GB1568416A

GB1568416A - Belt conveyor having a device for converting articles laterally from it

Info

Publication number: GB1568416A
Application number: GB2983777A
Authority: GB
Original assignee: Sandvik Conveyor GmbH
Current assignee: Sandvik Conveyor GmbH
Priority date: 1977-07-15
Filing date: 1977-07-15
Publication date: 1980-05-29

Description

(54) A BELT CONVEYOR HAVING A DEVICE FOR DIVERTING ARTICLES LATERALLY FROM IT (71) We, SANDVIK CONVEYOR G.m.b.H, a German limited Liability company, of Salierstrasse 38, 7012 Fellbach, Federal Republic of Germany, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The present invention relates to a belt conveyor having a device for diverting articles laterally from it, such as may be used in, for example, an article sorting machine.

An article sorting machine is known, which, for sorting articles depending on destinations in a truck terminal or in a shipment section of a factory, or for sorting various parts depending on size, shape or the likes as one step of the manufacturing process in various factories, uses a belt conveyor. Articles transported by the belt conveyor are sorted and pushed out to one side of the conveyor by operating a plurality of diverters arranged along one side of the belt conveyor. A portion of such known article sorting machine is shown in Figure 1 in a plan view.

In Figure 1, the reference numeral 1 designates a steel belt conveyor, and the articles 2a, 2b as loaded on the conveyor are transported in the direction of the arrow 3.

The reference numeral 4 designates a diverter of which one end is connected to a pivot 5 for being pivoted thereby between a retracted position shown by a solid line and an extended position shown by a dot and dash line, wherein the diverter is extended over the conveyor 1. A plurality of such diverters are arranged along the conveyor 1.

Each diverter 4 is pivoted into the extended position when a predetermined article arrives. Thus the article is pushed out by the diverter aside the conveyor and received by a chute 6. If the articles are to be sorted according to destination, for instance, the diverters are allocated in such way that for example the first diverter pushes out articles to be sent to the Bristol area, the second diverter those for the Liverpoool area, the third diverter those for the Glasgow area and so on for the remaining diverters. Thus, the first diverter is operated only when an article which is to be shipped to the Bristol area arrives. How the articles are identified and a particular diverter is operated, does not constitute a part of the present invention.

In such an article sorting machine, it is necessary to maintain the longitudinal distance between the articles on the belt 1 at at least a minimum value for proper sorting.

Now it is assumed that the article 2a is located close to the left-hand edge of the belt as viewed in the moving direction of the conveyor 1 and the succeeding article 2b is located close to the right-hand edge. In this longitudinal distance, it is required that the diverter 4 be operated with a delay after the rear end of the article 2a has passed the forward end of the diverter 4. The distance corresponding to this delay is designated 1l.

When the diverter 4 is pivoted to the extended position, the forward end of the diverter 4 moves backwardly as viewed in the moving direction of the belt conveyor as shown by the arc 7, and the longitudinal distance of such backward movement is shown by 12 in Figure 1. Furthermore, a certain time is required for the diverter to pivot from its retracted position to the extended position, and during this time the article 2b will move a corresponding distance. This distance is indicated by 13. Thus, in order to enable the diverter to push out the article 2b after the article 2a has passed, it is necessary that the longitudinal distance L is at least 11 + 12+ 13.

The sorting capacity of the article sorting machine (number of articles which can be sorted per unit time) is determined by the minimum distance L between the articles on the belt. In other words, the sorting capacity will be increased if the minimum distance L could be decreased.

Thus, an object of the present invention is to improve the sorting capacity of an article sorting machine by decreasing the backward movement distance 12 or arranging the divertion 4 so that its forward end is beyond the distance 12 in the conveyor movement direction.

Referring to Figure 2, which is a plan view of a diverter over a belt conveyor showing two methods of hingeing the diverter, in order most effectively to use a diverter arm 4, it has been proposed heretofore to locate the pivot adjacent to one side edge 8 of the belt at the rearmost end of the diverter arm i.e. at point A.

According to this invention we provide a belt conveyor having a device for diverting articles laterally from the conveyor, the device including: a diverter arm swingable about an axis normal to the surface of the belt between an inoperative position in which it extends along one edge of the belt and an operative position in which it extends over the belt for diverting an article from the belt, with its free end extending substantially to the other edge of the belt; a pivot shaft connected to the diverter arm and disposed above or below the belt; and drive means connected to the pivot shaft for swinging the diverter arm about the said axis between the inoperative and operative positions;; the location of said axis being such that when a triangle is drawn, having as its apices a first point located on the said one edge of the belt. a second point where an arc of a radius equal to the length of the diverter arm and drawn about the first point crosses the said one edge forward of the first point, and a third point where the arc crosses the other edge of the belt, the said axis is located at the side of a bisector of the triangle passing through the first point, which side is closer to the said other edge, and such that the diverter arm is swingable between inoperative and operative positions through an angle of less than ninety degrees.

Thus. as is shown by way of example in Figure 2, a circle or an arc of circle 9 is drawn about a first point A with a radius which is equal to the full length of the diverter arm.

The point B at which the circle or arc 9 crosses the side edge 8 of the belt forward of the first point A as viewed in the moving direction 3 of the belt is referred to as the second point, and the point C at which the circle or arc 9 crosses the other side edge 10 of the belt is referred to as the third point. Then, a triangle is drawn having the first, second and third points A, B and C as its apexes, and further a bisector 11 is drawn passing through the first point A of the triangle, B, C. The axis of a pivot shaft 5 is located to one side of the bisector 11, which is closer to the other side edge 10 of the belt, and the diverter arm 4 is connected to the pivot shaft 5 by arm means 12. The arm means 12 is fixed to the diverter arm 4.Thus, the diverter arm 4 when driven will be pivoted into the extended position shown by the dot and dash line, the forward end of the diverter arm having described a path 13, and in the extended position, the forward end of the diverter arm 4 is positioned forwardly by a distance 14 from the position it occupied in the retracted positon. Thus, taking into consideration the backward movement distance 12 in the prior apparatus, the minimum distance L which has to be maintained between the articles on the belt could be decreased by a distance 12 + 14, and a corresponding improvement of the sorting capacity of the article sorting machine would be obtainable.

Now, what must be considered is the position of the axis of the pivot shaft 5. As has been described, the axis must be at that side of the bisector 11 of the triangle A, B, C, passing through the first point A, which is closer to the belt edge 10.

If the axis of the pivot shaft 5 is located at the side of the bisector 11, which is closer to the one side edge 8 of the belt, the distance of backward movement of the forward end of the diverter arm becomes larger than 12.

However, if the axis of the pivot shaft 5 is located at the side of the bisector 11 which is closer to the belt edge 10, the distance of backward movement becomes smaller than 12, and even the forward end of the diverter 4 may be moved forwardly beyond the distance 12, as shown in Figure 2. It is not always necessary that the axis of the pivot shaft 5 be located within the width of the belt, but it may be located outside the belt width beyond the belt edge 10.

However, it is not sufficient that the axis of the pivot shaft 5 be located at the side of the bisector 11, which is closer to the belt edge 10. It is also necessary that the location of the axis of the pivot shaft 5 should allow the pivotal movement of the diverter arm from its retracted position into the extended position with an angle of the pivotal movement which is less than ninety degrees. Otherwise the inclination of the diverter arm in its retracted position will be reversed, and proper operation will not be obtainable.

This means that the angle a of the pivotal movement of the arm means 12 is less than ninety degrees. More particularly, the angle p (a) included between the line connecting the position E of the axis of the pivot shaft 5 and the point D at which the forward end of the diverter arm 4 crosses the belt edge 10 in the extended position and the line connecting the second point B and the said pointE, is less than ninety degrees.

In the above, the principle of the invention has been described. Embodiments of the invention will now be described by way of example and with reference to the remaining figures of the drawings, in which: Figure 3 is a plan of a first embodiment of the invention; Figure 4 is a sectional side elevation of the apparatus of Figure 3 taken along the line IV-IV in Figure 3; Figure 5 is a plan of a second embodiment of the invention; Figure 6 is a corresponding sectional side elevation of the second embodiment; and Figure 7 is a plan of a third embodiment of the invention.

(In these Figures the same reference numeral indicates the same or like element. Thus, the reference numeral 1 designates a steel belt conveyor, 4 a diverter arm, 5 a pivot shaft, 12 arm means, A the first point, B the second point, C the third point, 11 the bisector, 16 a frame, 18 a shaft, 19 an arm, 20 an electric motor, 30 a shaft, 32 an arm, and a an angle of pivotal movement).

First, referring to the embodiment as shown in Figures 3 and 4, the pivot shaft 5 is located below the steel belt 14 of the belt conveyor 1. It will be easily noted that the location of the axis 15 of the pivot shaft 5 satisfies the conditions as above described.

Namely, the angle of the pivotal movement is less than ninety degreees, and it is apparent that the axis 15 is located at the side of the bisector of the triangle passing through the point A, which is closer to the belt edge 10 because the axis 15 is located actually at the side of the line interconnecting the points A and C, which is closer to the belt edge 10.

The pivot shaft 5 is rotatably supported by means of a bearing 17 which is fixedly supported by a frame 16. In this embodiment, the arm means 12 interconnecting the pivot shaft 5 and the diverter arm 4 comprises a shaft 18 fixed to the diverter 4 by suitable means such as welding or press fitting and depending downwardly from the diverter arm 4, and an arm 19 having its one end fixedly connected to the shaft and the other end fixedly connected to the pivot shaft 5 by similar means. The drive means for pivoting the diverter arm 4 comprises an electric motor 20 having a speed reduction means and fixedly supported by the frame 16, and means 21 for converting the rotational movement of the motor 20 into a reciprocal pivotal movement of a predetermined angular degree a of the pivot shaft 5.This conversion means 21 comprises a circular disc 22 fixed to the reduced speed output shaft of the electric motor 20, a pin 23 mounted on the peripheral portion of the dioc 22, a bearing 24 fitted on the pin 23, an arm 25 having its one end fixedly connected to the bearing 24, another bearing 26 fixedly connected to the other end of the arm 25, another pin 27 fitted into the bearing 26, and another arm 28 having its one end loosely fitted on the pin 27 and the other end connected to the arm 19.

Thus, when the circular disc 22 is rotated in the direction of the arrow 29 by means of the electric motor 20, the pivot shaft 5 will be reciprocally pivoted for the angle a through the arms 25 and 28. Since the pivot shaft 5 is fixed relative to the diverter arm 4 through the arm 19 and the shaft 18, the diverter arm 4 is also pivoted between its retracted position shown by a solid line and the extended position shown by a dot and dash line when the pivot shaft 5 is pivotally moved.

In the second embodiment, as shown in Figures 5 and 6, the pivot shaft 5 is located above the steel belt 14 and supported by the frame 16. It will be easily noted that the position or location of the axis 15 of the pivot shaft 5 satisfies the two conditions as above described. In this embodiment, the arm means 12 interconnecting the pivot shaft 5 and the diverter arm 4 comprises a shaft 30 fixedly connected to the diveter arm 4 and extending upwardly therefrom, and an arm 32 having its one end fixedly connected to the shaft 30 by a bolt 31 and the other end loosely fitted on the pivot shaft 5.

The drive means for driving the diverter arm 4 is similar to that of the embodiment of Figures 3 and 4, but is different therefrom in that the arm 28 is fixedly connected to the shaft 30 extending upwardly from the diverter arm 4, and in that the shaft 30 is moved to and fro by the arm 28.

A feature of the embodiment of Figures 5 and 6 is that the pivot shaft 5 is located in alignment with the rear end portion of the diverter arm 4 as viewed in the transverse direction of the belt 14 and that the arm 32 is extended transversely of the belt 14. According to such arrangement, when the diverter arm 4 is povited from its retracted position into the extended position, the shaft 30 is not moved away from the belt edge 8 so that the rear end of the diverter arm 4 does not move away from the belt 14.

Now referring to Figure 7, a preferred interconnection of the pivot shaft 5 and the diverter arm 4 by means of the arm means 12 in the embodiment of Figures 3 and 4 is shown. Namely, the arm 19 of the arm means 12 interconnects the pivot shaft 5 and the diverter arm 4 in such a way that the arm 19 is inclined rearwardly by an angle of sty/2 from a transverse line 33 passing through the axis 15 of the pivot shaft 5 when the diverter arm 4 is in its retracted position, wherein a is an angle of the pivotal movement of the arm 19.

According to this arrangement, the shaft 30 could be located adjacent to the side edge 8 of the belt 14 and the distance through which the shaft 30 is moved away from the belt edge 8 is small. This arrangement is particularly effective, when applied to the embodiment of Figures 3 and 4, to avoid contact between the shaft 18 and the belt while ensuring the most effective use of the diverter.

WHAT WE CLAIM IS: 1. A belt conveyor having a device for diverting articles laterally from the conveyor, the device including: a diverter arm swingable about an axis normal to the surface of the belt between an inoperative position in which it extends along one edge of the belt and an operative position in which it extends over the belt for diverting an article from the belt, with its free end extending substantially to the other edge of the belt; a pivot shaft connected to the diverter arm and disposed above or below the belt; and drive means connected to the pivot shaft for swinging the diverter arm about the said axis between the inoperative and operative positions;; the location of the said axis being such that when a triangle is drawn, having as its apices a first point located on the said one edge of the belt, a second point where an arc of a radius equal to the length of the diverter arm and drawn about the first point crosses the said one edge forward of the first point, and a third point where the arc crosses the other edge of the belt, the said axis is located at the side of a bisector of the triangle passing through the first point, which side is closer to the said other edge, and such that the diverter arm is swingable between inoperative positions through an angle of less than ninety degrees.

2. A conveyor as claimed in Claim 1 wherein the pivot shaft and the diverter arm are interconnected by arm means fixedly secured to the pivot shaft and the diverter arm, and said drive means for driving the diverter comprises an electric motor and means for converting the rotative movement of the electric motor into a reciprocating movement of the pivot shaft over a predetermined angle.

3. A conveyor as claimed in Claim 1 wherein the pivot shaft and the diverter arm are interconnected by arm means fixedly secured to the diverter, and said drive means comprises an electric motor and there being means connected between the electric motor and the diverter arm for converting the rotative movement of the electric motor into a reciprocating movement of the diverter arm over a predetermined angle.

4. A conveyor as claimed in Claim 1 wherein the pivot shaft is located in alignment with the rear end portion of the diverter arm as viewed in the transverse direction of the belt, arm means interconnecting the pivot shaft and the diverter arm, which arm means in the retracted position of the diverter arm extends transversely of the belt and is connected to the rear end portion of the diverter arm.

5. A conveyor as claimed in Claim 2 wherein the pivot shaft extends downwardly below the belt from said arm means.

6. A conveyor as claimed in Claim 2 wherein the pivot shaft extends upwardly above the belt from said arm means.

7. A conveyor as claimed in Claims 5 and 6 wherein said arm of said arm means interconnecting the pivot shaft and the diverter arm, is connected to the pivot shaft and to the diverter arm in such way that the arm of said arm means is inclined rearwardly by an angle of a/ 2 from a transverse line passing through the axis of the pivot shaft when the diverter arm is in its retracted position, wherein a is the angle of the pivotal movement of the arm of said arm means.

8. A belt conveyor constructed and arranged substantially as herein described and shown in Figures 2 to 7 of the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. of Figures 3 and 4, to avoid contact between the shaft 18 and the belt while ensuring the most effective use of the diverter. WHAT WE CLAIM IS:

1. A belt conveyor having a device for diverting articles laterally from the conveyor, the device including: a diverter arm swingable about an axis normal to the surface of the belt between an inoperative position in which it extends along one edge of the belt and an operative position in which it extends over the belt for diverting an article from the belt, with its free end extending substantially to the other edge of the belt; a pivot shaft connected to the diverter arm and disposed above or below the belt; and drive means connected to the pivot shaft for swinging the diverter arm about the said axis between the inoperative and operative positions;; the location of the said axis being such that when a triangle is drawn, having as its apices a first point located on the said one edge of the belt, a second point where an arc of a radius equal to the length of the diverter arm and drawn about the first point crosses the said one edge forward of the first point, and a third point where the arc crosses the other edge of the belt, the said axis is located at the side of a bisector of the triangle passing through the first point, which side is closer to the said other edge, and such that the diverter arm is swingable between inoperative positions through an angle of less than ninety degrees.