JPH0747406B2 - Conveyor belt synchronous tension device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION << Industrial Application Field >> The present invention relates to a belt conveyor, and tension for the conveyor belt can be adjusted in synchronization by synchronizing the tensions on the left and right side bands in the width direction. Regarding the device.

<< Prior Art >> Conventionally, as a tensioning device for applying tension to a conveyor belt in a belt conveyor, as shown in FIG.
The driven shaft b is erected between the left and right frames c and c so as to be movable in the longitudinal direction (transport direction) with respect to the drive shaft a, and the driven shaft b is connected to the respective ends and the frames c and c. It is known that the tension springs d, d stretched between the two pull the springs in a direction away from the drive shaft a,
In the figure, e is a conveyor belt, f is a drive roller, and g
Indicates a driven roller fitted to the driven shaft b so as to be rotatable.

However, when using the above device, the left and right belts in the width direction of the conveyor belt e are separately and independently tensioned by the left and right tension springs d and d. The non-uniform expansion and contraction of the driven shaft b causes the driven shaft b to incline as shown by the chain double-dashed line in the figure, which causes the parallel state with the drive shaft a to collapse, and as a result, the running conveyor belt e It is known that undesired phenomena such as so-called meandering and waviness occur, which makes it impossible to smoothly convey an object to be conveyed. Therefore, in order to eliminate the above-mentioned defect,
Like No. 216, by providing a bearing support body to which a spring force is applied to both end portions of the driven shaft, and by engaging a protrusion provided on the frame side in a groove provided in the bearing support body, , The bearing support is moved by being guided by the ridges, thereby allowing the driven shaft to move in the length direction of the conveyor belt while always keeping the driven shaft in parallel with the drive shaft, We are trying to eliminate the meandering and waviness of the conveyor belt.

<Problems to be Solved by the Invention> However, even in the case of the above proposal, when the tension of the belt conveyor is to be adjusted, the spring force is adjusted by rotating the nut. When
If only the tension adjustment operation at one end of the driven shaft is performed, the protrusion is engaged with the groove as described above, the driven shaft cannot be moved, and the tension adjustment operation at both ends is performed almost at the same time. If this is not done, the movement cannot be performed.Furthermore, after such a troublesome adjustment operation, the spring force at each end must be adjusted to the same strength and the tension at both ends must be synchronized. I have to.

Further, in the case of the above proposal, since the driven shaft is always movable only in a state orthogonal to the longitudinal direction of the conveyor belt, unbalanced elongation or contraction occurs in each side belt portion in the width direction of the conveyor belt. In such a case, the conveyor belt cannot contact the driven roller in a uniform state over the entire width, and as a result, a meandering phenomenon occurs, but such an unintentional state is corrected. It becomes impossible to do.

The present invention has been made in view of the above problems of the above-described conventional device, and is configured such that the pinions fixed to both ends of the driven shaft so as to be disengageable and the racks provided on the frame side are engaged with each other. By adding, by always maintaining the parallel state of the drive shaft and the driven shaft in response to uneven expansion and contraction of the conveyor belt, not only to make it difficult for the conveyor belt to meander, etc.
If the conveyor belt is adjusted only at one end of the driven shaft with respect to its tension, the driven shaft is moved in synchronization with the other end, and the operability is the first object.

Further, in the present invention, even in the case of the above-mentioned undesired meandering, the fixed state of the pinion is released, and the required one end of the driven shaft is displaced in the longitudinal direction of the conveyor belt. Allow the shaft to be in an oblique state, not orthogonal to the traveling direction of the conveyor belt,
As a result, it is possible to secure a uniform contact state between the conveyor belt and the driven roller and deal with the meandering phenomenon.
Is the purpose of.

