JPS6119765Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a sand raking machine that prevents siltation in sand settling basins, and its purpose is to prevent dirt from adhering to the conveyor frame, and to increase strength by reducing the amount of reinforcing material.
Another purpose is to prevent the raking machine from overloading even if the amount of sediment is small and the amount of raking by each bucket is small, or even if a large amount of sand temporarily flows in during rain and the bucket becomes buried. The purpose is to ensure that the sand is raked up smoothly while preventing heavy loads from being applied.

Conventionally, a bucket conveyor frame was placed along the bottom of the sand settling basin. Sprocket wheels were installed at the front and rear ends of the frame, and an endless bucket conveyor was strung between these wheels and the wheels above the pond. In the raking machine, the bucket conveyor frame is used as a link to prevent the bucket from being buried and to smoothly raise the sand even when the bucket is temporarily buried due to strong inflow of earth and sand such as during rain. When a load is applied to the bucket conveyor, the links are swung so that the conveyor frame is moved backward and raised.

Therefore, in this method, when an overload is applied to the bucket conveyor, the bucket conveyor frame can swing in the backward direction to escape the overload, but the amount of sand lifted by each bucket is small and the load is too large. However, if the link swings when even a small load is applied to the conveyor frame, there is a drawback that the sand cannot be raked up by the bucket.

For this reason, in the above-mentioned type of sand and scraper, there has been a problem in how to set the load for the conveyor frame to retreat. Another disadvantage is that a large amount of dirt adheres to the conveyor frame underwater.

In view of this, the present invention increases the strength of the conveyor frame, reduces the adhesion of garbage, and when the load of sand raking by each bucket is less than the set raking amount, the conveyor frame does not retreat and operates normally. It maintains its position and swings backwards when overloaded, allowing smooth raking even when the amount of sand raking is small or when the bucket conveyor is buried. be.

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. A bucket chain 2 for sand raking, which is attached to a sand trap, is stretched, and this bucket chain 2 is attached to a bucket of a required length along the bottom of the pond in the water of the sediment basin, and in the front and back direction of the basin, as detailed in Fig. 1. Place the conveyor frame 3,
Support shafts 3 are attached to both the front and rear ends of this conveyor frame.
Submersible sprocket wheels 5a and 5b are rotatably provided via a and 3b, respectively, and guide shafts 4a and 4b are provided above the water, and guide sprocket wheels 6a and 6b are provided on each guide shaft, respectively. In addition, a take-up shaft 7a and a drive shaft 8a are also provided, and sprocket wheels 7 and 8 for take-up and drive are provided on each shaft, respectively, and these wheels 5a, 5b, 6b, 6a, 7,8
The bucket chain 2 is meshed and stretched between them.
In this case, another sprocket wheel 6c may be provided between the sprocket wheels 6b and 5b. Further, one or more chain guides 3c are vertically provided between the sprocket wheels 5a and 5b at both ends of the bucket conveyor frame 3, and the roller portion of the bucket chain 2 is supported by the chain guides 3c. This chain guide 3c is a bracket 3 protruding from the bucket conveyor frame.
d, and between the chain guides 3c and 3c, and between the sprocket wheels 5a or 5b at both ends and the adjacent chain guide 3c, even when the frame is hoisted or raised, the bucket chain 2 will not move due to its own weight, etc. It is determined so that the amount of droop is within the allowable range. Therefore, if the frame length is large, the number of chain guides will also be large.

The bucket conveyor frame 3 has a pipe shape so that it is difficult for underwater debris to adhere to it, and the lower ends of a front link 9 and a rear link 10 are pivotally connected at the front and rear parts of the frame, respectively. Shafts 9a, 10 with the upper ends of 9, 10 provided in the settling basin
When the bucket conveyor frame 3 is in the sand raking position, that is, along the pond bottom, the links 9 and 10 are moved back by an angle θ from the vertical position as shown in FIG. Stoppers 13a, 13a are provided on the upstream side of the links 9, 10 so that the links 9, 10 can be supported in a tilted state, and the links are brought into contact with each other. The front link 9 and the rear link 10 may have the same overall length, but the front link 9 is made shorter so that the front part of the frame 3 is lifted more than the rear part,
It is possible for the rear link 10 to vary in its length.

The drive shaft 8a is equipped with a drive device M, which drives the drive sprocket wheel 8 at a required speed, drives the bucket chain conveyor, and scrapes up the sand. It is also possible to make it adjustable. Below between the drive sprocket wheel and the take-up sprocket wheel, there is a tray for discharging the sand scraped up by each bucket by the bucket conveyor by tilting the bucket, and to discharge it to the outside of the settling basin. A carry-out machine 11 is provided. At this time, if necessary, a bucket cleaning nozzle may be provided.

A guide 1 is placed above the guide sprocket wheel 6a provided on the first guide shaft 4a in a substantially horizontal direction.
2, a take-up shaft 7a that slides on the guide 12 is provided, a take-up sprocket wheel 7 is provided on this take-up shaft, and the wheel 7 is slid on the shaft 7a with a take-up thread 7b to connect the bucket chain. This prevents the chain from sagging and keeps the tension of the chain almost constant during normal operation.

