CN105090356B - A high wear-resistant silent chain - Google Patents

Abstract

The present invention provides a kind of high abrasion silencing chain, it is made up of several link units by connecting combination, any one link units includes guide plate, flange carrier bar, different pore chain plate and rolling pin, the guide plate two ends respectively offer a guide plate pin-and-hole, the flange carrier bar two ends respectively offer a circular pin hole, and the different pore chain plate two ends respectively offer a noncircular pin hole；Flange is equipped with below two circular pin hole edges of the flange carrier bar, the flange is in semi-circular shape, patent of the present invention is as a result of above technical scheme, it is in power transmission process, so that the carrier bar of silencing chain and the bearing area of rolling pin are greatly increased, it can at least increase by 50% bearing area, simultaneously because drag chain carrier bar employs non-circular hole design, and due to the relatively common Jing Yin big many of chain in its hole, the amount that lubricating oil enters hinges is big, further increases the anti-wear performance of chain.

Description

A high wear-resistant silent chain

【Technical field】

The invention relates to a high wear-resistant silent chain.

【Background technique】

For a long time, the known silent chain has a chain plate with a planar structure, and the rolling pins are in the form of round pins or special-shaped pins. Because the chain plate holes of the silent chain are hinged with the rolling pins, and there are guide columns and non-guiding columns, the chain plate and the rolling pins in the guide columns do not rotate relative to each other, and are relatively fixed, so the wear is very small and can be ignored. And there is relative rotation in non-guiding chain plate hole and rolling pin hinge, and more than 95% of its chain length wearing and tearing all take place here. Moreover, the diameters of the chain plates of two adjacent guide rows and non-guide rows are cross-assembled, so the effective bearing surface of the chain plates and rolling pins is less than 50% of the entire chain width, and the bearing area of the sleeve roller chain reaches the entire chain width. More than 80% of the total, so the wear resistance of ordinary silent chains is worse than that of sleeve roller chains. It is also one of the main factors for bush roller chains to dominate the market so far.

However, when the silent chain has the same chain width as the sleeve roller chain, the number of chain plates increases a little, which can greatly improve the chain's load-carrying capacity and improve the reliability of the chain. At the same time, the noise of the silent chain during the transmission process is much lower than that of the sleeve roller chain.

At present, wear elongation is one of the main failure modes of silent chains, and it occupies a dominant position.

In summary, the main failure site of the silent chain is the wear and elongation between the non-guided chain plate and the rolling pin.

【Content of invention】

In order to solve the above technical problems, the purpose of the patent of the present invention is to provide a high wear-resistant silent chain, the structure mainly includes: guide plate, rolling pin, flanging chain plate and different hole chain plate. The guide plate and rolling pin are the same as the ordinary silent chain, and the inner chain plate of the ordinary silent chain is divided into a flanged chain plate and a different hole chain plate. The assembly method is that the flanging chain plate is installed in the non-guiding row, and the different-hole chain plate is installed in the guiding row. The flanging chain plate with inner hole flanging is used to increase the pressure bearing area of the chain plate and rolling pins and improve the wear resistance of the chain. The pressure bearing area of ordinary toothed chains generally does not exceed 50% of the chain width, which is the fundamental reason why the wear resistance is not as good as that of bush roller chains, because the pressure bearing surface of bush roller chain pins is 80% of the chain width. And the rolling pin bearing surface of this high wear-resistant silent chain can reach more than 90%, and its wear resistance can approach or reach the level of the sleeve roller chain. Therefore, the occasions that require high noise and wear resistance.

In order to solve the above-mentioned technical problems, the purpose of the patent of the present invention is to provide a high-wear-resistant silent chain, which is composed of several chain link units through connection and combination. plates and rolling pins,

Both ends of the guide plate are respectively provided with a guide plate pin hole, and the two ends of the flanged chain plate are respectively provided with a circular pin hole,

A special-shaped pin hole is opened at both ends of the different-hole chain plate;

Flanges are provided below the edges of the two circular pin holes of the flanged chain plate, and the flanges are in the shape of a semicircle.

The angle α between the line formed by the two ends of any flange and the center of the circular pin hole where it is located and the line connecting the centers of the two circular pin holes in the flange chain plate is 70°～90° ;

The flanging is not within the range of the entire hole, but within the range of half the hole, generally not exceeding the size of half the hole, and at the holes at both ends of the chain plate, and because the chain is deflected during transmission, the flanging There is a certain deflection angle, and the size of the angle is related to the number of teeth of the sprocket, generally 0°～20°.

The flanging chain plate has a symmetrical structure, and the two flangings on the flanging chain plate are oppositely arranged;

The thickness of the flanging on the flanging chain plate is b, the thickness of the chain plate on the flanging chain plate is c, the thickness of the different hole chain plate is d, and the relationship between them is b=0.5×d or b=d, And b=(0.2～1.2)×c, where the unit is mm;

Since the non-guiding row of the silent chain is mainly composed of flanging chain plates with inner circular holes and flanging, the space of the flanging part must be reserved for the chain plate of the guide row, and the deflection during the chain transmission power process must be guaranteed. Curved space, so the chain plate hole of the guide column must be enlarged, especially to leave space for the position where the two holes face each other. At the same time, in order to ensure the transmission of force, the outer sides of the two holes of the chain plate should be fitted with the pin shaft.

The special-shaped pin hole of the different-hole chain plate is divided into an inner circular hole and an outer flanging ring hole, wherein the inner diameter of the inner circular hole is equal to the inner diameter of the circular pin hole of the flanging chain plate,

The width e of the flanging ring hole is greater than or equal to the flanging width f on the flanging chain plate, and the central angle formed by the two ends of the flanging ring hole is 180°-240°;

The two ends of the flanging chain plate and the two ends of the different-hole chain plate are respectively connected to the guide plate through the rolling pins and the guide plate pin holes at both ends of the guide plate, and respectively form the chain transmission device with the outer contour surfaces of the two ends of the guide plate. The meshing surface of the transmission teeth, among which: the gap between the pin hole of the guide plate and the rolling pin, the circular pin hole of the flanged chain plate and the rolling pin, and the gap between the special-shaped pin hole and the rolling pin of the chain plate with different holes Cooperate.

Preferably, the flanging of the flanging link plate and the special-shaped pin hole of the different-hole link plate are in clearance fit, and the flanging of the flanging link plate is movably nested in the outer flanging ring hole of the different-hole link plate.

As a preference, any chain link unit includes N+2 guide plates, 2N flanging chain plates, N different-hole chain plates and 2 rolling pins, wherein N≥1 is a natural number;

The flanging thickness on the flanging chain plate is b, the thickness of the different hole chain plate is d, and the relationship between them is b=0.5×d;

N pairs of flanged chain plates are composed of 2N flanged chain plates. The two flanged chain plates in any pair of flanged chain plates are arranged opposite to each other. The flanging of the chain plate corresponds to the clearance fit of the special-shaped pin hole of the chain plate with different holes;

Any pair of flanged chain plates are sandwiched between two guide plates, and the rolling pins are respectively matched with the guide plate pin hole of the guide plate, the circular pin hole of the flanged chain plate and the special-shaped pin hole of the different-hole chain plate to realize rolling. The integral connection of the pin and the guide plate, the flanging chain plate and the different hole chain plate.

As a preference, any chain link unit includes 3 guide plates, N flanged chain plates, N different hole chain plates and 2 rolling pins, wherein N≥1 is a natural number;

The flanging thickness on the flanging chain plate is b, the thickness of the different hole chain plate is d, and the relationship between them is b=d;

Wherein: any one flanged chain plate is provided with a chain plate with different holes adjacent to it, and the flange of the flanged chain plate corresponds to the clearance fit with the special-shaped pin hole of the adjacent different-holed chain plate.

Preferably, equal-strength cooperation is adopted between the adjacent chain link units.

The chain with the above structure is especially suitable for chains arranged in 2×3 and 4×5. The flanging thickness of the flanging chain plate is set to 0.5 times the thickness of the chain plate, and the flanging parts are arranged in opposite directions, so that the hinged surfaces responsible for wear are changed from two to three, and its wear resistance is increased by 50%. . In the same 4×5 chain, the number of hinged surfaces responsible for wear has changed from 4 to 6, and its wear resistance has also increased by 50%. When the number of chain plates is large, the flanging chain plate should use a large flanging thickness, which is 1 times or more than the thickness of the chain plate, and when assembling, the chain plate flanging is on the same side, in order to ensure that each chain in the chain The gap between the plates is uniform, and the last chain plate of the non-guiding row is assembled with the chain plate of the ordinary silent chain. This kind of assembly can greatly increase the pressure bearing area of the chain and improve the wear resistance of the chain. The greater the number of chain plates, the greater the proportion of the pressure-bearing area, and the better the wear resistance.

Compared with prior art, the beneficial effect of the present invention:

Due to the adoption of the above technical solutions, the patent of the present invention greatly increases the pressure-bearing area of the chain plate and rolling pin of the silent chain during the power transmission process, and can increase the pressure-bearing area by at least 50%. At the same time, because the guide chain chain plate uses The non-circular special-shaped hole design is adopted, and because the hole is much larger than that of ordinary silent chains, a large amount of lubricating oil enters the hinge pair, which further improves the wear resistance of the chain.

【Description of drawings】

Fig. 1 is the front view structural representation of two adjacent chain links in the chain of 4 * 5 arrangement among the present invention;

Fig. 2-1 is the schematic diagram of the front view structure of the guide plate in the present invention;

Figure 2-2 is a schematic cross-sectional structure diagram of the guide plate in Figure 2-1;

Figure 3-1 is a schematic diagram of the front view of the flanging chain plate in the present invention;

Figure 3-2 is a schematic cross-sectional structure diagram of the flanging chain plate in Figure 3-1;

Figure 4-1 is a schematic diagram of the front view structure of the chain plate with different holes in the present invention;

Figure 4-2 is a schematic diagram of the cross-sectional structure of the different-hole chain plate in Figure 4-1;

Figure 4-3 is a partially enlarged schematic diagram of the special-shaped pin hole of the different-hole chain plate in Figure 4-1;

Figure 5-1 is one of the structural schematic diagrams of the gap between the flanging chain plate and the different hole chain plate in the present invention;

Figure 5-2 is the second schematic diagram of the clearance fit structure between the flanging chain plate and the different hole chain plate in the present invention;

Fig. 6 is the front view structural representation of a chain link in the chain of 4 * 5 arrangement among the present invention;

Fig. 7 is the front view structure diagram of a chain link in the chain of 2 * 3 arrangement among the present invention;

Drawings marked: guide plate 1, flanged chain plate 2, different hole chain plate 3, rolling pin 4, round pin hole 21A, round pin hole 21B, flange 22A, flange 22B, angle α, special-shaped pin hole 31A , Shaped pin hole 31B, inner circular hole 311, outer flanging ring hole 312, angle β.

【detailed description】

Example 1:

As shown in Figure 1, a high wear-resistant silent chain is composed of several chain link units through connection and combination. Any chain link unit includes a guide plate 1, a flanging chain plate 2, a different hole chain plate 3 and a rolling pin 4. The same strength is adopted between the adjacent chain link units; as shown in Figure 1, the chain arranged in 4×5 has three chain plates in the guide column, two of which are different-hole chain plates and the other is a common chain plate (ie, the guide plate 1), non-guiding row four flanging chain plates 2,

As shown in Figure 2-1 and Figure 2-2, a guide plate pin hole is opened at both ends of the guide plate 1,

As shown in Figure 3-1 and Figure 3-2, a circular pin hole 21A and a circular pin hole 21B are respectively opened at both ends of the flanged chain plate 2,

As shown in Figure 4-1 and Figure 4-2, a special-shaped pin hole 31A and a special-shaped pin hole 31B are opened at both ends of the different-hole chain plate 3;

The circular pin hole 21A and the circular pin hole 21B of the flanged chain plate 2 are respectively provided with a flanged edge 22A and a flanged edge 22B below the edge, and the flanged edge 22A and the flanged edge 22B are in a semi-circular shape,

As shown in Figure 3-1, the angle between the line formed by the two ends of any flange and the center of the circular pin hole where it is located and the line connecting the centers of the two circular pin holes in the flange chain plate 2 α is 70°～90°;

The flanging chain plate 2 has a symmetrical structure, and the flanging 22A on the flanging chain plate 2 is opposite to the flanging 22B;

The thickness of the flanging on the flanging chain plate 2 is b, the thickness of the chain plate on the flanging chain plate 2 is c, the thickness of the different hole chain plate 3 is d, and the mutual relationship is b=0.5×d, and b=(0.2～1.2)×c, where the unit is mm;

As shown in Figure 4-3, the special-shaped pin hole (31A or 31B) of the different-hole chain plate is divided into an inner circular hole 311 and an outer flange ring hole 312, wherein the inner diameter of the inner circular hole 311 is the same as that of the flange The inner diameters of the circular pin holes of the chain plate 2 are equal in size,

The width e of the flanging ring hole 312 is greater than or equal to the flanging width f on the flanging chain plate 2, and the central angle β formed by the two ends of the flanging ring hole 312 is 180°-240°;

The two ends of the flanging chain plate 2 and the two ends of the different-hole chain plate 3 are respectively connected to the guide plate 1 through the rolling pin 4 and the guide plate pin holes at the two ends of the guide plate 1, and are connected with the outer contours of the two ends of the guide plate 1 respectively. The surface constitutes the meshing surface of the transmission teeth of the chain transmission device, among which: between the guide pin hole of the guide plate 1 and the rolling pin 4, between the circular pin hole of the flanged chain plate 2 and the rolling pin 4, and between the hole of the different hole chain plate 3 Both the special-shaped pin hole and the rolling pin 4 are clearance fit.

The flanging of the flanging link plate 2 and the special-shaped pin hole of the different-hole link plate are in clearance fit, and the flanging of the flanging link plate 2 is movably nested in the outer flanging ring hole 312 of the different-hole link plate.

The chain plate 3 with different holes is placed in the middle of the two flanging chain plates 2 . As shown in Figure 5-1 and Figure 5-2, the hole of the different-hole chain plate 3 can accommodate the space for the flanging of the flanging chain plate 2 and the turning part of the flanging, so that the hinged surface responsible for wear is replaced by the four sides of the ordinary silent chain. increased to six, making its wear resistance also increased by 50%.

Example 2:

As shown in Figure 6, a high wear-resistant silent chain is composed of several chain link units through connection and combination. Any chain link unit includes a guide plate 1, a flanging chain plate 2, a different hole chain plate 3 and a rolling pin 4. Equal-strength cooperation is adopted between the adjacent chain link units; as shown in FIG. 6 , for a chain arranged in 4×5, the guide row has three chain plates 3 with different holes and two guide plates 1 . Three flanged chain plates 2 and one ordinary chain plate in the non-guided row,

As shown in Figure 2-1 and Figure 2-2, a guide plate pin hole is opened at both ends of the guide plate 1,

As shown in Figure 3-1 and Figure 3-2, a circular pin hole 21A and a circular pin hole 21B are respectively opened at both ends of the flanged chain plate 2,

As shown in Figure 4-1 and Figure 4-2, a special-shaped pin hole 31A and a special-shaped pin hole 31B are opened at both ends of the different-hole chain plate 3;

The circular pin hole 21A and the circular pin hole 21B of the flanged chain plate 2 are respectively provided with a flanged edge 22A and a flanged edge 22B below the edge, and the flanged edge 22A and the flanged edge 22B are in a semi-circular shape,

As shown in Figure 3-1, the angle between the line formed by the two ends of any flange and the center of the circular pin hole where it is located and the line connecting the centers of the two circular pin holes in the flange chain plate 2 α is 70°～90°;

The flanging chain plate 2 has a symmetrical structure, and the flanging 22A on the flanging chain plate 2 is opposite to the flanging 22B;

The flanging thickness on the flanging chain plate 2 is b, the chain plate thickness on the flanging chain plate 2 is c, the thickness of the different hole chain plate 3 is d, and the mutual relationship is b=d, and b= (0.2～1.2)×c, where the unit is mm;

As shown in Figure 4-3, the special-shaped pin hole (31A or 31B) of the different-hole chain plate is divided into an inner circular hole 311 and an outer flange ring hole 312, wherein the inner diameter of the inner circular hole 311 is the same as that of the flange The inner diameters of the circular pin holes of the chain plate 2 are equal in size,

The width e of the flanging ring hole 312 is greater than or equal to the flanging width f on the flanging chain plate 2, and the central angle β formed by the two ends of the flanging ring hole 312 is 180°-240°;

The two ends of the flanging chain plate 2 and the two ends of the different-hole chain plate 3 are respectively connected to the guide plate 1 through the rolling pin 4 and the guide plate pin holes at the two ends of the guide plate 1, and are connected with the outer contours of the two ends of the guide plate 1 respectively. The surface constitutes the meshing surface of the transmission teeth of the chain transmission device, among which: between the guide pin hole of the guide plate 1 and the rolling pin 4, between the circular pin hole of the flanged chain plate 2 and the rolling pin 4, and between the hole of the different hole chain plate 3 Both the special-shaped pin hole and the rolling pin 4 are clearance fit.

The flanging of the flanging link plate 2 and the special-shaped pin hole of the different-hole link plate are in clearance fit, and the flanging of the flanging link plate 2 is movably nested in the outer flanging ring hole 312 of the different-hole link plate.

The different-hole chain plate 3 is placed between the two flanged chain plates 2, as shown in Figure 5-1 and Figure 5-2, the holes of the different-holed chain plate 3 can accommodate the flanged and flanged turning parts of the flanged chain plate 2 In this way, the number of joint surfaces responsible for wear is increased from four to seven in ordinary silent chains, which improves the wear resistance by 75%.

Example 3:

As shown in Figure 7, a high-wear-resistant silent chain is composed of several chain link units through connection and combination. Any chain link unit includes a guide plate 1, a flanging chain plate 2, a different hole chain plate 3 and a rolling pin 4. Equal-strength cooperation is adopted between the adjacent chain link units; as shown in Figure 7, for a chain arranged in 2×3, the guide row has a different-hole chain plate 33 and two guide plates 11, and the non-guide row has two flanged chain plates twenty two,

As shown in Figure 2-1 and Figure 2-2, a guide plate pin hole is opened at both ends of the guide plate 1,

As shown in Figure 3-1 and Figure 3-2, a circular pin hole 21A and a circular pin hole 21B are opened at both ends of the flanged chain plate 2, and the circular pins of the flanged chain plate 2 A flange 22A and a flange 22B are respectively provided below the edge of the hole 21A and the circular pin hole 21B. The flange 22A and the flange 22B are in a semi-circular shape, and the flange chain plate 2 has a symmetrical structure, and the flange chain plate The flanging 22A on 2 is arranged opposite to the flanging 22B;

As shown in Figure 4-1 and Figure 4-2, a special-shaped pin hole 31A and a special-shaped pin hole 31B are opened at both ends of the different-hole chain plate 3;

As shown in Figure 3-1, the angle between the line formed by the two ends of any flange and the center of the circular pin hole where it is located and the line connecting the centers of the two circular pin holes in the flange chain plate 2 α is 70°～90°; the thickness of the flange on the flanged chain plate 2 is b, the thickness of the chain plate on the flanged chain plate 2 is c, the thickness of the different hole chain plate 3 is d, and the relationship between them b=0.5×d, and b=(0.2～1.2)×c, where the unit is mm;

As shown in Figure 4-3, the special-shaped pin hole of the different-hole chain plate is divided into an inner circular hole 311 and an outer flange ring hole 312, and the inner diameter of the inner circular hole 311 is the same as the circle of the flanged chain plate 2. The inner diameters of the pin holes are equal in size,

The width e of the flanging ring hole 312 is greater than or equal to the flanging width f on the flanging chain plate 2, and the central angle β formed by the two ends of the flanging ring hole 312 is 180°-240°;

The two ends of the flanging chain plate 2 and the two ends of the different-hole chain plate 3 are respectively connected to the guide plate 1 through the rolling pin 4 and the guide plate pin holes at the two ends of the guide plate 1, and are connected with the outer contours of the two ends of the guide plate 1 respectively. The surface constitutes the meshing surface of the transmission teeth of the chain transmission device, among which: between the guide pin hole of the guide plate 1 and the rolling pin 4, between the circular pin hole of the flanged chain plate 2 and the rolling pin 4, and between the hole of the different hole chain plate 3 Both the special-shaped pin hole and the rolling pin 4 are clearance fit.

The flanging of the flanging link plate 2 and the special-shaped pin hole of the different-hole link plate are in clearance fit, and the flanging of the flanging link plate 2 is movably nested in the outer flanging ring hole 312 of the different-hole link plate.

The chain plate 3 with different holes is placed in the middle of the two flanging chain plates 2 . As shown in Figure 5-1 and Figure 5-2, the special-shaped pin hole of the different-hole chain plate 3 can accommodate the space for the flanging of the flanging chain plate 2 and the turning part of the flanging, so that the hinge surface responsible for wear is replaced by the ordinary silent chain. Two, increased to three, increased its wear resistance by 50%.

