JPH0120705Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a device that easily and reliably detects the breakage of a stretched chain.

[Problems to be solved by the prior art and the invention]

Conventionally, in order to prevent warm and cold air from escaping outside as much as possible in large areas such as factories, for example, a sheet shutter was installed on the indoor side in opposition to the normally used metal shutter, and metal shutters were used during working hours. Sheet shutters that can be opened and closed at high speed are used when workers, trucks, forklifts, etc. enter and exit with the manufactured shutters open. As shown in Fig. 1, this seat shutter has a shaft 2 connected to an opening/closing machine 1 above an open doorway, and a seat 3 whose upper end is attached to the top of the doorway whose upper end is open. In addition to the belt method, which uses a belt to raise and lower the machine, for larger products, the chain method uses a chain. In this latter chain system, a drive sprocket 5 fixed to the shaft 2 is fixed to the outer right and left positions of the seat 3, and a driven sprocket 6 is arranged below the drive sprocket 5, and the driven sprocket 6 and The drive sprocket 5
An endless chain 4 is suspended between them, and the chain 4
Then, the counterweight 7 and the support member 9 that supports the bottom 8 to which the lower end of the seat 3 is attached are fixed, and the drive sprocket 5 is driven to raise and lower the bottom 8, and the bottom 8 is raised and lowered by ultrasonic, photoelectric, or wireless operation. It automatically controls the opening and closing of the seat in a short time.

Therefore, the seat opens and closes at a high speed, so if the chain breaks, especially in the case of a double chain drive system as shown in Figure 1, the seat will continue to open and close at high speed with another chain that will not break, and the load will be unloaded. This is extremely dangerous as other chains may be damaged one after another due to the balance, leading to a major accident. For this purpose, when detecting chain breakage, a chain 4 stretched as shown in FIG. A method is adopted in which the switch 1 is stopped by turning off the contact 11 using a micro switch 10 placed opposite the lever 14.
That is, in the case of FIG. 2, when the chain 4 is broken, the lever 14 in contact with the chain is rotated by the tension spring 12 around the shaft 13, pushing the contact 11 and cutting off the electrical circuit to the switch 1. This method has the drawback that the chain shakes due to the impact when stopping or starting, resulting in false detection.Also, it is necessary to install one detector for each chain, so if the chain is double, four detections will be required. equipment must be installed.

[Means for solving problems]

In view of these circumstances, the present invention solves these problems and provides a detection device that is inexpensive, uses a small number of devices, and can detect reliably. Fixed and hung,
A bottom is attached to the other end, and this bottom is attached to a chain hanging from a drive sprocket that is fixed to a shaft that is suspended horizontally above the entrance and connected to an opening/closing machine, and the seat is raised and lowered by the drive of the drive sprocket. At the lower part of the seat shutter that opens and closes the entrance and exit, corresponding to the chain, there is a detector consisting of a box housing a micro switch inside and a lid of the box that acts on the micro switch through a cushion material. This is a chain breakage detection device for a sheet shutter, characterized by the fact that

〔Example〕

Next, an embodiment of a chain breakage detection device for a sheet shutter according to the present invention will be described with reference to the drawings.

In the embodiment shown in FIGS. 3 and 4, two driving sprockets 5, 5 and 2 are used, unlike the conventional example shown in FIG.
It has a double chain structure in which two driven sprockets 6, 6 are connected to two chains 4, 4, and the fifth
In the example shown in the figure, a counterweight 7 is attached to one end of one drive sprocket 5, and an end chain to which a support member 9 of the bottom 8 is fixed is hung to the other end. Detector 1
5 is placed.

The detector 15 has a micro switch 1 inside the box 16.
7, one end side is pivotally connected to the box body, and the other free end side is connected to the box body 16 via a cushion material 18 such as rubber.
The lid 19 is made of elastic material, and when the chain 4 is pushed up by the cushion material 18 and cut, the chain 4 falls onto the lid 19, and the cushion material 18 is contracted by its weight to close the lid. At step 19, the micro switch 17 is pressed to make a notification. In the figure, 20 indicates a bearing of the shaft 2.

[Effect]

As described above, the present invention detects disconnection when the chain 4 stretched over the drive sprocket 5 breaks and falls, so when the chain breaks and falls,
The chain 4 falls onto the lid 19 that constitutes the detector 15 located at the bottom, and the cushion material 18 is contracted by the weight of the chain 4, and a micro switch inside the box body 16 corresponding to the lid 19 is activated. 17 is activated to stop the switch 1 and detect the disconnection of the chain 4.

〔effect〕

In this invention, as mentioned above, one end of a sheet composed of a wide flat surface is fixed and suspended above the open doorway, and the lower end of this sheet is suspended horizontally over the top of the doorway and connected to the opening/closing machine. In a seat shutter, which is attached to the bottom attached to a chain suspended from a drive sprocket fixed to a driven shaft, and which raises and lowers the seat by driving the drive sprocket and opens and closes an entrance/exit, the seat shutter corresponds to the chain of the seat shutter. In a seat shutter characterized by a detector consisting of a box housing a microswitch inside and a lid of the box that acts on the microswitch through a cushion material, located at the bottom. This is a chain break detection device, and when a broken chain falls, it is detected by detecting a drop on the lid of the detector, which consists of a box with a built-in micro switch located at the bottom, and a lid with a cushion material that acts on the micro switch. The weight of the chain activates the microswitch through the lid, so the detection action is reliable and direct.Also, even if the chain is in multiple rows, increasing the surface area of the lid allows only one detector to be activated. It can be detected with less detection than conventional methods, and there are practical benefits.

[Brief explanation of drawings]

Figures 1 and 2 show a known sheet shutter.
FIG. 1 is a front view, FIG. 2 is a side view, FIG. 3 is a front view showing an embodiment of the chain break detection device according to the present invention, FIG. 4 is a side view, and FIG. It is a side view showing an example. 1... Opener, 2... Shaft, 3... Seat, 4... Chain, 5, 5... Sprocket,
6, 7...Counterweight, 8...Bottom, 9
... Support member, 15 ... Detector, 16 ... Box body,
17...Micro switch, 18...Cushion material, 19...Lid, 20...Bearing.

Claims (1)

[Scope of utility model registration request] One end of the sheet was fixed to the top of the open doorway and suspended, a bottom was attached to the other end, and this bottom was fixed to a shaft suspended above the doorway and connected to the opening/closing machine. At the lower part of the seat shutter that corresponds to the chain, the seat shutter is attached to a chain suspended from the drive sprocket, and is driven by the drive sprocket to raise and lower the seat and open and close the entrance/exit.
Chain break detection in a seat shutter characterized by a detector consisting of a box housing a micro switch inside and a lid of the box that acts on the micro switch through a cushion material. Device.