In the above-mentioned sand settling machine, when sediment, etc. flows into the sand settling basin and accumulates on the bottom of the basin above a certain level, the drive device M is driven, and thereby the bucket chain is moved through the drive sprocket wheel 8. 2 is driven, and the sand is raked up by each bucket B.
It is discharged outside the pond by a discharger 11 (consisting of a chute, a conveyor, etc.). Incidentally, the bucket conveyor may be constantly driven regardless of the amount of sediment. 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 at 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,
The sand will be raked up. In this case link 9,1
0 is supported in contact with the stopper 13a at a position retreated by an angle θ from the vertical position, but the conveyor frame is subjected to a force F to advance the link to the vertical position.
is working. The forward force F of this conveyor frame
is expressed by the following equation, assuming that the weight of the conveyor frame 3 is W, and the angle θ formed by the links 9 and 10 when they are supported in contact with the stopper 13a is θ.

F=W×tanθ The tension of the bucket conveyor applied to the sprocket wheel 5a is T in the vertical direction and T in the horizontal direction, and the resultant force is T'.
This resultant force T' acts as a resistance force during sand raking, and acts as a force that causes the conveyor frame to retreat. When the relationship between this resultant force T' and the forward force F of the conveyor frame is expressed by the following formula, that is, F=
When T', the conveyor frame is held in its normal position as shown by the solid line in FIG. 1 even if the bucket conveyor is used to lift up the sediment. Therefore, the conveyor frame does not retreat and the sand raking is carried out normally until the raking amount reaches the set load. If the amount of sediment flowing into the settling basin increases due to rain, etc., part or all of the bucket conveyor, which is stopped or in operation, may be buried by the sediment. 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 applied to the conveyor frame increases accordingly. Due to this increase in reaction force, the conveyor frame 3, which has been stopped at the normal position, moves backward in the direction of the reaction force. That is, when F<T', the conveyor frame moves backward. This is because the conveyor frame is supported by two front and rear links whose upper ends are pivoted to the fixed side of the pond, so the conveyor frame moves backward as shown by the chain line in Figure 1 until the links come into contact with the rear stopper 13b. At the same time, the bucket conveyor is lifted upward, and the bucket conveyor is lifted together with the conveyor frame by the chain guide to be located above the sand settling, and the overload is released and sand raking is carried out with normal torque. . As the raking occurs, the relationship between the forward force F of the conveyor frame and the raking resistance force T' gradually changes, and the conveyor frame gradually descends. This allows sand to be raked up smoothly under normal load at all times.

In the above embodiment, the frame 3 floats naturally due to 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. It can also be made to wait at a certain position.

According to the present invention, the bucket conveyor is stretched and the links are supported at an angle so that the conveyor frame, which is placed along the pond bottom, is suspended at a predetermined angle. Therefore, since a constant forward force is always applied to the conveyor frame, that is, a force in the opposite direction to the reaction force generated by raking, the conveyor frame will not move until the amount of sand raking by the bucket reaches the set amount. Since it does not back up, raking can be performed reliably, and even if the bucket conveyor becomes buried or the raking load exceeds the normal value due to consecutive holidays or a temporary increase in inflowing sediment, the conveyor frame will prevent the increase in load on the bucket conveyor. The bucket conveyor rises naturally due to the reaction force, and the load on the bucket conveyor is always adjusted to the normal value, allowing for smooth sand raking, and the pipe-shaped conveyor frame makes it difficult for submerged debris to stick to the conveyor. Also, since this garbage is often around 30 cm, the diameter of the pipe should be
If the length is 300 mm or more, the effect will be further improved, and the strength will be increased, so there are advantages such as less need for other reinforcing materials.

[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 chain, 3a,
3b...Support shaft, 3c...Chain guide, 4a,
4b... Guide shaft, 5a, 5b... Underwater sprocket wheel, 6a, 6b... Guide sprocket wheel, 7... Take-up sprocket wheel, 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, 13a, 13
b...Stopper, B...Bucket, M...Drive device.

Claims (1)

[Scope of utility model registration request] A bucket conveyor is drivably suspended in a sand settling basin so as to scrape up sand, and the supporting shafts of submersible sprocket wheels on the upstream and downstream sides of the bottom of the sand settling basin which engage the chain of this bucket conveyor are attached to the basin. In a sand raking machine with a bucket conveyor frame installed in the bottom, the bucket conveyor frame is swung in the backward direction of the conveyor frame by links that are tilted backward at a certain angle at the front and back of the frame. The conveyor frame supports the bucket conveyor freely and prevents it from floating due to the reaction force applied to the bucket conveyor during normal raking operation, and when a reaction force greater than that during normal raking operation is applied to the bucket conveyor, the conveyor frame is designed to absorb the reaction force. Therefore, the support angle is determined by the link of the conveyor frame so that the conveyor frame swings upward while moving backward, and a chain guide is suspended from the middle part of the bucket conveyor frame to support it so as to receive the rollers of the bucket chain. A sand raking machine featuring: