JPS6216167Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a sand scraping machine that prevents a bucket conveyor frame from being buried in a sand settling pond. The slack in the chain is absorbed by the sagging of the bucket conveyor, and the chain is kept under tension to maintain a constant tension.

Conventionally, as an anti-siltation type sand scraper, there is a device in which one or both of the inlet and outlet sprocket wheels on which a conveyor with a bucket is stretched is moved upward by a hoist.

However, when the bottom sprocket wheel is moved, the chain of the bucket conveyor becomes slack.

For this reason, a chain slack absorbing device is installed in synchronization with the hoisting machine, but not only does this make the device bulky, but it is also difficult to maintain a constant tension by tensioning the chain according to the amount of slack.

The present invention will be described below based on embodiments shown in the drawings.

In the figure, 1 is a settling basin that is installed at a sewage treatment plant, etc., and allows rainwater, etc. to be introduced through street gutters, dark ditches, etc. Inside this settling basin 1, a large number of buckets B are placed in an endless chain at the required pitch. Stretch the bucket chain 2 for sand raking, which is attached with As detailed in FIG. 1, this bucket chain 2 has a bucket conveyor frame 3 disposed in the sand settling tank water in the front and back direction of the sand settling tank, and support shafts 3a and 3b are attached to both front and rear ends of the frame 3. An inlet sprocket wheel 5a and an outlet sprocket wheel 5b are rotatably provided at 3a and 3b, respectively, and guide shafts 4a and 4b are provided above the water, that is, above the pond, and each guide shaft has a guide shaft. In addition to providing sprocket wheels 6a and 6b, a take-up shaft 7a and a drive shaft 8a are also provided, and a take-up and a drive sprocket wheel 7 and 8 are provided on each shaft, respectively. 5
The bucket chain 2 is meshed and stretched between a, 5b, 6a, 6b, 7, and 8. Then, the slack is absorbed by the weight of the bucket conveyor between the driving sprocket wheel and the outflow side sprocket wheel, and this is used as the tension section of the bucket conveyor. Further, one or more chain guides 3c are vertically provided on the bucket conveyor frame 3 between the inflow side sprocket wheel 5a and the outflow side sprocket wheel 5b, and the roller portion of the bucket chain 2 is supported by the chain guide 3c. Do what you want. This chain guide 3c is provided at the lower end of a bracket 3d protruding from the bucket conveyor frame, and is installed between the chain guides 3c and 3c, and between the inflow side sprocket wheel 5a or the outflow side sprocket wheel 5b and the adjacent chain guide 3c. The interval is determined so that even when the frame is hoisted or raised, the amount by which the bucket chain 2 sags due to its own weight is within an allowable range. Therefore, if the frame length is large, the number of chain guides will also be large.

Further, the lower ends of the front link 9 and the rear link 10 are pivotally connected to the front and rear parts of the bucket conveyor frame 3, respectively, and the upper ends of the links 9 and 10 are provided in the sand basin or above the basin. 10a
Both the front and rear links 9,
When the bucket conveyor frame 10 is in a substantially vertical position or at a slightly receding angle, the bucket conveyor frame 3 is in the sand scraping position, that is, in a state along the pond bottom. The overall length of the front link 9 and the rear link 10 may be the same, but the lengths are set such that the front link 9 is short and the rear link 10 is long so that the front part of the frame 3 can be lifted more than the rear part. It is also possible to make them different.

The drive shaft 8a is equipped with a drive device M that drives the drive sprocket wheel 8 at a required speed, drives the bucket chain conveyor, and scrapes up the sand, but this drive speed is variable. It is also possible to make the capacity adjustable. Below between the driving sprocket wheel and the take-up sprocket wheel, the sand scraped up by each bucket by the drive of the bucket conveyor is discharged by tilting the bucket, and is also discharged to the outside of the settling basin. A discharge machine 11 is provided. At this time, if necessary, a bucket cleaning nozzle may be provided. A guide 12 is provided in a substantially horizontal direction above the guide sprocket wheel 6a provided on the first guide shaft 4a, a take-up shaft 7a that slides on this guide 12 is provided, and a take-up sprocket wheel 7 is mounted on this take-up shaft. is provided, and the wheel 7 is slid on the shaft 7a by a take-up screw rod 7b to prevent the bucket chain from sagging. This ensures that the tension in the chain is kept approximately constant during normal operation.

