JP2024071476A - Photoelectric switch and sensor unit - Google Patents

Abstract

[Problem] To provide a signal cable connection structure capable of ensuring a sufficient display area for a display in a photoelectric switch. [Solution] A photoelectric switch has a housing having a substantially rectangular parallelepiped shape. A display 5 is provided on a first surface of the housing and has a display area. A signal cable 51 connects a control board and the display 5. The display 5 has a connection portion 70a that is connected to the signal cable 51. The connection portion 70a is disposed between the display area and the signal cable in the longitudinal direction of the housing. This provides a signal cable 51 connection structure capable of ensuring a sufficient display area for the display 5 in the photoelectric switch. [Selected Figure] Figure 7

Description

The present invention relates to a photoelectric switch and a sensor unit.

Products (workpieces) produced in a factory are transported by a transport device such as a conveyor belt, and their arrival at a designated location is detected by a photoelectric switch. A photoelectric switch generally projects light toward a workpiece, receives the light reflected from the workpiece, and displays a numerical value indicating the amount of light received and a threshold value with which this numerical value is compared on a seven-segment display (Patent Document 1). When the photoelectric switch detects a workpiece based on the amount of light received and the threshold value, it outputs an ON signal indicating detection.

JP 2003-141961 A

Thus, a photoelectric switch is a relatively simple sensor that outputs a detection signal indicating whether or not a workpiece is detected. For this reason, seven-segment displays have been used as indicators for many years. Photoelectric switches that do not have an indicator that displays a numerical value still exist. However, in recent years, as photoelectric switches have become more sophisticated, seven-segment displays are no longer able to provide sufficient information to users. Therefore, the inventor of the present application considered adopting a dot matrix indicator such as an OLED (organic light-emitting diode). A dot matrix display has many wirings (gate lines, signal lines, power lines, and ground lines), and displays information by turning on/off semiconductor switches arranged at the intersections of these. The many wirings are connected to a controller via an FPC cable. The problem here is the shape of the housing of the photoelectric switch. In a factory, many photoelectric switches are connected to a DIN (German Institute for Standardization) rail, so the shape of the photoelectric switch is long and thin, approximately a rectangular parallelepiped. Therefore, the top surface of the photoelectric switch on which the indicator is attached is also long and thin. This limits the length of the short side of the indicator. As mentioned above, dot matrix displays have many wires, so unless you think carefully about where to connect them to the FPC (flexible printed circuit) cable, it is difficult to ensure a sufficient display area.

The present invention aims to provide a signal cable connection structure that ensures a sufficient display area for the display in a photoelectric switch.

The present invention relates to, for example,
A detection unit for detecting a physical quantity from a detection target;
A housing having a substantially rectangular parallelepiped shape;
a display device that includes an OLED layer functioning as a display layer and a rectangular transparent member and is provided on a first surface of the housing, the display device displaying a physical quantity of the detection target detected by the detection unit;
a first substrate having a controller mounted thereon, the controller being electrically connected to the display and causing the display to display the physical quantity of the detection target detected by the detection unit;
an indicator light provided on the first surface and outputting a comparison result between the physical quantity detected by the detection unit and a threshold value;
an adjustment button provided on the first surface for adjusting the threshold value;
The indicator light, the display, and the adjustment button are arranged in a longitudinal direction of the first surface,
The OLED layer of the display is formed offset toward the indicator light along a longitudinal direction of the transparent member,
a transparent electrode extending from the OLED layer is formed on an end of the transparent member on the side of the adjustment button in the longitudinal direction;
The present invention provides a sensor unit, characterized in that the display has a non-display area on the upper surface of the display that does not display information and a display area that displays information, the non-display area being covered and the display area being exposed.

The present invention provides a signal cable connection structure that ensures a sufficient display area for the display in a photoelectric switch.

A perspective view showing a photoelectric switch FIG. 1 is a perspective view showing a plurality of photoelectric switches connected together; Explosion diagram showing a photoelectric switch A perspective view showing a photoelectric switch FIG. 2 is a perspective view showing the positional relationship between a cover member, a display unit, and a shield member; Diagram explaining the upper case, etc. Diagram explaining the relationship between the display and the signal cable Diagram explaining the position of the slits Diagram explaining the position of the slits FIG. 1 shows an integrated signal cable and shielding member. Diagram explaining the relationship between the display and the signal cable Cross-section of a photoelectric switch Enlarged cross-section of a photoelectric switch

One embodiment of the present invention is described below. The individual embodiments described below will be useful for understanding various concepts, such as higher-level, middle-level, and lower-level concepts, of the present invention. Furthermore, the technical scope of the present invention is determined by the claims, and is not limited by the individual embodiments described below.

