a match, and the inscribed part has a margin that allows the shape of the opening portion to be allowed from the viewpoint of electrical connection with respect to the cross-sectional shape of the elastic conductive member end. Including cases.

  In the above, as a particularly preferable form, the length of the protrusion of the insertion member is the distance from the non-mounting surface of the electrical board to the main body side contact, but at least the non-mounting surface of the electrical board functions as a support regulating portion. It is only necessary that the opening to be configured can be configured. Even in this case, it is possible to obtain the same effect as the case where the support restricting portion is configured only by the side surface of the above-described through hole.

  Further, in the above, the insertion member is fixed to the electrical board by press-fitting the lead portion of the pin terminal protruding on the non-mounting surface of the electrical board into the notch of the insertion member, but the structure for fixing the insertion member to the electrical board is Is optional. For example, in the example shown in FIGS. 6 and 9, the width of the protrusions 52 and 62 is made larger than w1 which is the opening width of the through holes 32 and 35, and the protrusion is press-fitted into the through hole, so that the insertion member is electrically mounted. You may fix to a board | substrate. Further, the insertion member may be fixed to the electrical board via a support member fixed to the electrical board or a support part extending from, for example, a cylindrical body of the insertion member.

  By the way, the support regulation part can also contain a main body side contact as a component. For example, the main body side contact has a fitting portion that fits with the elastic conductive member end on the first contact side, and the fitting portion guides the first contact of the elastic conductive member to the main body side contact and It is possible to adopt a configuration in which the elastic contact member end on the one contact side is supported and the first contact is restricted to a position facing the main body contact.

  FIG. 12 is a schematic diagram illustrating an example of a support restricting unit including a main body side contact as a constituent element. In this example, the main body side contact 71 is bent in a state where both ends are substantially parallel to each other in the same direction, and a protrusion 31e is further provided on the straight portion 31c of the U-shaped pin terminal 31a. And a convex pin terminal 31d provided. Both end portions of the pin terminals 31a and 31d function as lead portions. The lead portion is inserted into a through hole for fixing a pin terminal provided on the electrical board 30 and is fixed by solder or the like. The pin terminals 31 a and 31 d are provided on the mounting surface 30 a side of the electrical board 30 in a state of straddling the through holes 32 provided in the electrical board 30. Here, the main body side contact 71 is constituted by two pin terminals 31a arranged in parallel with each other and the pin terminal 31d arranged in parallel with the two pin terminals 31a. The straight portion 31c of the pin terminal 31a arranged substantially parallel to the surface of the electrical board 30, the protrusion 31e of the pin terminal 31d, and the base end 31f of the protrusion 31e face the opening of the through hole 32. Arranged. The pin terminal fixing through-hole is provided in the wiring pattern 34 of the electrical board 30, and a predetermined potential is applied to the pin terminals 31 a and 31 d through the wiring pattern 34.

  FIG. 13 is an enlarged view of the main body side contact shown in FIG. FIG. 13A is a cross-sectional view taken along the pin terminal 31d of the main body side contact 71, and FIG. 13B is a diagram showing only the pin terminals 31a and 31d of the main body side contact 71 viewed from the mounting surface 30a side. is there. As shown in FIG. 13A, the base end portion 31f of the pin terminal 31d has the same height as the straight portions 31c of the pin terminals 31a on both sides. That is, the linear portion 31c of both pin terminals 31a and the base end portion 31f of the pin terminal 31d are in the same plane, and the protrusion 31e of the pin terminal 31d protrudes from the plane. Further, as shown in FIGS. 13A and 13B, the interval between the opposed inner ends of both pin terminals 31a and the interval between the opposed inner ends of the protrusion 31e are set to the above-described w1.

  According to this configuration, a square region having a side w1 is formed between the inner ends facing each other of the pin terminals 31a and the inner ends facing each other of the protrusion 31e. That is, the main body side contact 71 is configured with a fitting portion that fits with the first contact side end of the elastic conductive member 40. The fitting portion guides the first contact of the elastic conductive member 40 to the main body side contact 71 and supports the first contact side end of the elastic conductive member end 40, and the first contact and the main body side contact 71. Functions as a support restricting portion 50 that restricts the elastic conductive member end portion 40 at a position facing each other.

