GB1602016A

GB1602016A - Scraper for a scraper conveyor

Info

Publication number: GB1602016A
Application number: GB3304980A
Authority: GB
Original assignee: BECKER PRUENTE GmbH; STAHLHAMMER BOMMERN Gebr SCHNEIDER
Current assignee: BECKER PRUENTE GmbH; STAHLHAMMER BOMMERN Gebr SCHNEIDER
Priority date: 1977-04-20
Filing date: 1978-04-19
Publication date: 1981-11-04
Also published as: DE2717448A1; DE2717448C3; DE2717448B2; BE866070A

Description

(54) IMPROVED SCRAPER FOR A SCRAPER CONVEYOR (71) We, BECKER-PRijNTE GmbH and STAHLHAMMER BOMMERN Gebr SCHNEIDER, both Bodies Corporate of the Federal Republic of Germany, of August Becker-Str. 10, D-4354 Datteln and Rodenborn 28, D-5810 Witten-Bommern, respectively, 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::- This invention relates to an elongate scraper for attachment to at least one chain of a scraper conveyor, the scraper conveyor being of the kind comprising an upper part and a lower part detachably connected together so as to interlock with each other, the upper and lower parts having a pair of confronting surfaces each of which surfaces defines, in a central region thereof, four channels extending from one to the longitudinal side of the scraper and separated from each other by bars, the channels and bars in the upper part being arranged to confront, respectively, the channels and bars in the lower part to provide first and second pairs of confronting channels which are separated by a first pair of confronting bars and which are designed to embraces spaced apart portions of one horizontal link of one chain of a double central chain, and third and fourth pairs of confronting channels which are separated by a second pair of confronting bars and which are designed to embrace spaced apart portions of one horizontal link of the other chain of the double central chain, the second and third pairs of confronting channels being separated by a third pair of confronting ones of said bars which are positioned substantially midway between the ends of the scraper between the said first and second confronting pairs of said bars.

Throughout this specification references to "horizontal" or "vertical" in relation to a scraper or scraper chain are intended to relate to the disposition of these parts when forming part of a horizontally disposed chain or scraper conveyor.

Scraper conveyors are increasingly being driven by central chains (i.e. chains attached to central regions of the scrapers) instead of by spaced-apart chains attached to end regions of the scrapers. There are two types of central chains, namely double central chains which operate with two chains arranged parallel to each other in the conveying direction of the scraper conveyor on either side of the centre of the conveyor, and single central chains which run in the centre of the conveyor. Conveying with single central chains has the advantage that the chain belt runs more easily in horizontal and spatial curves. On the other hand, although the double central chain is more difficult to bend round such curves, it has the advantage of being relatively stronger and more reliable in operation.

The known kind of two-part scraper has advantages compared with a onepiece scraper since a strap, used with one-piece scrapers for attaching horizontal links of a chain to the scraper, is not required for clamping the links to the scraper. By not employing such straps it is possible to avoid weakening the central region of the scraper which, in use of the scraper, is particularly highly loaded. Moreover, two part scrapers can be used for single or double central chains.

Dividing the chain beds in a known twopart scraper of the kind described, has the advantage that so-called long-length chains can be used in the scraper conveyor. These long-length chains make superfluous the need for chain bolts which are necessary for short-length chains but which are costly and are frequently the reason for broken chains.

With a scraper of the kind described intended for attachment to double central chains, the aim has been in the past to construct the chain bed intended to hold a link lying horizontally in such a way that the most extensive possible support of the link is ensured. In particular, provision is made for the link to be encompassed right round by the said channels. In addition. the channels are made of such a length that they are shaped at the ends corresponding to the shoulders of the rounded parts of the clamped link which is lying horizontally.

and in the ends of the channels there are also rounded out recesses to support each vertical link connected to the clamped link.

On one hand, this construction of the chain bed does not take into account the relatively wide tolerances which arise both in the dimensions of different chain links and in the dimensions of the parts of the chain bed in the scraper, which is generally forged, which are caused by this manufacturing method. The extensive support of the chain link on the confines of the chain bed as intended in the design is not achieved at all. On the other hand. the designed extensive adaptation of the chain bcd to the clamped link has the disadvantage that other scrapers are needed in order to operate the chain conveyor with a single central chain.

This state of affairs is particularly inconvenient underground, since frequently during the installation of a conveyor of this kind the installation conditions change, so that, for example, the ability to traverse curves is required, and correspondingly the transition from double central chains to single central chains is necessary, or vice versa for short gradients on the conveying path. In such cases all the scrapers or the whole chain belt have or has to be replaced.

The present invention aims to provide an elongate scraper suitable for attachment to either double central chains or a single central chain of a scraper conveyor, the scraper retaining the basic advantages described hereinbefore.

According to the present invention an elongate scraper of the kind referred to is characterized in that the said second and third pairs of channels are dimensioned and arranged to embrace spaced apart portions of a horizontal link of a single central chain to attach the single central chain to the scraper, and in that each of the said bars of the lower part is equipped with supporting means on their end faces on opposite sides of the scraper for supporting rounded portions of vertical links of a chain connected to a horizontal link of the chain embraced in the scraper.

With the invention, the horizontal, clamped links are actually intended always to rest with only part of their periphery on the channel walls. This results from the fact that the distance between the shanks of a single central chain is greater than the distance between the shanks of the links of a double chain, due to the comparatively larger diameter of the chain steel. For example, central chains are made with 30 mm diameter chain steel and double central chains are made with a 26 mm diameter chain steel.

With the invention, the dimensions can be selected in the designs so that the clamping of the thicker links of a single central chain is effected over the complete circumference of 360 , but only a fraction of the links of double central chains, e.g. around 90 , are enclosed. On the other hand the actual clamping effect which is obtained with the known scrapers, bearing in mind the tolerances totalling +1.8 to 2.0 mm, is also considerably less than shown on the designs, so that as a result the reduction in clamping effect in the peripheral direction which must obviously be taken into account when the invention is put into effect, is not as great compared withthe prior art as would appear in theory.

For this reason, according to the invention the enclosure of the horizontal link which is to be clamped is reduced in the axial direction by shortening the channels.

This is compensated by increasing the support on the supporting sections on the end faces for the vertical links connected on either side of the clamped horizontal link.

The combined effect of these measures means that the distinct advantage is obtained that the scraper is equally wellsuited for operation with double central chains or with a single central chain.

Accordingly, scraper conveyors can be adapted to give greater ability for traversing curves, or greater security, as required.

without the scrapers or even the whole chain belt having to be changed over. The ability to remain in place affords corresponding advantages.

Suitably each channel has a length less than the width of the scraper adjacent each channel, each channel having a length substantially the same as the length of the straight shank of a link of the double central chain it is designed to embrace, and each supporting means having a recess to partially enclose the vertical link it is adapted to support.

Conveniently each of the bars of the upper part has a recess formed in each of its end faces for supporting the rounded portions of vertical links of a chain connected to a horizontal link of the chain embraced in the scraper.

The invention will now be described, by way of example, with particular reference to the accompanying drawings, in which: Figure 1 shows a perspective view of a lower part of a scraper according to the invention Figure 2 shows a perspective view of an upper part attachable to the lower part shown in Figure 1, Figure 3 is a perspective view from below of the two parts shown in Figures 1 and 2 in an assembled state, the assembled scraper being shown attached to a central chain, the bolts having been omitted, Figure 4 shows the scraper of Figure 3 attached to a double central chain, Figure 5 is a sectional view showing the relationship in a scraper according to the invention between the radial enclosure of chain links of central chains and double central chains, and Figure 6 is a plan of the lower part shown in Figure 1.

Figures 3 and 4 show an elongate scraper consisting of a lower part (see Figure 1), generally designated 102, and an upper part (see Figure 2), generally designated 133, which are detachably connected together so as to interlock with each other.

The lower part 102 has a lower face 101 which is adapted to the conditions in a scraper conveyor trough (not shown) and is therefore substantially pre-determined. The lower part 102 has an upper face which runs along a dividing surface of the scraper and has a central region extending over the middle of the scraper and generally designated 103 and two adjoining end regions 104 and 105 which curve upwards.

The scraper is constructed symmetrically along a mid-plane extending vertically and parallel to the elongate direction of the scraper, so that it will be sufficient only to describe in detail the side face which can be seen in Figure 1.

End sections 107 and 108 of the lower part are arranged on either side of a central part, given the general designation 106, and form a structural unit with the central part 106.

The end sections 107 and 108 have upper surfaces facing the dividing surface and which are provided with grooved sections 109 and 110, respectively which interlock with bar sections 139 and 140, respectively, formed in the upper part (shown in Figure 2) of the scraper to prevent separation of the upper and lower parts during use of the scraper. The central part 106 has a chain bed portion adapted to receive and locate the links of a chain for attaching the chain of a conveyor to the scraper. For operation with a single central chain (as shown in Figure 3), a central bar 111 is used which projects into the space inside a horizontal link of the central chain. This bar 111 is formed on a bar 112 which forms the central part 106. Channels 113 and 114 are formed in the upper face of the central part 106 on either side of the central bar 111.These channels have a continuously constant cross-section and are also identical to each other. They serve both to house the straight shanks of the horizontal central chain link which has been placed over the bar 111, and also to hold the links, also lying horizontally, of a double central chain if such a double central chain is to be employed (see Figure 4). If a double central chain is employed, the links of the chain are placed over bars 115 and 116, one straight shank of each link being located in channel 114 (115) and the other straight shank of each link being located in a channel 117 (or 118) positioned outwardly of, but adjacent to, the bar 115 (116). On each side of the bar 112 which forms the central part 106 there are supporting sections, of which, however, only the supporting sections arranged on one side of the bar 112 can be seen in Figure 1.For this reason, reference will now be made to the schematic illustration shown in Figure 6.

As can be seen in Figure 6, one supporting section is located on each of the two end faces of the central bar 111, and these supporting sections bear the reference numerals 119 and 120. Similarly, on the end faces of the bars 116 and 115 there are supporting sections 121, 122 and 123, 124, respectively. Each supporting section also has a recess 125 (supporting sections 121124) or 126 (supporting sections 119, 120).

Since the recesses in the supporting sections which are associated with the bars 115 or 116 are identical, they only need be differentiated from the recesses 126 in the supporting sections 119 and 120 which are associated with the central bar 111. There the recesses 126 are in fact narrower, because the supporting sections 119 and 120 are narrower in the longitudinal direction of the scraper than the supporting sections 121-124. For the rest, each of the recesses is hollowed out as is indicated in the supporting section 121 with the reference numeral 129.

As can be seen also in Figure 6, the two channels 113 and 114 arranged on either side of the central bar 111 are wider than the channels 117 and 118 which lie on the outside. This is due to the relatively wide chain separation which is shown at 130 for the single central chain (chain steel diameter 30 mm) and at 131 for the double central chain (chain steel diameter 26 mm).

The upper part of the scraper shown in Figures 3 and 4 is shown in Figure 2 and has been given the general designation 133. The upper part is shorter than the lower part. In addition, the scraper upper part 133 is shown in Figure 2 lying on its upper face so that its face which confronts the upper face of the lower part can be seen more clearly.

The surfaces 135 and 136 (corresponding to the surfaces 127 and 128 in the lower part 102) and the surfaces 137 or 138 in the upper part 133 (corresponding to the surfaces 104 and 105 in the lower part 102) are equipped with the previously referred to bar sections 139 and 140. As previously mentioned these bar sections fit in the groove sections 109 and 110 in the lower part 102 and ensure the interlocking of the lower part 102 with the upper part 133. The upper part has recesses 141 or 142 which pass from top to bottom which are completed by recesses 143, 144 (Figure 6) in the lower part and are used for bolts for bolting together the upper and lower parts. These bolts, which are not shown, are located outside the central zone 106 in which the lower part is narrowed, so that the recesses cannot further weaken the scraper at a susceptible point.

The upper part also has a chain bed portion which corresponds to the chain bed portion of the lower part described above, the corresponding parts of the two chain bed portions being designated with an apostrophe to simplify the illustration in Figure 2. Thus, first, second, third and fourth pairs of channels are defined by confronting channels 117-117', 114--114', 113-113' and 118-118', respectively.

Furthermore, the first and second pairs of channels 117-117' and 11A 114' are separated by a first pair of confronting bars 115-115', the third and fourth pairs of channels 113-113' and 118-118' are separated by a second pair of confronting bars 116--116' and the second and third pairs of channels llP-114' and 113-113' are separated by a third pair of confronting bars 111-111'. Corresponding to the construction of the lower part, the upper part has several hollowed out recesses 145, 146 (Figure 3) on each longitudinal side, shaped to fit the rounded parts of the links, for use with double central chains.These recesses act on the vertical links 157-159 which adjoin either side of the clamped horizontal links 155 and 156.

According to the construction examples shown, not only can uniform lower parts be used for both types of operation, but also uniform upper parts. This means that when the type of drive is changed only the chains need be changed.

When using double central chains (Figure 4) the hollowed-out recess 152 in the upper part, which is naturally provided on both sides, is not used. It is used to suDport the links 148, 149 of a single central chain with operation as shown in Figure 3.

In Figure 4 only the recesses appertaining to the links 157 and 158 can be seen, due to the chosen method of illustrating.

Figure 5 shows schematically the enclosing of the links with the different types of operation, as determined by the design. It will be seen that the enclosure of the horizontal links 155 and 156 of the double central chains 153 and 154 is designed to be 360" for the outer shank of links 155 and 156, whilst the enclosure of the inner shank amounts to approximately 90".

The enclosure of the horizontal link 150 of the central chain amounts to 360" for each link-shank in the construction example shown.

In each of the elongate scrapers hereinbefore described the confronting surfaces of the upper and lower parts meet at interfaces which extend from one to the other side of the scraper and do not emerge at a bottom face of the scraper. Thus only the lower part is subjected to wear when the scraper is moved along the bottom of a trough of a chain conveyor.

Other aspects of a scraper for attachment to a scraper conveyor are described and claimed in the complete specification of our co-pending Patent Application No. 15392/78 serial No 1602015 from which the present application has been divided.

WHAT WE CLAIM IS: 1. An elongate scraper for attachment to at least one chain of a scraper conveyor, the scraper comprising an upper part and a lower part detachably connected together so as to interlock with each other, the upper and lower parts having a pair of confronting surfaces each of which surfaces defines, in a central region thereof, four channels extending from one to the other longitudinal side of the scraper and separated from each other by bars, the channels and bars in the upper part being arranged to confront, respectively, the channels and bars in the lower part to provide first and second pairs of confronting channels which are separated by a first pair of confronting bars and which are designed to embrace spaced apart portions of one horizontal link of one chain of a double central chain, and third and fourth pairs of confronting channels which are separated by a second pair of confronting bars and which are designed to embrace spaced apart portions of one horizontal link of the other chain of the double central chain, the second and third pairs of confronting channels being separated by a third pair of confronting ones of said bars which are positioned substantially midway between the ends of the scraper between the said first and second confronting pairs of said bars, characterised in that the said second and third pairs of channels are dimensioned and arranged to embrace spaced apart portions of a horizontal link of a single central chain to attach the single central chain to the scraper, and in that each of the said bars of the lower part is equipped with supporting means on their end faces on opposite sides of the scraper for supporting rounded portions of vertical links of a chain connected to a horizontal link of the chain embraced in the scraper.

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

Claims

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

139 and 140. As previously mentioned these bar sections fit in the groove sections 109 and 110 in the lower part 102 and ensure the interlocking of the lower part 102 with the upper part 133. The upper part has recesses 141 or 142 which pass from top to bottom which are completed by recesses 143, 144 (Figure 6) in the lower part and are used for bolts for bolting together the upper and lower parts. These bolts, which are not shown, are located outside the central zone 106 in which the lower part is narrowed, so that the recesses cannot further weaken the scraper at a susceptible point.

The upper part also has a chain bed portion which corresponds to the chain bed portion of the lower part described above, the corresponding parts of the two chain bed portions being designated with an apostrophe to simplify the illustration in Figure 2. Thus, first, second, third and fourth pairs of channels are defined by confronting channels 117-117', 114--114', 113-113' and 118-118', respectively.