<< Means for Solving the Problem >> The present invention, in order to achieve the above-mentioned object, a driven roller around which a conveyor belt is wound is rotatably supported,
Both ends are equipped with driven shafts that are movably installed in the length direction of the conveyor belt by being inserted into the left and right frames, and both ends of the driven shaft are slidable in the left and right frames. Is supported and is biased rearward by the elastic force of the adjustable spring so that each driven adjusting rod is rotatably connected to urge the driven shaft away from the drive shaft. At the same time, each of the driven shafts is provided with a meshing feed means composed of a pinion fixed so that it can be disengaged, and a rack fixed to each of the left and right frames by meshing with the pinion. An object of the present invention is to provide a synchronous tension device for a conveyor belt characterized by:

<Operation> The nut is tightened while compressing the spring by rotating only the nut screwed to the adjusting screw on the desired one side in the tightening direction, and the elastic force of the spring causes the adjusting screw to move. When the driven shaft is retracted, the one end of the driven shaft is pulled in a direction away from the drive shaft in the length direction of the conveyor belt, and at this time, the rack and the feeding motion of the meshing feeding means by the pinion cause the other of the driven shaft to move. Since the end also synchronizes with the same distance and is screwed forward, the driven shaft moves backward while maintaining a state perpendicular to the traveling direction of the conveyor belt, which gives normal tension to the conveyor belt. To do. Contrary to the above, by only loosening the nut on one side, the spring expands and the elastic force acting on the adjusting screw is reduced, so the adjusting screw moves forward and not only on the one side. In synchronization with the adjusting screw on the other side, the respective pinions in both mesh feed means advance along the rack,
The driven shaft advances in a direction perpendicular to the traveling direction of the conveyor belt, and the distance between the driven shaft and the drive shaft becomes small, so that the tension of the conveyor belt is released and the conveyor belt is bent.

Therefore, by operating the nut on one side, both ends of the driven shaft can be moved and adjusted to the desired position in synchronization without any effort, and the conveyor belt can be adjusted without adjusting the spring strength. A value of tension will be applied, and the left and right mesh feed means by the pinion and rack will prevent unintentional inclination of the driven shaft, and even if the conveyor belt stretches or contracts, it will always be parallel to the drive shaft. It does not cause meandering or waviness.

Furthermore, with respect to the pinion fixed to one end of the driven shaft, the pinion idles when the one end of the driven shaft is laterally moved in the longitudinal direction of the conveyor belt after the fixing is released and the pinion is freely rotatable. If one end part is displaced and the pinion is fixed in this state, the driven shaft can be tilted, not parallel to the drive shaft.
Therefore, by doing so, even when unbalanced expansion or contraction occurs in the belt on both sides in the width direction of the conveyor belt, the driven shaft is inclined as described above by aligning it with the unbalanced expansion or contraction of the conveyor belt. The driven shaft can be brought into contact with the driven shaft in a uniform state, whereby it is possible to take measures against the above-mentioned meandering of the conveyor belt.

Example An example of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan view showing a belt conveyor partially cut away,
FIG. 2 shows an enlarged sectional view taken along the line II-II of FIG. 1, in which the left and right (upper and lower in FIG. 1) frames 1, 1 ′ are
The drive shaft 2 is formed integrally by arranging channel steels in parallel and has a front end (right side in FIG. 1) with a bearing (not shown) interposed.
Is rotatably mounted on the drive shaft 2, and the drive roller 3 is fixed between the left and right frames 1, 1 ′ so as to rotate integrally with the drive shaft 2. Is
The pulley 4 is fixed because power is transmitted by a drive source (not shown) and a winding transmission mechanism (not shown).

Webs 1a near the rear ends of the left and right frames 1, 1 ',
1a 'is provided with elongated holes 5 and 5 which are long and penetrating in the front-rear direction (horizontal direction in FIG. 1), and the webs 1a and 1a at the portions where the elongated holes 5 and 5 are provided. ', Thick plates 6, 6 are fixed to the outer surface thereof by a plurality of bar nuts 7 ...

As clearly shown in FIG. 3, each of the plates 6 and 6 has a long hole 8 which is long in the front-rear direction, and the long holes 5 of the frames 1 and 1 '.
It is pierced with the required width and length in line with No. 5.