  When the first contact side end of the elastic conductive member 40 is inserted into the through-hole 32 from the non-mounting surface 30b side with respect to the electrical board 30 having the main body side contact 71, the first contact side end is Fits into the joint. Therefore, as in the above-described cases, the contact between the first contact and the main body side contact 71 when the elastic conductive member 40 is tilted is prevented. In addition, it cannot be overemphasized that the said structure can be arbitrarily combined with each above-mentioned example, and can comprise a support control part. By combining in this way, an effect can be obtained regardless of the above aspect ratio.

  FIG. 14 is an enlarged view showing another main body side contact capable of producing the same effect as the main body side contact shown in FIGS. 12 and 13. The body-side contact 81 includes a U-shaped pin terminal 31a and a pin terminal 31g provided with a bent portion 31h protruding toward the lead portion at a portion corresponding to the linear portion 31c of the U-shaped pin terminal 31a. Similar to the example illustrated in FIG. 12, the pin terminals 31 a and 31 g are provided on the mounting surface 30 a side of the electrical board 30 in a state of straddling the through holes 32 provided in the electrical board 30. Here, between the two pin terminals 31a arranged in parallel with each other and the two pin terminals 31a, the pin terminal 31g is arranged in parallel with them. The straight portion 31c of the pin terminal 31a that is arranged substantially parallel to the surface of the electrical board 30 and the bent portion 31h and the base end portion 31i of the pin terminal 31g are arranged to face the opening of the through hole 32. . Both end portions of the pin terminals 31a and 31g are inserted into through holes for fixing the pin terminals provided in the electrical board 30 and are fixed by solder or the like. 14A is a cross-sectional view taken along the pin terminal 31g of the main body side contact 81, and FIG. 14B shows only the pin terminals 31a and 31g of the main body side contact 81 viewed from the mounting surface 30a side. FIG.

The distance between the base end portion 31i of the bent portion 31h of the pin terminal 31g and the lead portion distal end is larger than the distance between the straight portion 31c of the pin terminal 31a and the lead portion distal end. Therefore, when mounted on the electrical board 30, as shown in FIG. 14A, the base end portion 31 i is located farther from the mounting surface 30 a than the linear portion 31 c of the pin terminal 31 a. That is, the straight portions 31c of both pin terminals 31a are in the same plane, and the base end portion 31i of the pin terminal 31g protrudes from the plane. Further, as shown in FIGS. 14A and 14B, the interval between the opposing inner ends of both pin terminals 31a is set to the above-described w1, and the bending width of the bent portion 31h at the proximal end portion 31i is set. Is set to w5. The width w5 is a value obtained by adding a margin sigma _B to the inner diameter W _B of the first contact end portion of the elastic conductive member 40. The margin σ _B is set in consideration of the inner diameter variation of the first contact side end portion of the elastic conductive member 40. Specifically, a margin as small as possible is set so that the bent portion 31 h can be fitted to the first contact side end of the elastic conductive member 40.

  According to this configuration, a fitting portion that fits with the first contact side end portion of the elastic conductive member 40 is formed on the main body side contact 81 by the inner side end of the both pin terminals 31a and the bent portion 31h. . The fitting portion guides the first contact of the elastic conductive member 40 to the main body side contact 81 and supports the first contact side end of the elastic conductive member end 40, and the first contact and the main body side contact 81. Functions as a support restricting portion 50 that restricts the elastic conductive member end portion 40 at a position facing each other.

  When the first contact side end of the elastic conductive member 40 is inserted into the through-hole 32 from the non-mounting surface 30b side with respect to the electrical circuit board 30 including the main body side contact 81, the first contact side end is Fits into the joint. Therefore, as in the above-described cases, the contact between the first contact and the main body side contact 81 in the state where the elastic conductive member 40 is inclined is prevented. In addition, it cannot be overemphasized that the said structure can be arbitrarily combined with each above-mentioned example, and can comprise a support control part. By combining in this way, an effect can be obtained regardless of the above aspect ratio. In the above description, the bent shape of the bent portion 31h is a triangular shape, but other shapes such as a rectangular shape may be used as long as the shape can be fitted to the inner surface of the first contact side end portion of the elastic conductive member 40. Good.