The above-mentioned embodiment is an illustration of the present invention, not a limitation of the present invention, and any scheme after simple transformation of the present invention belongs to the protection scope of the present invention.

Claims (5)

1. a kind of high abrasion silencing chain, is made up of several link units by connecting combination, it is characterised in that：Any one Link units include guide plate, flange carrier bar, different pore chain plate and rolling pin,

The guide plate two ends respectively offer a guide plate pin-and-hole, and the flange carrier bar two ends respectively offer a circular pin hole,

The different pore chain plate two ends respectively offer a noncircular pin hole；

Flange is equipped with below two circular pin hole edges of the flange carrier bar, the flange is in semi-circular shape,

Two in the line and the flange carrier bar that the two ends edge of any of which flange and the circular pin hole center of circle at place are formed Angle is in 70 °~90 ° between the circle center line connecting of circular pin hole；

The flange carrier bar is oppositely arranged in two flange on symmetrical structure, and flange carrier bar；

Flange thickness on the flange carrier bar is that the thickness of link plates on b, flange carrier bar is c, and the thickness of different pore chain plate is d, phase Relation is b=0.5 × d or b=d between mutually, and b=(0.2~1.2) × c, wherein unit are mm；

The noncircular pin hole of the different pore chain plate is divided into inner circular hole and flanging annular distance, and wherein the internal diameter size in inner circular hole is with turning over The internal diameter of the circular pin hole of side chain plate is equal in magnitude,

The flange width f that the width e of flanging annular distance is more than or equal on flange carrier bar, and the two ends edge institute shape of flanging annular distance Into central angle be 180 °~240 °；

The flange carrier bar two ends and different pore chain plate two ends respectively by the guide plate pin-and-hole at rolling pin and the guide plate two ends realize with The connection of guide plate and the respectively field of conjugate action with the driving cog of the outer surface composition chain gearing at the two ends of the guide plate, its In：Between the guide plate pin-and-hole and rolling pin of guide plate, between the circular pin hole of flange carrier bar and rolling pin, the noncircular pin hole of different pore chain plate with It is that gap coordinates between rolling pin.

2. a kind of high abrasion silencing chain according to claim 1, it is characterised in that the flange of the flange carrier bar with Gap coordinates between the noncircular pin hole of different pore chain plate, and the flange of flange carrier bar is nested in the flanging annular distance of different pore chain plate.

3. a kind of high abrasion silencing chain according to claim 2, it is characterised in that any one link units is wrapped Include N+2 blocks guide plate, 2N block flange carrier bar, the different pore chain plate of N blocks and 2 rolling pin, the wherein natural number of N >=1；

Flange thickness on the flange carrier bar is that b, the thickness of different pore chain plate are d, and relation is b=0.5 × d each other；2N N is constituted in block flange carrier bar to flange carrier bar, two flange carrier bars in any pair of flange carrier bar are oppositely arranged, in the middle of both 1 block of different pore chain plate is folded with, the flange of two flange carrier bars corresponds to the noncircular pin hole gap cooperation with the different pore chain plate respectively；

Any pair of flange carrier bar is folded between two pieces of guide plates, rolling pin guide plate pin-and-hole respectively with guide plate, flange carrier bar The noncircular pin hole gap of circular pin hole and different pore chain plate coordinates, and realizes that rolling pin and guide plate, flange carrier bar, different pore chain plate integrally connect Connect.

4. a kind of high abrasion silencing chain according to claim 2, it is characterised in that any one link units is wrapped Include 3 pieces of guide plates, N block flange carrier bar, the different pore chain plate of N blocks and 2 rolling pin, the wherein natural number of N >=1；

Flange thickness on the flange carrier bar is that b, the thickness of different pore chain plate are d, and relation is b=d each other；Wherein：Appoint One block of flange carrier bar of meaning is both provided with the different pore chain plate of adjacent thereto one block, flange correspondence and the adjacent different hole of the flange carrier bar The noncircular pin hole gap of carrier bar coordinates.

5. a kind of high abrasion silencing chain according to claim 3 or 4, it is characterised in that adopted between adjacent link unit Coordinated with equal strength.