1 is a perspective view of a photoelectric switch. The photoelectric switch 1 has a substantially rectangular housing. Here, the z-axis corresponds to the longitudinal direction. The x-axis corresponds to the lateral direction. The y-axis corresponds to the height direction. The housing has approximately six outer surfaces. The six outer surfaces include the top, bottom, front, back, left side, and right side. In FIG. 1, the top, front, and right side are visible. The housing has a lower case 2 and an upper case 3. By fitting the lower case 2 and the upper case 3 together, an internal space is formed in which a control board and the like are housed. A part of the upper case 3 forms the upper surface. The upper surface is provided with a display 5, a mode button 7, an active receiver button 8, an adjustment button 9, a slide switch 10, a set button 11, an indicator light 24, a clamp module 14, and the like. The display 5 is a dot matrix display such as an OLED, and displays a threshold value, an amount of received light, and the like. The display 5 is clamped and fixed between the outer surface of the upper case 3 and the cover member 4. The display 5 is provided offset toward the front side from the center of the top surface. The adjustment button 9 is a button for increasing or decreasing the threshold value or operating the menu. The menu is a menu that is displayed on the display 5 and has various setting items for setting the operation of the photoelectric switch 1. The mode button 7 is a button for switching the operation mode related to the amount of light emitted, etc. The active receiver button 8 is a special button for emitting light from the photoelectric switch 1 to the outside through the receiving optical fiber. When the photoelectric switch 1 detects the pressing of the active receiver button 8, the receiving optical fiber is also used as the projecting optical fiber, and while receiving light incident from the outside, it projects light toward the outside. This light is not light for detecting the workpiece, but light for assisting the user in adjusting the optical axis. The light-emitting element that outputs the assist light may be disposed, for example, in the center of the light-receiving element. In this case, the light-receiving surface of the light-receiving element is larger than the light-emitting surface of the light-emitting element. The slide switch 10 is a switch for selecting a set of setting parameters from among a plurality of sets. The set button 11 is a button for starting automatic setting of the threshold value. When the photoelectric switch 1 detects that the set button 11 has been pressed, it determines a threshold value according to the amount of light received. The indicator light 24 turns on or off, for example, when a workpiece is detected. The clamp module 14 is a module that clamps and holds the light emitting fiber and the light receiving fiber. The front surface of the housing is provided with a cylindrical hole 12 into which the light emitting fiber is inserted and a cylindrical hole 13 into which the light receiving fiber is inserted. The output cable is attached to the rear surface of the housing. The cable bush 15 is a bush for holding the output cable.

The right side of the housing is provided with a connector 16a and connecting parts 17a and 17b. FIG. 2(A) shows that a plurality of photoelectric switches 1 are connected to each other by the connector 16a and connecting parts 17a and 17b, respectively, and fixed to a DIN rail 18. DIN is an abbreviation for the German Institute for Standardization. The incident end of the light-emitting fiber 22 is inserted into the hole 12, and the emission end of the light-receiving fiber 23 is inserted into the hole 13. FIG. 2(A) also shows an openable and closable upper cover 19 that covers the upper surface of the housing. Note that, as shown in FIG. 2(B), if the upper cover 19 is translucent, the upper surface of the upper cover 19 does not need to have a hole. This is because, if the upper cover 19 is translucent, the user can check the display content of the display unit 5 even when the upper cover 19 is closed. If the upper cover 19 is not translucent, a hole or a window may be provided on the upper surface of the upper cover 19, as shown in FIG. 2(A). The upper cover 19 functions as a dust cover. As shown in Figures 2(A) and (B), multiple photoelectric switches 1 can be connected together horizontally, so they are also called linked sensors.

Figure 3 is an exploded view of the photoelectric switch 1. A decorative member 20 may be provided on the rear end side of the upper cover 19. A pivot pin 19a is provided on the rear end side of the upper cover 19. The pivot pin 19a fits into a retaining hole 19b provided on the rear end side of the upper case 3. This allows the upper cover 19 to be pivotally connected to the upper case 3. The upper cover 19 may be made of a transparent material so that the user can check the information displayed on the display 5 even when the upper cover 19 is closed. A spine member 36 for supporting the display 5 is provided near the center of the upper case 3. Four fringes 47 are provided on the left and right sides of the spine member 36. The four fringes 47 are protrusions that protrude upward from the upper case 3 and position the display 5 in the short side direction (x direction). The four fringes 47 fit into recesses in the cover member 4. In addition, two claws 48 are provided on the left and right sides of the spine member 36. The claw portion 48 fits into a recess provided on the inside of the central leg of the cover member, and fixes the cover member 4 to the upper case 3. The recess may be a groove or a through hole. An opening 25 is provided on the rear end side of the display mounting portion centered on the spine member 36. The opening 25 is a through hole or a notch for passing a signal cable from the outer surface to the inner surface of the upper case 3. The signal cable includes a power line that supplies power to the display 5 and a control line that supplies a control signal. The signal cable is connected to the control board 30. Here, the control board 30 may be a single board. If two boards are provided in the x-axis direction, the length of the photoelectric switch 1 in the x-axis direction will be long. Therefore, in this embodiment, only one control board 30 is provided in the x-axis direction. The control board 30 is equipped with a controller 6 such as a CPU (Central Processing Unit). The controller 6 displays the threshold value and the amount of received light on the display 5. The control board 30 is equipped with switches corresponding to the adjustment button 9, the mode button 7, the active receiver button 8, the slide switch 10, and the set button 11. These buttons may be made of resin such as POM (polyacetal). The upper cover 19, the cover member 4, and the housing may basically be made of polycarbonate. An LED (light-emitting diode) that supplies light to the light diffusion member of the indicator lamp 24 is also mounted on the control board 30. The control board 30 is provided with a connector 16a for communicating with another adjacent photoelectric switch 1 and for receiving power. An element holder 26 is provided on the front side of the control board 30, and a light-emitting element 32 and a light-receiving element 33 are attached thereto. The element holder 26 has a hole for the light-emitting fiber 22 inserted from the hole 12 and a hole for the light-receiving fiber 23 inserted from the hole 13. A clamp module 14 is disposed on the front side of the element holder 26 and holds the light-emitting fiber 22 and the light-receiving fiber 23. A fixture 28 for fixing to the DIN rail 18 and a metal cover 29 are attached to the bottom surface of the lower case 2. The metal cover 29 may serve as a heat sink and an electromagnetic shield.