Bushings 10 and 10 'are rotatably mounted on the driven shaft 9 in the vicinity of both ends thereof.
As shown in the drawing, circular cutouts 10a, 10a 'are formed symmetrically on the outer peripheral surface, and these circular cutouts 10a, 10a' slide on the upper and lower surfaces 8a, 8b of the elongated holes 8, 8 of the plate 6, respectively. As a surface, the bushes 10 and 10 ′ have the long holes 8 and 8 ′ so as to be movable laterally.
As a result, the driven shaft 9 is elongated in the longitudinal direction (right and left direction in FIG. 1) perpendicular to the axial direction.
Are erected on the left and right frames 1, 1'to be movable within the effective length range.

A driven roller 11 is rotatably supported by the driven shaft 9 between the left and right frames 1, 1 ′. That is, as shown in FIG. 2, cases 12 and 12 are fitted and fixed to both ends of a conventional roller 11 having a cylindrical shape.
The driven roller 9 is externally mounted on the driven shaft 9 through the bearings 13 and 13 which are internally fitted to the driven shaft 9. By fixing the set collar 14 to the driven shaft 9 with a set screw 15, the driven roller 11 is rotatable on the driven shaft 9. Is pivotally supported.

Further, the driven shaft 9 is shown by arrows hh 'in FIGS. 1 and 3 between the protruding ends of the driven shaft 9 protruding from the left and right frames 1, 1'and between the plates 6, 6. Interlocking feeding means 16, 16 for moving and adjusting in the front-back direction are formed.

That is, the left and right mesh feed means 16, 16 are
The pinion 16a, which can be fixed by the set screw 17, and the rack 16b, which is on the outer surface of the plate 6 and is parallel to the elongated hole 8 and fixed to the lower portion thereof by the bar nut 18, are meshed with each other. And the pinion 16a, 1
The driven shaft 9 is configured to be movable in the front-rear direction by the action of the 6a in the meshed state with the racks 16b and 16b.

Here, both pinions 16a, 1 of the left and right mesh feed means 16, 16
6a are formed with the same pitch, while both racks 16b, 1
6b has the same pitch.

Further, plates 19 and 19 are fixed to the webs 1a and 1a 'at the front end portions of the left and right frames 1 and 1'in a perpendicular state by welding or the like, and the plates 19 and 19 are attached to the adjusting screw punch mounting plate 20, As shown in FIG. 4, 20 is fixed with bar nuts 21 ..., and symmetrically projected outward. As shown in FIG. 3, a bush 23 is fitted into the through holes 22 and 22 formed in the plates 20 and 20, and an adjusting screw 24 is slidably inserted in the front-rear direction.

The base ends of both the adjusting screw rods 24, 24 are rotatably connected to the respective end portions of the driven shaft 9 by a universal joint 25, etc., while the male screw portion 24a at the tip end is provided with a spring receiver 26 and a washer. The adjusting nut 28 ... is screwed through 27 and the plate 19
The compression springs 29, 29 are mounted between the spring receiver 26 and the spring receiver 26 on the tip end side of the adjusting screw rods 24, 24, and the driven shaft 9 is mounted by the compression springs 29, 29 via the adjusting screw rods 24, 24. It is urged forward as indicated by arrow h in FIGS. 1 and 3.

1 and 2, reference numeral 30 shows a conveyor belt wound around the driving roller 3 and the driven roller 11.

In the case of the conveyor belt synchronous tension device configured as described above, the compression spring 29 is compressed by only tightening one of the nuts 28, 28 screwed to the left and right adjusting screw rods 24, 24. , Its elastic force acts so as to move the adjusting screw 24 forward (to the left in FIG. 1), so that the adjusting screw 24 slides forward and pulls the end of the driven shaft 9 forward. At this time, since the pinion 16a in the mesh feeding means 16 moves forward while meshing with the rack 16b, even if the pinion 16a and the rack 1 are at the other end of the driven shaft 9.
Drive shaft 2 is moved forward in synchronization with the engagement of 6b.
The axial distances between and increase at the left and right ends in a uniform manner and increase, so that a uniform tension is applied to the conveyor belt 30 by the driven shaft 9.