  As described above, even when the support restricting portion including the main body side contact as a constituent element is employed, it is possible to prevent the first contact and the main body side contact from coming into contact with the elastic conductive member in an inclined state. Good electrical connection can always be realized.

  The above-described embodiments do not limit the technical scope of the present invention, and various modifications and applications other than those already described are possible within the scope of the present invention. For example, in the above description, the main body side contact is constituted by two or three pin terminals. However, the number can be arbitrarily changed within a range in which the same effect is obtained. In addition, the main body side contacts may be configured as an integral member within a range where the same effects can be obtained.

  According to the present invention, since the elastic conductive member does not tilt with respect to the main body side contact, the elastic conductive member is unlikely to buckle when the elastic conductive member compressively deforms when the unit is mounted. However, if the distance between the first contact and the second contact of the elastic conductive member becomes extremely large, the elastic conductive member may be buckled during the compression deformation of the elastic conductive member. From the viewpoint of preventing such buckling, it is preferable to provide a guide for preventing buckling of the elastic conductive member. Such a guide may be provided as an independent member. However, as shown in FIG. 15, an insertion member 91 having a columnar body 95 that is long in the axial direction is employed, and the through hole 93 of the columnar body 95 is used as a guide. May be used. According to such an insertion member 91, due to a synergistic effect with the protrusion 92, contact between the first contact and the main body side contact 31 in a state where the elastic conductive member 40 is inclined can be prevented, and a good electrical connection can be achieved. Can be realized.

  In addition, in the above-described embodiment, the present invention is embodied as a digital multifunction peripheral. However, the present invention can be applied not only to a digital multifunction peripheral but also to any image forming apparatus such as a printer or a copier. .

  According to the present invention, good electrical connection can be realized, which is useful as an electrical connection structure and an image forming apparatus.

DESCRIPTION OF SYMBOLS 10 Electrical connection structure 20 Unit 21 Unit side contact 30 Electrical board 31 Main body side contact 32, 35, 36 Through-hole 32a, 32b, 32c Through-hole side surface 40 Elastic conductive member 41 Large diameter part 42 Small diameter part 50 Support control part 51, 61, 91 Insertion member 52, 62 Projection (support member)
52a, 62a Protrusion inner surface 100 MFP 110 Document transport device 120 Image reading unit 130 Image forming unit 200 Operation panel

Claims (5)

An electrical connection structure for electrically connecting the apparatus main body and a unit that is detachably attached to the apparatus main body,
A unit-side contact provided in the unit;
An electrical board provided in the apparatus body;
A through hole provided in the electrical board;
A main body side contact provided on one surface of the electrical board in a state straddling the opening of the through hole,
The first contact that contacts the body-side contact, and the second contact that is electrically connected to the first contact and contacts the unit-side contact, and from the other surface side of the electrical board to the through hole The first contact is urged toward the body-side contact while the body-side contact and the first contact are in contact with each other, and the unit-side contact and the second contact are in contact with each other. An elastic conductive member for urging the second contact toward the unit-side contact;
The first contact point of the elastic conductive member is guided to the main body side contact, and the elastic conductive member end portion on the first contact side is supported, and the first contact is restricted to a position facing the main body side contact. , The support regulation department,
Electrical connection structure comprising.   The electrical connection structure according to claim 1, wherein the support restricting portion includes a side surface of the through hole.   The electrical connection structure according to claim 2, wherein the support restricting portion includes a part of a side surface of the through hole and a support member inserted into the through hole. The main body side contact has a fitting portion that fits with the elastic conductive member end on the first contact side,
The electrical connection structure according to claim 1, wherein the support restricting portion includes the fitting portion.   5. An image forming apparatus in which the apparatus main body and the image forming unit mounted on the apparatus main body are electrically connected by the electrical connection structure according to claim 1.

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