Figure 4 (A) is a perspective view of the photoelectric switch 1 with the cover member 4 fixed to the upper case 3. Figure 4 (B) is a perspective view of the photoelectric switch 1 with the cover member 4 not fixed to the upper case 3. Here, various buttons and indicators 5 are fixed to the upper case 3, and the control board 30 is also fixed to the upper case 3. A signal cable 51 electrically connecting the indicator 5 and the control board 30 passes through the opening 25 and enters the inside of the housing, and is connected to the connector of the control board 30. A connector 16b is provided on the left side of the control board 30. The connector 16b of the photoelectric switch 1 is a female connector, and is electrically connected by fitting with the male connector 16a of another photoelectric switch 1 located to the left of the photoelectric switch 1.

As can be seen from FIG. 4(A) and other figures, the height of the active receiver button 8 is lower than the height of the mode button 7 and adjustment button 9. This is to prevent accidental operation of the active receiver button 8.

Figure 5 is a perspective view for explaining the cover member 4 in detail. The cover member 4 has two front legs 42, two central legs 43, and two rear legs 44. A window portion 40 is provided on the upper surface of the cover member 4. The user can see the display surface of the display unit 5 through the window portion 40. The window portion 40 is surrounded by four frames. The left frame 41a and the right frame 41b are thinner than the front frame 41d and the rear frame 41c. This is to ensure the display area in the short direction of the photoelectric switch 1. The rear frame 41c has a larger area than the other frames. This is because the rear frame 41c protects the IC that controls the display unit 5. Character information, etc. may be printed on the rear frame 41c. In addition, since the rear frame 41c has a certain area, even if the user presses the adjustment button 9 with his finger, the display information of the display unit 5 is unlikely to be hidden by the finger. In other words, the rear frame 41 can sufficiently separate the distance between the display unit 5 and the button. In addition, since the area of the front frame 41 is small, the indicator light 24 and the display unit 5 can be placed close to each other. This allows the information transmission mechanism that attracts the user's attention to be concentrated in one place. A total of four notches 46 are provided on the right and left sides of the cover member 4. The four notches 46 fit into four fringes 47 provided on the upper case 3 to position and fix the cover member 4 relative to the upper case 3. Recesses 45 are provided on the inner surfaces of the two center legs 43. The recesses 45 fit into claws 48 provided on the right and left sides of the upper case 3. A shield member 50 may be used to protect the front, bottom, left and right sides of the display 5. The shield member 50 has a front wall 50d that protects the front of the display 5, a bottom 50a that protects the bottom of the display 5, a right wall 50b that protects the right side of the display 5, and a left wall 50c that protects the left side of the display 5. The display 5 is sandwiched between the spine member 36 and the cover member 4 while covered by the shield member 50. The shielding member 50 may be formed from an FPC (flexible printed circuit board).

Figure 6 (A) is a plan view showing the top surface of the photoelectric switch 1. As shown in Figure 6 (A), no switches or buttons are provided in the short direction of the display 5. This allows the dimension of the display 5 in the short direction to be sufficiently large. The rear frame of the cover member 4 has an area large enough to allow characters, etc. to be printed.

Figure 6 (B) shows the left side of the upper case 3. Figure 6 (C) shows the left side of the upper case 3 with the control board 30 attached. The terminal 52 of the signal cable 51 extending from the display 5 is connected to and fixed in place in the connector 16c mounted on the control board 30. The signal cable 51 enters from the outside of the housing to the inside and is connected to the control board 30, so it is made of a thin and flexible FPC cable or the like.

Figure 6 (D) shows the photoelectric switch 1 with the lower case 2 attached. Fixing holes 63a and 63b are provided on the left side of the lower case 2. The fixing holes 63a and 63b of the photoelectric switch 1 receive the connecting parts 17a and 17b of another photoelectric switch 1 located adjacent to the left. Note that a hole is provided on the left side of the lower case 2 through which the connector 16b is exposed, but in Figure 6 (D) the hole is protected by a lid 64.

<Signal cable layout for display unit>
FIG. 7A shows the right side of the display 5. The display 5 is formed by stacking a transparent member 70, an OLED layer 71, and a transparent base material 72 in the height direction. The transparent member 70 and the transparent base material 72 are made of a transparent substrate (second substrate) containing glass, resin, or the like. The transparent electrodes extending from the long side of the OLED layer 71 and the transparent electrodes extending from the short side are formed on the bottom surface of the transparent member 70 and are electrically connected to the driving IC 54. The driving IC 54 is an integrated circuit that drives the display 5. The driving IC 54 is fixed to the bottom surface of the transparent member 70 by adhesive 73. A signal cable 51 extending from the control board 30 is electrically connected to the terminal of the driving IC 54. In this way, the signal cable 51 is connected to the end of the longitudinal direction of the display 5, that is, to the terminal (connection portion 70a) provided on the short side of the display 5. This makes it easier to ensure the display area in the short direction of the display 5. At the manufacturing and inspection site of the workpiece, a plurality of photoelectric switches 1 are connected and used. Therefore, the length of the short side of the photoelectric switch 1 is, for example, 5 mm or more and 14 mm or less. If the driving IC 54 and the signal cable 51 are attached to the short side of the display 5, the display area of the display 5 will be narrowed. In other words, it will be difficult to read the characters displayed on the display 5. Therefore, it is preferable that the driving IC 54 and the signal cable 51 are not attached to the end (long side) of the short side of the display 5.