Furthermore, the first and second pairs of channels 117-117' and 11A 114' are separated by a first pair of confronting bars 115-115', the third and fourth pairs of channels 113-113' and 118-118' are separated by a second pair of confronting bars 116--116' and the second and third pairs of channels llP-114' and 113-113' are separated by a third pair of confronting bars 111-111'. Corresponding to the construction of the lower part, the upper part has several hollowed out recesses 145, 146 (Figure 3) on each longitudinal side, shaped to fit the rounded parts of the links, for use with double central chains.These recesses act on the vertical links 157-159 which adjoin either side of the clamped horizontal links 155 and 156.

According to the construction examples shown, not only can uniform lower parts be used for both types of operation, but also uniform upper parts. This means that when the type of drive is changed only the chains need be changed.

When using double central chains (Figure 4) the hollowed-out recess 152 in the upper part, which is naturally provided on both sides, is not used. It is used to suDport the links 148, 149 of a single central chain with operation as shown in Figure 3.

In Figure 4 only the recesses appertaining to the links 157 and 158 can be seen, due to the chosen method of illustrating.

Figure 5 shows schematically the enclosing of the links with the different types of operation, as determined by the design. It will be seen that the enclosure of the horizontal links 155 and 156 of the double central chains 153 and 154 is designed to be 360" for the outer shank of links 155 and 156, whilst the enclosure of the inner shank amounts to approximately 90".

The enclosure of the horizontal link 150 of the central chain amounts to 360" for each link-shank in the construction example shown.

In each of the elongate scrapers hereinbefore described the confronting surfaces of the upper and lower parts meet at interfaces which extend from one to the other side of the scraper and do not emerge at a bottom face of the scraper. Thus only the lower part is subjected to wear when the scraper is moved along the bottom of a trough of a chain conveyor.

Other aspects of a scraper for attachment to a scraper conveyor are described and claimed in the complete specification of our co-pending Patent Application No. 15392/78 serial No 1602015 from which the present application has been divided.

WHAT WE CLAIM IS: 1. An elongate scraper for attachment to at least one chain of a scraper conveyor, the scraper comprising an upper part and a lower part detachably connected together so as to interlock with each other, the upper and lower parts having a pair of confronting surfaces each of which surfaces defines, in a central region thereof, four channels extending from one to the other longitudinal side of the scraper and separated from each other by bars, the channels and bars in the upper part being arranged to confront, respectively, the channels and bars in the lower part to provide first and second pairs of confronting channels which are separated by a first pair of confronting bars and which are designed to embrace spaced apart portions of one horizontal link of one chain of a double central chain, and third and fourth pairs of confronting channels which are separated by a second pair of confronting bars and which are designed to embrace spaced apart portions of one horizontal link of the other chain of the double central chain, the second and third pairs of confronting channels being separated by a third pair of confronting ones of said bars which are positioned substantially midway between the ends of the scraper between the said first and second confronting pairs of said bars, characterised in that the said second and third pairs of channels are dimensioned and arranged to embrace spaced apart portions of a horizontal link of a single central chain to attach the single central chain to the scraper, and in that each of the said bars of the lower part is equipped with supporting means on their end faces on opposite sides of the scraper for supporting rounded portions of vertical links of a chain connected to a horizontal link of the chain embraced in the scraper.
2. A scraper according to claim 1, in

which each of the channels has a length less than the width of the scraper adjacent each channel, each channel having a length substantially the same as the length of the straight shank of a link of the double central chain it is designed to embrace, and each supporting means having a recess for partially enclosing the vertical link it is adapted to support.
3. A scraper according to claim 1 or 2, in which each of the bars of the upper part has a recess formed in each of its end faces for supporting the rounded portions of vertical links of a chain connected to a horizontal link of the chain embraced in the scraper.
4. A scraper according to any of the preceding claims, in which each of the second and third pairs of channels is wider in the elongate direction of the scraper than each of the first and fourth pairs of channels, and in which the supporting means on the central bar of the lower part are narrower than the supporting means on the other two bars of the lower part.
5. An elongate scraper for attachment to at least one chain of a scraper conveyor, the scraper being substantially as hereinbefore described with reference to, and as illustrated in, Figures 1, 2, 3 and 6, or Figures 1,2,3 and 6 as modified by Figure 4 and/or Figure 5 of the accompanying drawings.
6. A scraper conveyor incorporating scrapers as claimed in any preceding claim.