Next, when the nut 28 on the arbitrary one side is rotated in a direction to be loosened, the compression spring 29 expands, and the elastic force in the axial direction decreases, whereby the adjusting screw rods 24, 24 retreat. The pinion 16a in the mesh feeding means 16 is the rack 1
The driven shaft 9 rolls rearward while meshing with the drive shaft 6b. At this time, even if the driven shaft 9 is at the other end of the driven shaft 9, the driven shaft 9 is moved rearward synchronously by the engagement of the pinion 16a and the rack 16b, and the drive shaft 2 Therefore, the distance between the axes becomes uniformly small, and the conveyor belt 30 bends.

Further, when the synchronous tension device is used, when the belt on one side in the width direction of the conveyor belt expands and the belt on the other side contracts, the driven shaft 9 is orthogonal to the traveling direction of the conveyor belt. In this state, the conveyor belt does not come into uniform contact with the driven roller 11 on the driven shaft 9 over the entire length, so that the meandering phenomenon occurs on the conveyor belt.

Therefore, in such a case, the pinion 16 of the driven shaft 9 is located on the side of the one side band where the conveyor belt 30 has contracted.
After setting a to an idle state by turning the set screw 17,
One end of the driven shaft 9 is moved laterally toward the drive shaft 2 side,
Therefore, if the set screw 17 is tightened, the driven shaft 9 can be changed from the parallel state to the drive shaft 2 to the oblique state.
The meandering phenomenon can be eliminated by placing the conveyor belt 30 in a uniform contact state over the entire length of the driven roller 11.

<< Advantages of the Invention >> Since the present invention is configured as described above, the driven shaft moves forward or backward against the spring force and the spring force against expansion and contraction of the conveyor belt. In addition to being able to cope with this, the driven shaft is fed in the front-rear direction in synchronization by both meshing feed means by the left and right pinions and racks, and therefore the driven shaft is simply tilted by the mesh feed means. Not only does this mean that the conveyor belt is always kept parallel to the drive shaft, which not only makes it difficult for the conveyor belt to meander, wavy, etc. Thus, the left and right tensions in the width direction of the conveyor belt can be reliably synchronized and adjusted, and the left and right mesh feed means are simultaneously operated. The difficulty can be eliminated.

Further, according to the present invention, since the pinion of the driven shaft can be released and fixed and can be rotated at any time in the free state, only one end of the driven shaft in the longitudinal direction of the conveyor belt in this state. If the driven shaft can be tilted with respect to the drive shaft after it has been moved, it can be tilted with respect to the drive shaft. However, the meandering can be avoided by aligning with the conveyor belt.

[Brief description of drawings]

FIG. 1 is a partially cutaway plan view of an embodiment showing a synchronous tension device for a conveyor belt according to the present invention, FIG. 2 is an enlarged sectional view taken along the line II-II in FIG. 1, and FIG. FIG. 4 is an enlarged front view showing a main part of the embodiment, FIG. 4 is a side view showing a mounting portion of an adjusting screw on a frame of the embodiment, and FIG. 5 is a bush of a driven shaft and an elongated hole of a plate in the embodiment. And FIG. 6 is a plan view showing a synchronous tension device for a conveyor belt in a conventional belt conveyor. 1 …… frame 1 ′ …… frame 2 …… driving shaft 9 …… driven shaft 11 …… driven roller 16 …… interlocking feed means 16a …… pinion 16b …… rack 24 …… adjusting screw rod 29 …… spring

Claims (1)

[Claims] 1. A driven roller around which a conveyor belt is wound is rotatably supported, and both ends thereof are erected so as to be movable in the length direction of the conveyor belt by being inserted into left and right frames. Each of the adjusting screw rods is provided with a driven shaft, is slidably supported on the left and right frames at both ends of the driven shaft, and is biased rearward by the elastic force of an adjustable spring. Rotatably connecting the driven shaft to the drive shaft in a direction away from the drive shaft, and a pinion fixed to both ends of the driven shaft so that the pinion can be disengaged. A synchronous tension device for a conveyor belt, characterized in that each frame is provided with an interlocking feeding means constituted by a rack fixedly mounted on the frame.