When the drive device M is driven in the above-mentioned sand scraper, the bucket chain 2 is driven via the drive sprocket wheel 8, and each bucket B
The sand is scraped up and discharged to the outside of the pond by a discharger 11. As the bucket conveyor is driven, a reaction force acts on the bucket conveyor frame, but during normal sand raking, the frame stops at the normal position or a position close to the normal position as shown by the solid line in Figure 1. In this state, only the bucket conveyor is driven and the sand is raked up. If the amount of sediment flowing into the settling basin increases due to rain, etc.,
A bucket conveyor that is stopped or running may be partially or completely buried by this inflowing earth and sand. If part or all of this bucket conveyor is buried in earth and sand, an excessive load will be applied to the driven bucket conveyor. The normal driving force is set to be greater than the driving force during normal operation, so even if a part of the bucket conveyor is buried, the bucket conveyor will not stop, but the driving force will be higher than the normal driving force. When a load is applied to the bucket conveyor, the reaction force increases accordingly. Due to this increase in reaction force, the frame 3, which has been stopped at the normal position, moves in the direction of the reaction force, that is, in the backward direction. This is supported by parallelogram-shaped front and rear links, so the frame is
As the bucket conveyor moves back and is lifted upward as shown by the chain line in the figure, the bucket chain is supported by a chain guide protruding from the frame, so that it is positioned above the settling sand without hanging down along with the frame. The overload is released and sand raking is carried out with normal torque, and as the raking occurs, the frame gradually descends due to its own weight. This allows for smooth sand raking under normal load at all times.

In this case, the chain is sprocket wheel 6b,
5b is slackened and hangs down a little to absorb changes in the length of the chains of wheels 8 and 5a due to the backward movement of the conveyor frame.

In the above embodiment, the frame 3 is naturally raised to the surface by the reaction force of the bucket conveyor, and remains at the bottom of the pond during standby, that is, when the bucket conveyor is stopped, but when the operation is suspended, the frame 3 is floated above the pond bottom. It can also be made to wait at a certain position.

According to the present invention, when the sprocket wheel on the inflow side is automatically swung by the link when a load greater than the set driving force is applied to the bucket, the slack generated by the oscillation is used for driving. The slack is absorbed by the weight of the bucket conveyor stretched between the sprocket wheel and the outflow side sprocket wheel, and has an excellent effect of keeping the tension of the chain constant at all times without the need for a separate slack absorbing device. .

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional front view, and FIG. 2 is a side view of the same. 1...Sand basin, 2...Bucket tin, 3a, 3b
... Support shaft, 3c... Chain guide, 3d... Bracket, 4a, 4b... Guide shaft, 5a... Inflow side sprocket wheel, 5b... Outflow side sprocket wheel, 6a, 6b... Guide sprocket wheel, 7
...Sprocket wheel for take-up, 7a...
Take-up shaft, 8... Drive sprocket wheel, 8a... Drive shaft, 9... Front link, 10... Rear link, 9a, 10a... Axis, 11... Discharge machine, 12... Guide, B... Bucket, M... Drive device.

Claims (1)

[Scope of utility model registration request] The chain of the bucket conveyor is stretched by the sprocket wheels on the inflow and outflow sides of the sand,
In this sediment scraper that scrapes up sediment from the pond bottom using a bucket conveyor, at least the inflow side sprocket wheel automatically swings when a load greater than the set driving force is applied to the bucket conveyor. A driving sprocket wheel is provided above the inflow side sprocket wheel, and the driving sprocket wheel and the pond bottom are connected to each other so as to absorb the slack caused by rocking by using the sag of the bucket conveyor. A siltation prevention type sand settling and scraping machine, characterized in that a tension section of a bucket conveyor is stretched between the sprocket wheels on the outflow side.