Figure 7 (B) shows that a driver IC 54 is provided midway along the signal cable 51. This will help to shorten the longitudinal length of the transparent member 70. The transparent electrodes extending from the long sides of the OLED layer 71 are connected to the signal cable 51 as terminals (connection parts 70a) provided on the short sides of the display 5.

Figure 7 (C) shows that the backbone member 36 of the upper case 3 is used as the base material instead of the transparent base material 72. This helps to make the display 5 thinner. In other words, it helps to reduce the height of the display 5. The backbone member 36 has an opening 25, and the signal cable 51 passes through the opening 25 to enter the inside of the housing. The driving IC 54 is disposed midway along the signal cable 51 and is located inside the housing. The transparent electrode extending from the long side of the OLED layer 71 and provided on the transparent member 70 is connected to the signal cable 51 as a terminal (connection portion 70a) provided on the short side of the display 5.

In this way, the display 5 has an OLED layer 71 that functions as a display layer, and a transparent member 70. The transparent electrode functions as a signal line that runs from the OLED layer 71 to the signal cable 51. The transparent electrode is provided near the interface between the OLED layer 71 and the transparent member 70. The cover member 4 covers the side surface near the interface between the OLED layer 71 and the transparent member 70. Since this interface is easily damaged, the cover member 4 protects the interface.

<Cable Passage Arrangement>
FIG. 8(A) shows a schematic cross-sectional view of the upper case 3. FIG. 8(B) to FIG. 8(E) show perspective views of the display mounting portion. The upper case 3 includes a first upper surface 38 on which the set button 11 is arranged, a second upper surface (front wall 37), a third upper surface (backbone member 36), a fourth upper surface (rear wall 35), and a sixth upper surface 34 on which the adjustment buttons 9 and the like are arranged. The first upper surface 38 and the sixth upper surface 34 may be called the upper stage, and the backbone member 36 may be called the lower stage. In this way, the upper surface of the upper case 3 may have a step. The backbone member 36 may be called a mounting portion. The mounting portion may be solid from the viewpoint of improving rigidity. As shown in FIG. 8(A), the second upper surface (front wall 37), the third upper surface (backbone member 36), and the fourth upper surface (rear wall 35) form a recess in a cross section along the longitudinal direction of the housing. The display 5 is pressed against the wall surface (front wall 37) that is closer to the second surface out of the two wall surfaces that form the recess. According to FIG. 8(A) and FIG. 8(B), the opening 25 is a slit-shaped hole provided on the rear end side of the spine member 36. This suggests that the opening 25 may be provided on the front end side of the spine member 36. According to FIG. 8(C), the opening 25 is provided on the lower side of the rear wall 35. This suggests that the opening 25 may be provided on the lower side of the front wall 37. The opening 25 may be provided at the connection part between the spine member 36 and the rear wall 35 (front wall 37). That is, a slit may be formed across the spine member 36 and the rear wall 35 (front wall 37). FIG. 8(D) shows that the opening 25 is provided in the center of the spine member 36. Here, the area of the opening 25 is basically smaller than the bottom area of the display 5. This is because the bottom surface of the display 5 is supported by the spine member 36. However, it is sufficient that the bottom surface of the display 5 is supported by either two long frames extending in the longitudinal direction of the spine member 36 or two short frames extending in the lateral direction of the spine member 36. FIG. 8(E) shows that a notched opening 25 is provided on the right side of the spine member 36. This suggests that the notched opening 25 may be provided on the left side of the spine member 36. If the signal cable 51 is a highly flexible and bendable cable such as an FPC cable, the degree of freedom in arranging the opening 25 will increase. Note that the case of FIG. 8(E) is a case in which the signal cable 51 is mainly connected to the long side of the display 5. However, if the signal cable 51 is an FPC cable, it may be possible to pass the signal cable 51 extending from the short side of the display 5 through the notched opening 25 shown in FIG. 8(E).

Figure 9 (A) shows the opening 25 provided at the rear end of the spine member 36. As shown in Figure 9 (A), the housing of the photoelectric switch 1 is long and narrow. Also, looking at the spine member 36, it can be seen that the display mounting portion is present up to the edge of the housing. This helps to enlarge the display area of the display 5. Also, the fact that the opening 25 is provided on the rear end side of the spine member 36 also helps to enlarge the display area of the display 5. Figure 9 (B) shows the signal cable 51 bent in order to pass through the opening 25. In this way, the signal cable 51 extends from the outside to the inside of the upper case 3 through the opening 25.

