JP7547804B2 - Protective cover for alarm device and alarm device - Google Patents

Description

The present invention relates to a protective cover for an alarm device and an alarm device.

Traditionally, in thermal power plants, coal fuel is transported from a coal silo to a boiler by a belt conveyor and supplied to the boiler. However, due to the risk of coal catching fire due to frictional heat generated by the belt conveyor, multiple fire alarms are distributed around the belt conveyor to keep an eye on fires. The type of fire alarm used is one that issues an alarm sound or signal when an operator presses a push button. Generally, this type of alarm has a cover placed on the front side of the push button to protect it from accidental activation, and the push button can be pressed by pushing or breaking the cover (see Patent Documents 1 to 3, etc.).

JP 2011-054111 A JP 2016-200974 A Utility Model Registration No. 3166560

Incidentally, in thermal power plants such as those described above, when coal is loaded from a coal silo onto the conveyor belt, or while it is being transported by the conveyor belt, coal falls from the conveyor belt onto the floor. In this case, the fallen coal may bounce off the floor and hit the cover protecting the fire alarm push button, causing the cover to come off or break, resulting in a false alarm, such as pressing the push button. In other words, conventional alarm devices such as fire alarms may malfunction when hit by flying objects such as the fallen coal described above, and in this regard there is room for improvement.

The present invention was made in consideration of the above circumstances, and aims to provide a protective cover for an alarm device and an alarm device that can prevent malfunctions caused by the push button of the alarm device being pressed unintentionally.

The protective cover for an alarm device of the present invention is a protective cover provided for an alarm device that includes a device body, a push button provided on the device body that activates transmission of an alarm signal when pressed, and a push button cover arranged to cover the front side of the push button and that enables the push button to be pressed when a predetermined or greater pressure is applied from the front side, and has an attachment part that is attached to the device body, and a front protective part that is provided on the attachment part and covers the front side of the push button cover (Claim 1).

The mounting portion is removably attached to the device body (Claim 2).

Furthermore, a peripheral protection part is provided on the mounting part and covers the periphery of the push button cover (Claim 3).

The peripheral protection section has a cutout portion that opens downward, and the push button can be operated through the cutout portion (Claim 4).

The alarm device of the present invention is provided with a protective cover for an alarm device as described in any one of claims 1 to 4 (claim 5).

The present invention provides a protective cover for an alarm device and an alarm device that can prevent malfunctions caused by the push button of the alarm device being pressed unintentionally.

1 is a front view showing an alarm device to which a protective cover for an alarm device according to one embodiment of the present invention is attached. FIG. 2 is a view taken in the direction of the arrow II in FIG. 1 . 3 is a cross-sectional view of a front portion of the alarm device, taken along the line III-III of FIG. 1 . 1 is a diagram illustrating a state in which an alarm device according to one embodiment of the present invention is installed in a thermal power plant, and malfunctions caused by coal falling from a conveyor belt are suppressed.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.
Fig. 1 is a front view of an alarm device 1 according to one embodiment. Fig. 2 is a view taken in the direction of the arrow II in Fig. 1, and is a side view of the alarm device 1. Fig. 3 is a cross-sectional view of the front part of the alarm device 1 corresponding to the line of sight of the arrows III-III in Fig. 1. In Fig. 1, the X direction indicates the left-right direction of the alarm device 1. Also, in Figs. 2 and 3, the Y direction indicates the front-rear direction of the alarm device 1, with the Y1 side indicating the front and the Y2 side indicating the rear. Also, in Figs. 1 to 3, the Z direction indicates the up-down direction of the alarm device 1. The alarm device 1 of this embodiment can be used, for example, as a fire alarm.

The alarm device 1 of this embodiment includes a device body 10, a push button 20, a push button cover 30, and an alarm device protective cover (hereinafter abbreviated as protective cover) 40.

As shown in FIG. 2, the device body 10 has a case 12 having a rectangular box shape and a lid 18. The case 12 opens forward in the Y1 direction in FIG. 2, and the opening is closed by the lid 18. The lid 18 is fixed to the case 12 by a number of screws 19 shown in FIG. 1.

The device body 10 is provided with an upper indicator light 14 and a front indicator light 16 for visually identifying the installation location of the alarm device 1. The upper indicator light 14 is disposed on the top surface of the case 12. The front indicator light 16 is disposed on the front surface of the cover body 18. The front indicator light 16 is disposed above a push button 20 that is disposed approximately in the center of the device body 10 in the vertical direction. For example, the upper indicator light 14 is configured as a red light, and the front indicator light 16 is configured as a white light.

The push button 20 emits a notification signal when pressed backward from the front side of the device body 10. The push button 20 is located on the front side of the device body 10, approximately in the center of the cover 18. As shown in FIG. 3, the cover 18 has a circular hole 18a, and the push button 20 is located at a position corresponding to this hole 18a.

