JPH074936U - Sprocket with shear pin - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a sprocket with a shear pin that does not come off even under a large thrust load and that can be easily attached and detached. [Composition] A magnet is fitted under the head of the shear pin,
A plate is provided on the end face of the shear pin head, a gap is maintained between the plate and the end plate with tongue, which is superposed on a partial plane of the plate.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a sprocket with a shear pin in which a hub and a sprocket are joined together by a shear pin to prevent overload.

[0002]

[Prior art]

 In a conventional sprocket with a shear pin, the shear pin is sheared when the shear pin penetrates into a hole formed in the hub flange and the sprocket with the same diameter and is integrated, and the sprocket is overloaded. The edge was cut, the rotation of the sprocket stopped, and this was detected by, for example, a proximity switch, and the motor was stopped. However, since the shearpin often came out due to vibration, in order to improve this, a magnet was attached under the head of the shearpin, and the magnetic force of the magnet secured the shearpin to the sprocket to prevent the shearpin from slipping out. Was there.

[0003]

[Problems to be solved by the device]

 However, if the magnet's attractive force is too strong, foreign matter will adhere to the sprocket more often, and moreover, foreign matter will be caught between the teeth of the sprocket and the chain, causing the chain to fall off. There is a limit to the suction force, and it is necessary to make the suction force slightly larger than the shearpin's own weight, but there was the problem that the shearpin would come off when an unexpectedly large thrust load was applied. It is an object of the present invention to provide a sprocket with a shear pin that does not come off even under a large thrust load and is easy to attach and remove.

[0004]

[Means for Solving the Problems]

 A sprocket is rotatably fitted to the outer periphery of the hub fixed to the drive shaft, and in a sprocket with a shear pin in which the hub and sprockets are united by a shear pin, a magnet is fitted under the shear pin's head and A plate is screwed onto the end face of the shear pin, and a tongue end plate is screwed onto the tip of the drive shaft so that a partial plane of the plate and the tongue of the end plate overlap with each other with a predetermined gap. It is characterized by being provided.

[0005]

【Example】

 Examples will be described with reference to the drawings. In FIG. 1, a hub 4 with a rotatable sprocket 3 having a bush 2 on its inner diameter is attached to a drive shaft 1 via a key 5.

The sprocket 3 and the flange 14 of the hub 4 are provided with holes 15 and 16 each having a bush 6 with the same circumferential diameter at one location.

A magnet 8 is fitted under the head of the shear pin 7, a square plate 10 is attached to the head end of the shear pin 7 with a butterfly bolt 9, and the shear pin 7 is inserted into the holes 15 and 16 so that the magnet 8 The shear pin 7 is fixed to the sprocket 3 by the suction force.

A collar 11 presses the sprocket 3 to prevent the sprocket 3 from falling off the hub 4.

In order to prevent the hub 4 from coming out of the drive shaft 1, the end plate 12 is screwed to the tip of the drive shaft 1 and the tongue 13 formed on the end plate 12 serves as the square plate 10. Hold the gap G by 1 mm so that they overlap.

Next, the operation of the above configuration will be described. Even if an attempt is made to get out of the shear pin 7 by applying a thrust load larger than the attractive force of the magnet 8 fitted under the head of the shear pin 7, the square plate 10 mounted on the end face of the shear pin 7 via the chow bolt 9 Since the tongue portion 13 of the square tongue end plate 12 is provided so as to overlap with a part of the gap G1 mm, even if the shear pin 7 is pulled out by 1 mm, the square end plate 10 does not change from the square tongue end plate 12 to There is no danger of hitting the tongue portion 13 and coming off further. Moreover, when the thrust load is released, the shear pin 7 can be restored to the original mounting position by the attractive force of the magnet 8.

Next, the replacement work when the shear pin 7 is sheared due to overload is performed as follows. First, the holes 15 and 16 of the sprocket 3 and the hub 4 are aligned with each other, and the cut piece of the shear pin 7 in the hole 15 of the sprocket 3 is extracted. This can be done easily by hand. Next, a new shear pin 7 is inserted into the hole 15 of the sprocket 3 and further pushed into the hole 16 of the hub 4. By doing so, the cut pieces of the shear pin 7 remaining in the hole 15 of the hub 4 are pushed out by the new shear pin 7. Next, the square plate 10 is attached to the head end surface of the shear pin 7 with the stud bolt 9. At that time, since the square plate 10 and the tongue 13 of the square tongue end plate 12 are overlapped with each other with a gap of 1 mm, the square plate 10 is not disassembled and the square plate 10 is not disassembled. Can be installed.

[0012]

[Effect of device]

 According to the present invention, the attraction force of the magnet mounted under the head of the shear pin and the square plate and the square tongue end plate prevent the shear pin from coming off even under a large thrust load, and the shear pin can be easily attached and detached. You can

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a sprocket with a shear pin.

FIG. 2 is an arrow view of a main part of AA of FIG.

[Explanation of symbols]

 1 Drive Shaft 2 Bushing 3 Sprocket 4 Hub 5 Key 6 Bushing 7 Shear Pin 8 Magnet 9 Butterfly Bolt 10 Square Plate 11 Color 12 Square Tongue End Plate 13 Tongue 14 Flange 15 Hole 16 Hole

Claims (1)

[Scope of utility model registration request] 1. In a sprocket with a shear pin, in which a sprocket is rotatably fitted to the outer periphery of a hub fixed to a drive shaft, and the hub and the sprocket are integrally joined by a shear pin, a magnet is fitted under the head of the shear pin. The plate is screwed onto the end face of the shearing pin, and the end plate with tongue is screwed onto the tip of the drive shaft. A sprocket with a shear pin that is provided so that