<Integrated shielding of signal cables>
FIG. 10 shows a signal cable 51 made of an FPC 60. Here, a display module including a display 5 and a driving IC 54 is also shown together with the signal cable 51. The signal cable 51 is integrated by a shielding member 50 and an FPC 60. The shielding member 50 has a metal layer such as copper and a base film layer. The right wall 50b is formed by folding the FPC 60 at a right angle at the crease 56c. The left wall 50c is formed by folding the FPC 60 at a right angle at the crease 56d. The front wall 50d is formed by folding the FPC 60 at a right angle at the crease 56e. In order to make it easier to fold the FPC 60, a plurality of holes 55 may be provided in the metal layer along the creases 56c, 56d, and 56e. The metal layer is connected to the ground line of the signal cable 51. This allows the shielding member 50 to protect the OLED (display 5) from electrical noise.

Furthermore, by folding the FPC 60 at a right angle along the crease 56a, the shielding member 50 covers the bottom surface of the display 5. The U-shaped folded portion of the signal cable 51 shown in FIG. 9(B) is formed by overlapping the signal wiring portion 53a and the shield wiring portion 53b of the FPC 60. In other words, by folding the FPC 60 at a right angle along the crease 56a, the signal wiring portion 53a and the shield wiring portion 53b overlap. Furthermore, when inserted into the opening 25, the overlapping portion of the signal wiring portion 53a and the shield wiring portion 53b is folded in a U shape. Furthermore, by folding the FPC 60 at a right angle at the crease 56b, the mounting surface of the terminal 52 becomes parallel to the control board 30.

11(A) to 11(E) show the positional relationship between the display 5 and the signal cable 51. FIG. 11(A) is a plan view of the display 5 connected to the signal cable 51. FIG. 11(B) is a view showing the left side of the display 5. The signal cable 51 extending from the rear end side of the display 5 is bent into a U shape at the overlapping portion 53 formed by overlapping the signal wiring portion 53a and the shield wiring portion 53b. Furthermore, by bending the signal cable 51 at a right angle at the crease 56b, the mounting surface of the terminal 52 becomes parallel to the control board 30. FIG. 11(C) to 11(E) are perspective views of the display 5. The mounting surface of the terminal 52 becomes parallel to the control board 30, but is perpendicular to the bottom surface of the display 5.

The terminal 52 may be composed of, for example, eight pins. The VCC pin is a pin that supplies power to the driving IC 54. The VSS pin is a pin that is connected to ground (provides a ground potential). The RES pin is a pin that supplies a reset signal to the driving IC 54 for starting or restarting the driving IC 54. The SCLK pin is a pin that supplies a clock for serial communication. The SDA pin is a pin for transmitting data for serial communication. The IREF pin is a pin for adjusting the current flowing through the OLED layer 71. The VCOMH pin is a pin for connecting an external capacitor to the driving IC 54 in order to stabilize the internal power supply of the driving IC 54. The VDD pin is a pin that supplies a voltage for the logic operation of the driving IC 54.

The shielding member 50 may be a shielding sheet made of a separate material from the signal cable 51.

<Shield>
FIG. 12(A) is an A-A cross-sectional view obtained by cutting the photoelectric switch 1 along the A-A cutting line in FIG. 6(D). FIG. 12(B) is a B-B cross-sectional view obtained by cutting the photoelectric switch 1 along the B-B cutting line in FIG. 6(D). FIG. 13 is an enlarged view of a part of FIG. 12(A). As shown in FIG. 12(A) and FIG. 13, the claws 48 of the upper case 3 are fitted into the recesses 45 provided in the left and right central legs 43 of the cover member 4. As shown in FIG. 12(A), FIG. 12(B), and FIG. 13, the heights of the right wall 50b and the left wall 50c of the shield member 50 are such that they cover the OLED layer 71 and the transparent base material 72 of the display 5, respectively, and cover at least a part of the transparent member 70. The transparent member 70 and the transparent base material 72 are made of glass or the like. Glass is more easily broken than resin. Therefore, the shield member 50 protects the transparent member 70 and the transparent base material 72 from impacts and the like. The OLED layer 71 is further protected from electrical noise by the shielding member 50. The bottom surface of the display 5 is covered by a bottom portion 50a of the shielding member 50. The backbone member 36 makes it difficult for heat generated from the control board 30 to be transmitted to the display 5.

As shown in FIG. 12(B), the tips of the left and right front legs 42 of the cover member 4 are clamped between the lower case 2 and the upper case 3. This allows the cover member 4 to be firmly fixed to the housing.

<Summary>
As described with reference to FIG. 1 and the like, the photoelectric switch 1 has a housing having a substantially rectangular parallelepiped shape. In other words, the housing is long and narrow. The display 5 is an example of a display unit attached to the first surface of the housing. Conventionally, the display was housed inside the housing of the photoelectric switch, so there was a distance between the outer surface of the housing and the display, making it difficult to see the displayed information. In this embodiment, the display 5 is attached to the outer surface of the housing, so the distance from the outer edge of the photoelectric switch 1 to the display 5 is shortened, making it easier to see the displayed information of the display 5. The light-emitting element 32 and the hole 12 are an example of a light-projecting unit provided near the second surface located next to the first surface. The light-receiving element 33 and the hole 13 are an example of a light-receiving unit provided near the second surface located next to the first surface. The adjustment button 9 and the like are an example of a receiving unit provided on the first surface or the display unit and receiving a user operation. The controller 6 is an example of a display control unit that causes the display unit to display the threshold value adjusted through the receiving unit and a signal value indicating the amount of light received by the light-receiving unit. The control board 30 is an example of a control board (first board) that is housed inside the housing and on which the display control unit is mounted or connected. The signal cable 51 is an example of a signal cable that connects the control board 30 and the display 5. As shown in Figs. 6(A) to 6(C), the display 5 has a connection portion that is connected to the signal cable 51. The connection portion of the display 5 is disposed between the display area and the signal cable 51 in the longitudinal direction of the housing. As shown in Figs. 7(A) to 7(C) and 10, the display 5 may have two short sides and two long sides, and the signal cable 51 may be connected to one of the two short sides. This provides a connection structure for the signal cable 51 that can ensure a sufficient display area for the display 5 in the photoelectric switch 1.

The display unit may have a dot matrix display and a drive circuit for driving the dot matrix display. The display 5 is an example of a dot matrix display. The drive IC 54 is an example of a drive circuit. As shown in FIG. 7(A) and other figures, the drive IC 54 is provided at the end of the display 5 in the longitudinal direction, and a signal cable 51 is connected to the drive IC 54. In other words, the drive IC 54 may be provided between the display 5 and the connection unit in the longitudinal direction of the housing. The display 5 and the drive IC 54 may be disposed on the same member. According to FIG. 7(A), the OLED layer 71 and the drive IC 54 of the display 5 are disposed on a transparent member 70.

As shown in FIG. 11(B) and FIG. 11(C), the signal cable 51 may have a first portion that connects the display 5 and the driving IC 54, and a second portion that connects the driving IC 54 and the control board 30. As shown in FIG. 10, the signal cable 51 may be an FPC cable. This makes it easier to connect the display 5 arranged outside the housing to the control board 30 arranged inside the housing.

The housing may have an upper case 3 and a lower case 2. In this case, the first surface is the top surface of the upper case 3.

According to the present invention, the opening 25 is provided on the outer surface of the housing, particularly on the upper surface. The opening 25 allows the signal cable 51 to be arranged from the inside to the outside of the housing, and allows the display 5 to be attached to the outer surface of the housing. That is, the signal cable 51 is connected to the control board 30 through the opening 25. Since the display 5 is provided on the outer surface of the housing, the user is unlikely to get the impression that the display 5 is recessed. Therefore, the display 5 is easy for the user to see. The short side of the display 5 to which the signal cable 51 is connected may be the short side farther from the second surface (front surface of the display 5) of the two short sides of the display 5. In this case, the opening 25 may be provided on the rear end side of the backbone member 36, etc. The short side of the display 5 to which the signal cable 51 is connected may be the short side closer to the second surface (front surface) of the two short sides of the display 5. In this case, the opening 25 may be provided on the front end side of the backbone member 36, etc. The spine member 36 of the upper case 3 is supported by the control board 30. This helps to improve the rigidity of the housing. Furthermore, by making the thickness of the spine member 36 thicker than the thickness of other parts of the upper case 3, the structure of the upper case 3 itself is improved. In particular, by increasing the rigidity of the spine member 36, it becomes easier to protect the display 5.

As described with reference to Figures 8(A) to 8(E), the first surface (top surface) of the upper case 3 has an opening 25. The opening 25 functions as a hole-like or notched passage for passing the signal cable 51 from the outside to the inside of the housing. As shown in Figure 8(B) and other figures, the opening 25 may be a slit provided along the short direction (x-axis direction) of the first surface. As shown in Figure 8(E) and other figures, the opening 25 may be a slit provided along the long direction (z-axis direction) of the first surface. As shown in Figure 7(C), the driving IC 54 may be housed inside the housing. This reduces the size of the mounting portion for the display 5. As shown in Figure 1 and other figures, the long direction of the display 5 and the long direction of the first surface are parallel.

As shown in FIG. 5 and the like, the cover member 4 is used as a holding member for holding the display 5 provided on the outer surface of the housing. This allows the display 5 to be arranged on the outer surface of the housing, making it easier for the user to see the information displayed on the display 5. By arranging the cover member 4 on the outside of the housing in this way, the display area of the display 5 can be enlarged. However, if the display 5 is arranged on the outer surface of the housing, the display 5 is more susceptible to external impacts. Therefore, the cover member 4 has a role of protecting the display 5. Furthermore, as shown in FIG. 5 and FIG. 10, the shield member 50 is an example of a shield member provided on at least a part of the side surface of the display 5. As shown in FIG. 13 and the like, the cover member 4 is an example of a cover member that sandwiches the shield member 50 between the side surface of the display 5 and the cover member 4, and covers at least a part of the side surface of the display 5. In this way, the shield member 50 also has a role of protecting the display 5 from impacts.

As shown in FIG. 5, the cover member 4 may have a window portion 40 that exposes the display area of the display unit 5. The cover member 4 may be configured to cover the non-display area of the display unit 5. The non-display area is a portion of the upper surface of the display unit 5 that does not display information.