As shown in FIG. 3, the cover 18 has a cylindrical boss 18b around the hole 18a. The boss 18b protrudes forward. The switch 24 is disposed in the area extending from the inside of the boss 18b to the hole 18a. The switch 24 has a switch body 24a and a switch pin 24b that protrudes forward from the switch body 24a and can move forward and backward. The switch pin 24b is biased forward by a biasing member such as a spring (not shown) provided inside the switch body 24a, and abuts against the back surface of the push button 20. The boss 18b has a male thread 18c on its outer circumferential surface. The switch body 24a has a recess 24c in the center of its front surface.

As shown in FIG. 3, the push button 20 is supported in a recess 24c of the switch body 24a so that it can slide in the forward and backward directions. The push button 20 is normally biased forward by the switch pin 24b and is held in the standby position shown in FIG. 3 by a stopper (not shown). In this state, the switch 24 is OFF. By pushing the push button 20 backward as shown in the Y2 direction in FIG. 3, the switch pin 24b is pushed backward and the switch 24 is turned ON. When the switch 24 is turned ON, for example, an alarm is issued or an alarm signal is sent to a specified monitoring station. The signal issued when the switch 24 is turned ON is sent via the cable 13 shown in FIG. 1 and FIG. 2.

As shown in FIG. 3, the push button cover 30 is supported on the inside of a cylindrical cap 32 that is attached to the boss portion 18b. The push button cover 30 is a protective cover that prevents the push button 20 from being unintentionally pressed. The push button cover 30 is made of a transparent resin plate. When the push button cover 30 receives a pressing force from the front side that is greater than a predetermined value, it breaks or is pressed in, thereby enabling the push button 20 to be pressed. The push button cover 30 is located on the front side of the inside of the cap 32, slightly behind the front end face of the cap 32.

The cap 32 has a female threaded portion 32c on its inner surface. The female threaded portion 32c is formed from approximately the center of the cap 32 in the front-to-rear direction to the rear end. The cap 32 is removably attached to the boss portion 18b by screwing the female threaded portion 32c into the male threaded portion 18c of the boss portion 18b. In this way, the push button cover 30 is positioned to cover the front side of the push button 20.

As shown in Figures 1 to 3, the protective cover 40 is arranged to cover the front side of the push button cover 30. The protective cover 40 has a rectangular box shape. The protective cover 40 has an attachment portion 41, a front protection portion 42, a peripheral protection portion 44, and a cutout portion 48. The protective cover 40 has the attachment portion 41, the front protection portion 42, and the peripheral protection portion 44 integrally molded from, for example, a transparent resin.

The mounting portion 41 is a portion that is detachably attached to the lid 18 of the device main body 10, and constitutes the rear portion of the protective cover 40. The mounting portion 41 is formed in a rectangular plate shape. As shown in FIG. 3, the mounting portion 41 has a circular fitting hole 41a in the center that fits into the boss portion 18b. The fitting hole 41a fits into the boss portion 18b, and the back surface of the mounting portion 41 abuts against the front surface of the lid 18.

As shown in FIG. 3, the front protective part 42 is disposed at a predetermined distance in front of the mounting part 41, and covers the front side of the push button cover 30. The front protective part 42 is formed in a rectangular plate shape of approximately the same size as the mounting part 41, and is disposed parallel to the mounting part 41. The distance in the front-to-rear direction between the front protective part 42 and the push button cover 30 is arbitrary, but at least a distance is ensured that the push button cover 30 and the push button 20 can be pressed with the fingers without interfering with the front protective part 42.

The perimeter protection part 44 is disposed between the mounting part 41 and the front protection part 42 and connects the mounting part 41 and the front protection part 42, and covers the perimeter of the push button cover 30. As shown in Figs. 1 to 3, the perimeter protection part 44 has a pair of left and right side plate parts 45, 46 and an upper plate part 47 that connects the upper ends of the side plate parts 45, 46. Each of the side plate parts 45, 46 is formed in a rectangular plate shape. Each of the side plate parts 45, 46 is formed between each end on both the left and right sides of the mounting part 41 and each end on both the left and right sides of the front protection part 42. The upper plate part 47 is formed in a rectangular plate shape. The upper plate part 47 is formed between the upper end of the mounting part 41 and the upper end of the front protection part 42. The side plate portions 45, 46 and the top plate portion 47 are perpendicular to the mounting portion 41 and the front protective portion 42, which gives the protective cover 40 a rectangular box shape.

The cutout 48 is an opening inside the peripheral protection section 44 that opens the inside of the protective cover 40 downward. In the alarm device 1, the push button 20 can be pressed by a finger inserted into the cutout 48 of the protective cover 40 from below. It is preferable that the opening area of the cutout 48 is large enough to prevent fallen coal C1, described below, from entering the inside of the protective cover 40.

