JP3375093B2 - Chain tensioning device and operation method for chain conveyor - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chain tensioning device and an operating method for a chain conveyor mounted on an off-loader, and more particularly, to a slip mounted on a shear loader equipped with an excavation bucket. The present invention relates to a chain tension device and a method of operating a chain conveyor to be transported.

[0002]

2. Description of the Related Art A conventional shear loader is provided with a base 2 on a self-propelled crawler 1 as shown in FIG. 3, and a chain conveyor 3 is pivotally attached to the center of the base 2 so as to be tiltable. The boom supporting frame 4 is horizontally rotatably attached to a boom open pivot pin vertically provided on the base 2 on the side of the front half of the conveyor 3, and the boom supporting frame 4 is attached to the base 2 on the base 2. Attach the boom open cylinder that is attached so that it can rotate. On the other hand, a support bracket 6 for supporting the rear boom 5 is provided at the tip of the boom support frame 4.
Is attached so as to be horizontally rotatable by a bucket pivot pin 7, and the boom support frame 4 and a support bracket 6 that supports the rear boom 5 are connected by a boom left / right swing cylinder 8. The rear boom 5 is vertically swingable with respect to the support bracket 7 by the cylinder 9, and the front boom 10 is pivotally attached to the tip of the rear boom 5 by the cylinder 11 so as to be vertically swingable. ing. A bucket 12 is pivotally attached to the front end of the front boom 10, and the bucket 12 can be vertically swung by a cylinder 14 via a link 13.

On the other hand, as shown in FIG. 4, the chain tensioning device of the chain conveyor 3 that conveys the slips is inserted into the supports 17 arranged on both sides of the conveyor trough 16 in which the scraper bar 15 is accommodated. The position of the sprocket 22 mounted on the drive shaft 21 on which the chain 20 of the chain conveyor 3 is suspended by the screw rod 18 and the pair of adjusting nuts 19 is set to the conveyor reducer storage box 23.
A screw type chain tensioning device that adjusts back and forth via a was known. Reference numeral 24 is a hydraulic motor for driving the conveyor chain, and reference numeral 28 is a pivot pin. Also, FIG.
As shown in FIG. 2, a pair of spring seats 25 are provided on the screw rod 18 of the screw type chain tensioning device, and a spring 26 is interposed between the spring seats 25, and a tension nut 27 is used to connect the chain 2 of the chain conveyor 3 to each other.
There is also known a spring-type chain tensioning device that adjusts the position of a sprocket 22 attached to a drive shaft 21 on which 0 is suspended via a conveyor reduction gear storage box 23 back and forth.

[0004]

However, in the above-mentioned screw type chain tensioning device, the screw rod 18 and the adjusting nut 1 are used.
9 is rusty and the adjustment work is very difficult, and the adjustment work by direct human power at a high place is dangerous,
There was a problem of long working hours. Further, when stones are caught in a chain or a sprocket and the chain is locked and stopped, there is no other means than reversing the conveyor to remove the jam.

Further, in the above spring type chain tension device,
There is no change in the adjustment work at a high place, and the adjustment work is dangerous, and the long work time is the same as the screw type work. In addition, even if a stone is caught in a chain or a sprocket and the chain locks and stops, there is no other way than to reverse the conveyor like the screw type.

Therefore, recently, the above various drawbacks have been improved so that the chain adjusting work can be performed safely and easily.
Moreover, even if the chain lock phenomenon occurs and the chain stops, there is a long-awaited development of a chain tensioning device for a chain conveyor that uses a scraper bar that can quickly eliminate the lock phenomenon.

The present invention has been made in view of the above circumstances and has a simple structure, which allows tension and release of the chain of the chain conveyor to be performed easily and quickly, and the chain adjustment work can be performed remotely. An object of the present invention is to provide a chain tension device and a method of operating a chain conveyor that can be safely performed.

[0008]

In order to achieve the above-mentioned object, the present invention provides a chain tensioning device for a chain conveyor that conveys scraps and the like by a scraper bar, in a hydraulic cylinder mounted on the side portion of the chain conveyor. , A front and rear two pistons are provided with a double piston that can expand and contract in the axial direction, the front and rear two pistons are separated from each other, and a spring for always tensioning the chain is attached to the front of the double piston. A chain tensioning device for a chain conveyor, characterized in that a piston rod of a positioned piston is connected to a chain tensioning sprocket side to guide hydraulic pressure to a front portion and a rear portion of a double piston in the hydraulic cylinder.