Of the four frames located around the window 40 in the cover member 4, the thickness of one frame located at the longitudinal end of the window 40 (e.g., right frame 41b, left frame 41a) is thicker than the two frames located at both ends of the window 40 in the lateral direction (e.g., front frame 41d, rear frame 41c). This makes it easier to ensure the display area of the display 5 in the lateral direction. The cover member 4 may be configured to engage with a protruding portion protruding from the first surface. For example, a protruding portion (fringe 47) protruding from the top surface of the upper case 3 may engage with the notch 46 of the cover member 4.

The shielding member 50 may be electrically connected to the ground wire of the signal cable 51. This allows the shielding member 50 to reduce the effect of electrical noise on the display 5.

As shown in FIG. 13, the length of the short side of the first surface of the upper case 3 is approximately equal to the sum of the length of the short side of the display 5, the thickness of the side surfaces (central leg 43) located at both ends of the short side of the cover member 4, and the thickness of the shield member 50 (right wall 50b, left wall 50c). This makes it possible to make the short side length of the display 5 closer to the short side length of the top surface of the photoelectric switch 1 while protecting the display 5 with the shield member 50. In other words, it becomes easier to increase the size of the characters that can be displayed on the display 5.

As shown in FIG. 10, the signal cable 51 and the shielding member 50 may be an integrated FPC cable. This allows the number of parts to be reduced. It also makes it easier to integrate the ground wire to the shielding member 50 with the signal cable 51.

As shown in FIG. 10 and FIG. 11(B), the FPC cable may be bent at least at one location. Furthermore, a portion of the shielding member 50 and a portion of the signal cable 51 may overlap.

The shield member 50 may have a first region (bottom 50a) that covers the bottom surface of the display 5, a second region (right wall 50b) that protects the first side surface of the display 5, a third region (left wall 50c) that protects the second side surface of the display 5, and a fourth region (front wall 50d) that protects the third side surface of the display 5. As shown in FIG. 10, the second region, the third region, and the fourth region may be connected to the first region.

The top cover 19 is an example of an openable lid that covers the reception section and the display 5 covered by the cover member 4. This makes it less likely that oil droplets generated in the factory will adhere to the adjustment buttons 9 and the display 5. It also makes it less likely that the adjustment buttons 9 and the display 5 will be damaged. The cover member 4 is a cover that covers part of the display 5, and is provided on the outside of the first surface of the housing. As shown in Figures 6(B) and 9(B), the height of the top surface of the cover member 4 in the height direction of the housing may be approximately the same as the height of the surface of the first surface on which the reception section is provided.

As shown in FIG. 1 and other figures, the opening 25 may be covered by a cover member 4 or a display 5. This makes it difficult for foreign matter to enter the inside of the housing through the opening 25.

Characters may be written on the surface of one of the frames (e.g., rear frame 41c) located at the longitudinal end of window portion 40. For example, when a transmissive fiber is used, there are operation modes such as D-ON (dark on) in which indicator light 24 turns on when a workpiece is detected, and L-ON (light on) in which indicator light 24 turns off when a workpiece is detected. In this case, display 5 may display a mark (e.g., an arrow mark) that indicates either "L-ON" or "D-ON" printed on rear frame 41c. Since the rear end of display 5 and rear frame 41c are adjacent, display 5 may display information linked to the information displayed on rear frame 41c.

As shown in FIG. 7(A), the display 5 may have a transparent member (transparent member 70), an OLED (OLED layer 71) provided on the underside of the transparent member, and a substrate (transparent substrate 72, backbone member 36) provided on the underside of the OLED. The cover member 4 is provided to protect at least the OLED layer 71. This reduces damage to the OLED layer 71 and the effects of electrical noise.

As shown in FIG. 13, the thickness of the cover member 4 is thinner than the thickness of the housing (upper case 3 and lower case 2). This makes it possible to make the short-side length of the display 5 as long as possible. It also makes it possible to increase the display area of the display 5, making it possible to increase the size of the characters displayed.

In the above embodiment, the photoelectric switch 1 is used as an example of the sensor unit. However, the sensor unit may be a sensor unit that detects other physical quantities, such as a pressure sensor. The light receiving element 33 is an example of a detection unit, but may also be a detection element that detects a physical quantity (e.g., amount of received light or pressure) detected from a detection target and outputs a detection signal according to the physical quantity. The display 5 is an example of a display unit that displays the physical quantity detected by the detection unit. The indicator light 24 and the output cable to the outside are examples of an output unit that outputs a comparison result between the physical quantity detected by the detection unit and the threshold value. The adjustment button 9 is an example of a reception unit or operation unit that receives an adjustment operation of the threshold value. The adjustment button 9 is also an example of a threshold adjustment unit that adjusts the threshold value. The controller 6 is an example of a display control unit that displays the threshold value adjusted through the reception unit and a signal value indicating the physical quantity detected by the detection unit in the display area of the display unit. The connection unit of the display unit 5 is disposed between the adjustment button 9 and the display area (OLED layer) of the display unit 5.

As shown in FIG. 3, the lower case 2 is a lower case with an open surface and a concave cross section. The upper case 3 is configured to cover the upper surface of the lower case 2. The upper case 3 and the lower case 2 form the housing of the photoelectric switch 1. The control board 30 is an example of a first board, and is housed in the lower case 2 so as to face a third surface located adjacent to the first surface and the second surface. Here, the first surface is the upper surface of the upper case 3. The third surface is, for example, the connecting portions 17a and 17b. More precisely, the third surface is one of the inner surfaces that form the lower case 2.