The protective cover 40 is fastened to the front of the lid 18 by fitting the fitting hole 41a of the mounting part 41 into the boss part 18b with the cap 32 removed, screwing the female threaded part 32c of the cap 32 inserted into the inside of the protective cover 40 from the cutout part 48 into the male threaded part 18c of the boss part 18b, screwing the cap 32 backward, and pressing the mounting part 41 against the lid 18 with the cap 32, thereby fastening it to the front of the lid 18. The protective cover 40 is fixed to the lid 18 so that the cutout part 48 is positioned downward.

In this fixed state, the protective cover 40 is arranged so that the mounting portion 41 and the front protective portion 42 are approximately along the XZ plane formed by the X-axis and Z-axis, the side plate portions 45, 46 are approximately along the YZ plane formed by the Y-axis and Z-axis, and the upper plate portion is approximately along the XY plane formed by the X-axis and Y-axis. The lower edges of the side plate portions 45, 46 of the front protective portion 42 and the perimeter protective portion 44 are positioned below the push button cover 30 so as to completely cover the push button cover 30.

In the alarm device 1 according to this embodiment, the front side of the push button cover 30 is covered with the protective cover 40, so that the push button cover 30 is unintentionally pressed and the push button 20 is prevented from being pressed erroneously. Therefore, for example, if the alarm device is installed as a fire alarm near a conveyor belt at a thermal power plant where falling coal occurs, false activation due to falling coal is prevented.

Figure 4 shows the case where the alarm device 1 according to this embodiment is installed as a fire alarm in a thermal power plant. In Figure 4, the alarm device 1 is installed on a wall W adjacent to the belt conveyor 100, which transports coal C. Figure 4 shows the belt conveyor 100 in a front cross-sectional view.

The belt conveyor 100 has a belt 110 that moves in the front-to-back direction in FIG. 4. Both front-to-rear ends of the belt 110 are wound around rollers (not shown), and coal C placed on the upper conveying belt 110a is conveyed, for example, in the back direction of the drawing. The belt conveyor 100 has a conveying side conveyor roller 120 that supports the conveying side belt 110a from below, and a return side conveyor roller 122 that supports the return side belt 110b of the belt 110 from below. Multiple conveyor rollers 120, 122 are arranged along the belt 110.

The transport side conveyor roller 120 includes three divided rollers 120a divided in the width direction of the belt 110 (left and right direction in FIG. 4). Each of the three divided rollers 120a is rotatably supported above the base 130 via a plurality of support frames 132. The return side conveyor roller 122 is rotatably supported below the base 130 via a plurality of support frames 134. The base 130 is disposed above the floor F via a plurality of legs 136.

The belt conveyor 100 is provided, for example, on a route for transporting coal C from a coal silo to a boiler. In the belt conveyor 100, there is a risk that the coal C or coal fines dispersed from the coal C may ignite due to frictional heat generated during operation. Therefore, the alarm device 1 according to this embodiment is installed as a fire alarm on a wall W on the side of the belt conveyor 100, with the push button 20 facing in the direction of the belt conveyor 100.

When coal C is loaded from a coal silo onto the belt conveyor 100, or during the process of transporting coal C on the belt conveyor 100, as shown in FIG. 4, coal C falls from the belt conveyor 100 onto the floor F, resulting in coal fall C1, which may bounce off the floor F and head toward the alarm device 1. Conventionally, such coal fall C1 may hit the exposed push button cover and cause the push button to be pressed, resulting in a malfunction. However, in the alarm device 1 of this embodiment, the front side of the push button cover 30 is covered with the protective cover 40, so that the coal fall C1 bounces off the protective cover 40 as shown in FIG. 4. This prevents the coal fall C1 from hitting the push button cover 30, and suppresses the malfunction of the push button 20 being pressed. Even if the protective cover 40 is damaged by fallen coal C1 and the fallen coal C1 hits the push button cover 30, the force of the falling coal C1 is attenuated by hitting the protective cover 40, preventing the push button cover 30 from being pressed and causing a malfunction.

In the protective cover 40 of this embodiment, fallen coals C1 hit the front protection part 42 that covers the front side of the push button cover 30, thereby preventing the fallen coals C1 from hitting the push button cover 30. Also, if fallen coals C1 fly in from the side of the push button cover 30, the fallen coals C1 hit the side plate part 45 or the side plate part 46 of the surrounding protection part 44, and are prevented from hitting the push button cover 30. Also, if fallen coals C1 fly in from above the push button cover 30, the fallen coals C1 hit the upper plate part 47 of the surrounding protection part 44, and are prevented from hitting the push button cover 30.

When fallen coals C1 hit the push button cover 30 from the front side, the impact is large and it is easy for malfunction to occur, but the collision of fallen coals C1 with the push button cover 30 from the front side is prevented by the front protection part 42. In addition, the surrounding protection part 44, which includes the side plate parts 45, 46 and the upper plate part 47, prevents the falling coals C1 flying from the sides and above the push button cover 30 from colliding with the push button cover 30.

If the protective cover 40 is damaged by the fallen coal C1 and is no longer able to fully protect against the fallen coal C1, the cap 32 screwed to the boss portion 18b is removed, the mounting portion 41 is pulled out from the boss portion 18b, the protective cover 40 is removed from the lid body 18, and then replaced with a new protective cover 40. The mounting portion 41 of the protective cover 40 is detachably attached to the lid body 18, making replacement easy.

The protective cover 40 according to the present embodiment described above provides the following advantages.
The protective cover 40 in this embodiment is provided on an alarm device 1 which comprises a device main body 10, a push button 20 which is provided on the device main body 10 and which activates the transmission of an alarm signal when pressed, and a push button cover 30 which is arranged to cover the front side of the push button 20 and enables the push button 20 to be pressed when a predetermined amount of pressure or more is applied from the front side, and has an attachment portion 41 which is attached to the device main body 10, and a front protective portion 42 which is provided on the attachment portion 41 and covers the front side of the push button cover 30.

This prevents flying objects such as fallen coal C1 as described above from hitting the push button cover 30, causing the push button 20 to be pressed unintentionally, and allows the push button 20 to be manually pressed only when an alarm is required. The front protective section 42 effectively prevents flying objects from colliding with the push button cover 30 from the front side.

In the protective cover 40 according to this embodiment, the attachment portion 41 is removably attached to the device body 10.

As a result, when the protective cover 40 becomes damaged and needs to be replaced, the mounting portion 41 can be attached and detached to the device main body 10, so that it can be easily replaced with a new protective cover 40.

The protective cover 40 according to this embodiment further includes a peripheral protective part 44 that is provided on the mounting part 41 and covers the periphery of the push button cover 30.

This prevents flying objects from colliding with the push button cover 30 from around the cover, further improving the protective function.

In the protective cover 40 according to this embodiment, the peripheral protective portion 44 has a cutout portion 48 that opens downward, and the push button 20 can be operated through the cutout portion 48.

This allows the push button 20 to be pressed to sound an alarm without removing the protective cover 40 from the device body 10.

The device 1 according to this embodiment is equipped with the protective cover 40 described above, and therefore can prevent flying objects such as fallen coal C1 as described above from hitting the push button cover 30, which would cause the push button 20 to be unintentionally pressed, resulting in a malfunction. The push button 20 can be manually pressed only when a notification is required.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and includes modifications, improvements, etc. within the scope of achieving the object of the present invention.

For example, the protective cover 40 in the above embodiment is shaped like a rectangular box, but the surrounding protection part 44 may be cylindrical, so that the entire cover is formed into a cylindrical shape. Also, the mounting part 41 in the above embodiment is detachable from the lid 18 of the device body 10 by fastening it together with the cap 32, but the configuration for making the mounting part 41 detachable is not limited to this, and a simpler configuration may be used, such as detachably engaging a protrusion such as a claw formed on the mounting part 41 with a hole in the lid 18.

The alarm device 1 according to this embodiment can be used as a fire alarm in a thermal power plant as described above, but it can be installed anywhere and can be used as an alarm device for various purposes other than fire.

REFERENCE SIGNS LIST 1 Notification device 10 Device body 20 Push button 30 Push button cover 40 Protective cover 41 Mounting portion 42 Front protective portion 44 Surrounding protective portion 48 Cutout portion

Claims (5)

A device body,
a push button provided on the device body, the push button being operated to activate transmission of a notification signal;
A push button cover is arranged to cover the front side of the push button and enables the push button to be pressed when a predetermined or greater pressing force is applied from the front side. A protective cover is provided for an alarm device installed on the side of a coal conveyor belt in a thermal power plant ,
A mounting portion that is attached to the device body;
A front protection part is provided on the mounting part and covers a front side of the push button cover ,
A protective cover for an alarm device , wherein the front protective portion is integral with the mounting portion and is fixed to the device body together with the mounting portion when the mounting portion is attached to the device body. The protective cover for an alarm device according to claim 1, wherein the mounting portion is detachably attached to the device body. The protective cover for an alarm device according to claim 2, further comprising a peripheral protective part provided on the mounting part and covering the periphery of the push button cover. The protective cover for an alarm device according to claim 3, wherein the peripheral protection part has a cutout part that opens downward, and the push button can be operated through the cutout part. An alarm device equipped with a protective cover for an alarm device according to any one of claims 1 to 4.

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