JPH0410052Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) The invention is based on the purpose of drawing identification characters, symbols, etc. on hot-rolled or cold-rolled coils, etc. immediately after rolling production to prevent mistakes from occurring in subsequent processes. This invention relates to improvements in marking devices.

(Prior Art) Conventionally, as one type of marking device, as shown in FIGS. 5 and 6, a lifting cart 2 is guided by a guide rail 3 of the post and raised and lowered by a chain 4 driven along an upright post 1. Equipped with
2. Description of the Related Art A marking device is known in which a marking head 6 for causing a marking tool such as a pen to perform a drawing motion is mounted on a horizontal arm 5 extending from a lifting cart 2.
In the illustrated example, the chain drive device includes a chain 4 whose one end is connected to the upper part of the lifting cart 2, which is folded back and guided downward by a sprocket 7 at the upper end of the post, and is connected to the drive sprocket 10 of the motor 8 and reducer 9 device at the lower part of the post.
The chain is then turned back and guided upwards, and the other end of the chain is connected to the lower part of the lifting truck.

(Problems to be Solved by the Invention) In the marking device of the prior art, if the chain were to break, the entire lifting device including the marking head of the precision machine would fall, potentially causing danger and serious damage. be.

SUMMARY OF THE INVENTION An object of the present invention is to provide a fast-moving guide rail clamping device that prevents a complete lifting device from falling even if the chain breaks.

(Means, effects, and embodiments for solving the problem) In order to achieve the above-mentioned object, the marking head drop prevention mechanism of the present invention is designed to prevent the marking head from falling along the post that is erected for marking cylindrical coil articles, etc. In a marking device, a horizontal arm is mounted on an elevating cart that moves up and down by a chain drive guided by a marking device, and a marking head is mounted on the horizontal arm to cause a marking tool to perform a drawing motion. A lock pawl is provided in the shape of a lever and held in a normal position almost orthogonal to the guide rail, and a drive chain is connected from above to the base end of the lock pawl, and a quick-motion tension spring is connected from below. It is characterized by forming a locking groove that fits into the guide rail while maintaining a small gap.

Hereinafter, the present invention will be explained in detail with reference to the embodiments shown in FIGS. 1 to 4. The marking head drop prevention mechanism of the present invention is installed in the part indicated by arrow A of the marking device in Figs. 5 and 6, and this marking device and the above description will be referred to as an example of the application form of the present invention. .

1, 2, and 3 show a side view, a top view, and a front view of the constituent parts of the proposed machine.

A bracket 11 is provided on the lifting carriage 2, and the middle part of a lever-shaped lock pawl 12 is pivotally supported to the bracket 11 by a pin 13. A chain 4 is connected to the base end of the lock pawl 12 from above, and a tension spring 14 for quick movement is connected from below between it and the lifting carriage.
A locking groove 15 is formed at the tip of the lock claw 12 so that it fits into the guide rail 3 of the post 1 as described below.

A centering pin 16 is provided on the lifting truck 2,
Opposing this, a conical receiving hole 17 is provided at the front lower part of the lock pawl. In a normal state where the chain 4 is not cut, the lifting cart 2 is suspended from the chain 4 by the weight of the lifting device, the base end of the lock claw 12 is pulled up, and the lock claw 12 is connected to the centering pin 16 and the receiving hole. 17 are fitted together to ensure reliable positioning, and the state shown by the solid line, which is almost perpendicular to the guide rail 3 of the post, is achieved. In this normal state, the engagement between the locking groove 15 and the guide rail 3 is as follows.
Ensure that a small gap of 0.5-1.0mm is maintained. Due to this gap, the lifting cart can be moved up and down smoothly.

If the chain 4 were to break, the lifting cart 2 would try to fall, but in the present invention, the base end of the lock pawl 12 is quickly pulled down by the quick-acting tension spring 14, and the fourth As shown in the figure, the tip part rises and the locking groove 15 is inclined with respect to the guide rail 3, the gap disappears, and both parts are pressed by a force p due to the tension spring force and the component force of the weight of the lifting device, forming a wedge. As a result of this effect, the lock pawl 12 becomes in a locked state where it clamps the guide rail 3, and the elevating carriage 2 does not fall thereafter. The tension of the tension spring 14 that achieves this quick and strong locking condition is
40-50Kg is appropriate.

If the initial tension of the tension spring is applied, the distance l between the upper and lower contact points between the lock pawl 12 and the guide rail 3 shown in FIG. 4 and the front lever length b of the lock pawl 12 will be l/b = 0.2 to 0.5. If the conditions are given, the above self-locking will work. The larger this value is, the stronger the locking force will be. In order to achieve reliable locking, the pin hole 18 in the middle of the lock pawl 12 is preferably made into a long hole to prevent unnecessary couple forces from acting.

Since the pressing force acting on the biting part of the locking pawl during locking is extremely large and also accompanied by a sliding phenomenon, this part of the pawl is preferably made of copper-based alloy or cast iron to prevent galling of the guide rail.

(Effects of the invention) According to the invention, even if the chain of a chain-driven lifting type marking device is broken, the lifting device part is reliably prevented from falling, thereby preventing harm and damage to the marking head, etc. Effects can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a side view of the marking head drop prevention mechanism according to an embodiment of the present invention, Fig. 2 is a plan view thereof, Fig. 3 is a front view thereof, Fig. 4 is a side view of the mechanism in a locked state showing its characteristic values, and Fig. FIG. 5 is a side view of one example of the marking device in its original state to which the present invention is applied, and FIG. 6 is a front view thereof. 1...Post, 2...Elevating trolley, 3...Guide rail, 4...Chain, 5...Horizontal arm, 6
...Marking head, 7...Sprocket, 8
... Motor, 9 ... Speed reducer, 10 ... Drive sprocket, 11 ... Bracket, 12 ... Lock pawl, 13 ... Pin, 14 ... Tension spring, 15 ...
...Latching groove, 16...Centering pin, 17...
Receiving hole, 18...pin hole.

Claims (1)

[Scope of utility model registration request] In order to mark cylindrical coil articles, etc., a horizontal arm is attached to an elevating cart that moves up and down by a chain drive along a post erected and guided by the post's guide rail, and a marking head is attached to the horizontal arm to cause a marking tool to make a drawing motion. In the mounted marking device, a lever-shaped locking pawl that is pivoted in the middle by a pin is mounted on the bracket on the lifting cart and is held in a normal position almost perpendicular to the guide rail, and a drive chain is attached to the base end of the locking pawl from above. A marking head drop prevention mechanism is characterized in that a fast-acting tension spring is connected from below, and a locking groove is formed at the tip of a locking pawl to fit into a guide rail while maintaining a small gap.