Further, in the chain tensioning / releasing operation method of the chain conveyor which conveys slips and the like by the scraper bar, in a hydraulic cylinder in which two pistons have built-in double pistons which can expand and contract with each other via a spring,
The rear side of the piston is pressed by the pressure oil from the hydraulic pump, and the tension of the conveyor is adjusted by the piston rod of the piston located in front of the double piston via the spring. When a jam occurs, the resistance is first received by the spring, and when the pressure oil exceeds a set value, the pressure oil is automatically released by a relief valve and a tension force above a certain value is not applied. On the other hand, when releasing the tension of the chain for repairing the chain, the pressure oil from the hydraulic pump presses the front piston side, and the piston forcibly contracts the spring. A chain tension / release operation method for a chain conveyor characterized by rapidly releasing the tension of the chain.

[0010]

Next, the operation of the present invention will be described.
When adjusting the tension state of the conveyor, when the pressure oil from the hydraulic pump is injected into the rear piston side from the rear inlet of the hydraulic cylinder that incorporates the double piston in which the two pistons extend and contract with each other, The rear piston is pushed forward to push the piston located in front of the double piston forward through a spring mounted between the two pistons, and the piston rod of the piston located in front of the double piston pushes the chain conveyor of the chain conveyor. The sprocket attached to the drive shaft on which the chain is suspended is advanced to adjust the tension of the conveyor chain. After adjusting the tension of the conveyor chain in this way, the switching valve in the hydraulic circuit is closed to maintain the tension.

Further, when the chain is caught in the tensioned state of the chain, the resistance is first received by the spring, and when the pressure oil suddenly reaches a pressure higher than the set value, The pressure oil in the piston side is automatically released by the relief valve, and adjustment is performed so that tension above a certain value is not applied. On the other hand, when releasing the tension of the chain for repairing the chain etc., the pressure oil from the hydraulic pump is injected into the front piston side and the front piston is pushed rearward, and the front piston By this, the intermediate spring is forcibly contracted to quickly release the tension of the chain.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a chain tensioning device for a chain conveyor and an operating method thereof according to the present invention will be described with reference to the drawings. FIG. 1 is a plan view of this embodiment, and FIG. 2 is an explanatory diagram of a hydraulic circuit of this embodiment. In the drawings, the same or equivalent parts as those of the conventional example are designated by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 1, in the present embodiment, a support 17 disposed on both sides of a conveyor trough 16 accommodating a scraper bar 15 of a chain conveyor 3 for transporting scraps, and a chain 20 of the chain conveyor 3. It is composed of a double piston device installed between a pair of sprockets 22 and a conveyor reduction gear storage box 23 supporting the drive shaft 21 of the sprockets 22.

The double piston device has a rear end in a cylinder 30 which is pivotally attached by a pivot pin 29 to a support 17 arranged on both sides of a conveyor trough 16 in which the scraper bar 15 is housed. A double piston is arranged so that the front and rear two pistons 31, 32 can slide in the axial direction so that they can expand and contract with each other, and a spring 3 for separating the front and rear two pistons 31, 32 from each other.
3 is installed. The piston rod of the front piston 32 is connected by a pivot pin 28 to a conveyor speed reducer storage box 23 that supports a drive shaft 21 of a pair of sprockets 22 on which the chain 20 of the chain conveyor 3 is suspended. Further, the cylinder 30 is provided with an inlet 34 for supplying pressure oil to the rear side of the rear piston 31, and conversely, an inlet 35 for supplying pressure oil is provided on the front side of the front piston 32. There is.

FIG. 2 shows a hydraulic circuit for supplying pressure oil to the double piston device. Oil in the oil tank 37 is switched by a hydraulic pump 38 to a switching valve 40 in a multi-switching valve 39.
By operating the switching valve 40, the inlet 34 for supplying pressure oil to the rear side of the piston 31 in the cylinder 30 or the inlet 35 for supplying pressure oil to the front side of the front piston 32 is pressurized. Oil is supplied. Utilizing this hydraulic circuit, pressure oil produced by the hydraulic pump 38 is supplied to the rear side of the piston 31, and the rear piston 31 is pressed forward to cause the spring 3 mounted between the two pistons.
The front piston 32 of the double piston is pushed forward via 3 and the sprocket 22 on which the chain 20 of the chain conveyor 3 is suspended is moved forward by the movement of the piston rod of the front piston 32, so that the tension state of the conveyor chain 20 is increased. adjust.