The present invention relates to, for example,
A detection unit for detecting a physical quantity from a detection target;
a dot matrix display for displaying a physical quantity of the detection target detected by the detection unit;
an adjustment button for adjusting a threshold value for the physical quantity ;
a controller that displays the threshold value adjusted via the adjustment button and the physical quantity of the detection target detected by the detection unit in a display area of the dot matrix display ;
an indicator light that outputs a comparison result between the physical quantity detected by the detection unit and a threshold value;
a first substrate on which the LED of the indicator light is mounted ,
the indicator lamp, the dot matrix display , and the adjustment button are arranged in the following order along a longitudinal direction of the dot matrix display : the indicator lamp, the dot matrix display, and the adjustment button ;
a display area of the dot matrix display is offset toward the indicator lamp along a longitudinal direction;
The present invention provides a sensor unit characterized in that the dot matrix display has a terminal for a signal line for display provided on the adjustment button side in the longitudinal direction.

Claims (10)

A detection unit for detecting a physical quantity from a detection target;
A housing having a substantially rectangular parallelepiped shape;
a display device that includes an OLED layer functioning as a display layer and a rectangular transparent member and is provided on a first surface of the housing, the display device displaying a physical quantity of the detection target detected by the detection unit;
a first substrate having a controller mounted thereon, the controller being electrically connected to the display and causing the display to display the physical quantity of the detection target detected by the detection unit;
an indicator light provided on the first surface and outputting a comparison result between the physical quantity detected by the detection unit and a threshold value;
an adjustment button provided on the first surface for adjusting the threshold value;
The indicator lamp, the display, and the adjustment button are arranged in a longitudinal direction of the first surface,
The OLED layer of the display is formed offset toward the indicator light along a longitudinal direction of the transparent member,
a transparent electrode extending from the OLED layer is formed on an end of the transparent member on the side of the adjustment button in the longitudinal direction;
The sensor unit is characterized in that the display has a non-display area on an upper surface of the display that does not display information and a display area that displays information, the non-display area being covered and the display area being exposed. the sensor unit further includes a cover member having a window portion through which the display area is exposed and which holds the display on an outer surface of the housing;
The sensor unit according to claim 1 , wherein the non-display area of the display is covered by the cover member. The display has a substrate laminated on a lower surface side of the OLED layer,
The sensor unit according to claim 1 , further comprising a shielding member that covers the OLED layer and the base material, covers at least a portion of the transparent member, and protects the display. The display has a substrate laminated on a lower surface side of the OLED layer,
The sensor unit further includes a shielding member that covers the OLED layer and the base material, covers at least a portion of the transparent member, and protects the display.
a cover member having a window portion exposing the display area and provided to protect at least the OLED layer;
The sensor unit according to claim 1 , wherein the cover member sandwiches a shield member between the cover member and the display. a hole for a light emitting fiber and a hole for a light receiving fiber are formed in a second surface of the housing adjacent to the first surface;
the sensor unit includes a clamp module that clamps and holds a light emitting fiber to be inserted into the hole for the light emitting fiber and a light receiving fiber to be inserted into the hole for the light receiving fiber;
The sensor unit according to claim 1 , wherein the indicator light is disposed between the indicator and the clamp module. the sensor unit further includes a set button provided on the first surface for starting automatic setting of the threshold value;
The sensor unit according to claim 1 , wherein the set button is disposed between the display and the indicator light. The indicator light has a light diffusing member,
The sensor unit according to claim 1 , wherein an LED that supplies light to the light diffusing member is mounted on the first substrate. a light receiving element for detecting an amount of light received from a detection target;
A housing having a substantially rectangular parallelepiped shape;
a display device in which an OLED layer functioning as a display layer and a rectangular transparent member are laminated and provided on a first surface of the housing, the display device displaying an amount of light received by the light receiving element;
a first substrate having a controller mounted thereon, the first substrate being electrically connected to the display and causing the display to display an amount of light received by the light receiving element of the detection target;
an indicator light provided on the first surface and outputting a comparison result between the amount of received light detected by the light receiving element and a threshold value;
an adjustment button provided on the first surface for adjusting the threshold value;
The indicator lamp, the display, and the adjustment button are arranged in a longitudinal direction of the first surface,
The OLED layer of the display is formed offset toward the indicator light along a longitudinal direction of the transparent member,
a transparent electrode extending from the OLED layer is formed on an end of the transparent member on the adjustment button side in the longitudinal direction;
A photoelectric switch characterized in that the display has a non-display area on an upper surface of the display that does not display information and a display area that displays information, the non-display area being covered and the display area being exposed. a hole for a light emitting fiber and a hole for a light receiving fiber are formed in a second surface of the housing located adjacent to the first surface;
The photoelectric switch further includes a clamp module that clamps and holds a light emitting fiber inserted into the hole for the light emitting fiber and a light receiving fiber inserted into the hole for the light receiving fiber,
The photoelectric switch of claim 8 , wherein the indicator light is disposed between the indicator and the clamp module. the photoelectric switch further includes a set button provided on the first surface for starting automatic setting of the threshold value;
The photoelectric switch according to claim 8 or 9, wherein the set button is disposed between the indicator and the indicator light.

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