After adjusting the tension of the conveyor chain 20 in this manner, the switching valve 40 in the hydraulic circuit is closed to maintain the tension of the conveyor chain 20. When the chain is caught, the resistance is first received by the spring 33, and the rear piston 3
When the pressure oil in 1 suddenly reaches a pressure equal to or higher than the set value, the pressure oil is automatically released by the relief valve 42,
Make sure that the pressure oil in the rear piston 31 does not exceed a certain value. The switching valve 41 is used only when the conveyor chain 20 is loosened.

Therefore, according to this embodiment, in the hydraulic cylinder 30 mounted on the side portion of the chain conveyor 3, a double piston is arranged in which the two front and rear pistons 31, 32 are axially expandable and contractable. A spring 33 is installed between the two pistons so as to separate them from each other, and the piston rod of the front piston 32 of the double piston is connected to the chain tension sprocket side. There is an effect that the changeover valve 40 in the multi-changeover valve 39 can be easily and quickly operated and the chain can be adjusted safely by remote operation by hydraulic pressure.

[0018]

According to the present invention described above, a double piston which is axially expandable and contractable with each other is arranged in the cylinder, and the two pistons, front and rear, are separated from each other so as to always tension the chain. Since the spring is installed and the piston rod of the piston located in front of the double piston is connected to the chain tension sprocket side, tension and release of the chain of the chain conveyor can be operated easily and quickly by operating the switching valve of the hydraulic circuit. When the chain is caught, its resistance is first received by the spring, and the pressure oil is automatically released by the relief valve so that tension above a certain value is not applied. This has the effect of making chain adjustment work and repairs safe and quick.

[Brief description of drawings]

FIG. 1 is a plan view of the present embodiment.

FIG. 2 is an explanatory diagram of a hydraulic circuit of this embodiment.

FIG. 3 is a side view of the entire shear loader on which the present embodiment is mounted.

FIG. 4 is a plan view of a conventional example.

FIG. 5 is a plan view of a conventional example.

[Explanation of symbols]

3 chain conveyor 15 scraper bar 16 conveyor trough 17 Support 20 chains 21 Drive axis 22 sprocket 23 Conveyor reducer storage box 24 hydraulic motor 28,29 pivot pin 30 cylinders 31, 32 pistons 33 spring 34,35 Pressure oil inlet / outlet 38 hydraulic pump 39 Multi switching valve 40, 41 switching valve 42 relief valve

Front page continuation (58) Fields surveyed (Int.Cl. ⁷ , DB name) B65G 23/44 E02F 7/04

Claims (2)

(57) [Claims] 1. A chain tensioning device for a chain conveyor that conveys slips and the like by means of a scraper bar, in which a front and rear two pistons are axially expandable and contractable double pistons in a hydraulic cylinder mounted on the side of the chain conveyor. Arranged, the front and rear two pistons are separated from each other, a spring for always tensioning the chain is attached, and the piston rod of the piston located in front of the double piston is connected to the chain tensioning sprocket side, A chain tensioning device for a chain conveyor, characterized in that hydraulic pressure is introduced to a front part and a rear part of the double piston in the hydraulic cylinder. 2. A chain tensioning / releasing operation method of a chain conveyor that conveys slips and the like by a scraper bar, wherein two pistons are installed in a hydraulic cylinder having a double piston expandable / contractible via a spring, from a hydraulic pump. The rear side of the piston is pressed by the pressure oil, and the tension state of the conveyor is adjusted by the piston rod of the piston located in front of the double piston via the spring. The resistance is first received by the spring, and when the pressure oil exceeds the set value,
The pressure oil is automatically released by a relief valve so that tension above a certain value is not applied.On the other hand, when the tension of the chain is released for repairing the chain, forward pressure oil from the hydraulic pump is used. A method for tensioning / releasing a chain for a chain conveyor, characterized in that the piston side is pressed to forcibly contract the spring by the piston to quickly release the tension of the chain.