To provide a versatile and easy-to-produce link plate that can reduce frictional resistance and keep surface pressure low while maintaining a small height of a guide-side end surface, and can secure a tensile strength, and a chain. The guide-side end surface of the link plate is made up of a flat portion formed by a flat surface parallel to a line connecting centers of connection holes at leading and trailing ends, and both end surface portions on both ends in the chain longitudinal direction of the flat portion. The both end surface portions are formed to come closer to the line connecting the centers of the leading-end and trailing-end connection holes as the both end surface portions extend further from the flat portion.

A drive sprocket comprising a plurality of teeth for meshing with a drive member to transmit rotary motion, the drive member including a plurality of engagement pockets engaging the teeth of the drive sprocket, wherein each tooth has a tooth profile defined by a first side comprising a first engagement surface and an opposite second side comprising a second engagement surface, which engagement surfaces are configured such that when driven, a tooth meshes to the engagement pocket at a first contact location on the first engagement surface and also at a second contact location on the second engagement surface, wherein the first contact location is radially offset from the second contact location.

A link connecting structure includes two outer link plates and two inner link plates. An inner side of each outer link plate is formed with a concave portion between two first coupling portions at two ends thereof. A connecting surface is connected between each first coupling portion and the concave portion. The connecting surface is gradually tapered inward from each first coupling portion toward the concave portion. An outer side of each inner link plate is provided with a pair of bent portions each extending from an outermost edge of each second coupling portion toward the connecting surface. A gap is defined between each bent portion and the connecting surface. The gap is less than the minimum thickness of a narrow tooth of a chainring, thereby preventing the tooth from being jammed in the gap.

A link connecting structure includes two outer link plates and two inner link plates. An inner side of each outer link plate is formed with a concave portion between two first coupling portions at two ends thereof. A connecting surface is connected between each first coupling portion and the concave portion. The connecting surface is gradually tapered inward from each first coupling portion toward the concave portion. An outer side of each inner link plate is provided with a pair of bent portions each extending from an outermost edge of each second coupling portion toward the connecting surface. A gap is defined between each bent portion and the connecting surface. The gap is less than the minimum thickness of a narrow tooth of a chainring, thereby preventing the tooth from being jammed in the gap.

A drive chain (2a, 2b) for a chain drive comprises a plurality of chain links (10, 20) and joints (30) respectively connecting two of the chain links (10, 20) forming the drive chain (2a, 2b). The drive chain (2a, 2b) further comprises a plurality of carrier elements (40), each of said carrier elements (40) being linked to one of the chain links (10, 20) or joints (30) and supporting at least two support/engagement elements (43, 44), which are configured for supporting the drive chain (2a, 2b) and/or for engagement with an appropriate turnaround element (50; 90) for driving the drive chain (2a, 2b).

A drive chain (2a, 2b) for a chain drive comprises a plurality of chain links (10, 20) and joints (30) respectively connecting two of the chain links (10, 20) forming the drive chain (2a, 2b). The drive chain (2a, 2b) further comprises a plurality of carrier elements (40), each of said carrier elements (40) being linked to one of the chain links (10, 20) or joints (30) and supporting at least two support/engagement elements (43, 44), which are configured for supporting the drive chain (2a, 2b) and/or for engagement with an appropriate turnaround element (50; 90) for driving the drive chain (2a, 2b).

A conveyor or drive chain wear monitor includes two sensors spaced apart from one another a predetermined distance which is less than the distance between the adjacent measuring points on a chain. Two timers are provided, one of which is a chain speed timer and the other of which is the chain wear timer. The two timers are both controlled by the spaced sensors. The upstream sensor, as determined by the direction of travel of the chain, turns the speed timer on and the wear timer off. The downstream sensor turns the speed timer off and the wear timer on. Thus, when a measuring point passes the upstream sensor, the speed timer is turned on, and is not turned off again until the same measuring point passes the downstream timer. Knowing the distance between the upstream and downstream sensors, the computing module determines the speed at which the chain is moving as a function of the length of time, as determined by the speed timer, it took a measuring point on the chain to pass from the upstream sensor to the downstream sensor. When a measuring point passes the downstream sensor, it turns on the wear timer. The wear timer then remains on until a measuring point on the chain passes the upstream sensor. The wear timer will thus be turned on by a downstream measuring point, and turned off by the following upstream measuring point. Knowing the speed of the chain, the computing module can now determine the degree of wear on the chain as a function of the speed of the chain and the wear time which the wear timer is on, as compared to the baseline value for the same function when the chain is new.

Mining machines such as continuous miners and chain haulage units may include chain conveyors that are capable of deflecting laterally in order to travel through lateral turns. The chain conveyors may include flight members for pushing or urging material along a pan. The chain may be driven by one or more sprockets. In one independent aspect, a link for a chain conveyor includes a body including a first end a second end opposite the first end, a first opening proximate the first end and extending in a direction transverse to a direction of travel of the link, a second opening proximate the second end and extending in a direction transverse to the direction of travel of the link, and a relief opening extending through the link body and positioned between the first end and the second end.

Mining machines such as continuous miners and chain haulage units may include chain conveyors that are capable of deflecting laterally in order to travel through lateral turns. The chain conveyors may include flight members for pushing or urging material along a pan. The chain may be driven by one or more sprockets. In one independent aspect, a link for a chain conveyor includes a body including a first end a second end opposite the first end, a first opening proximate the first end and extending in a direction transverse to a direction of travel of the link, a second opening proximate the second end and extending in a direction transverse to the direction of travel of the link, and a relief opening extending through the link body and positioned between the first end and the second end.

A drive chain system having a chain with an alternating succession of inner chain links and outer chain links, each inner chain link having a pair of inner link plates and each outer chain link having a pair of two outer link plates contacting the inner link plates of adjacent inner chain links. A pin connects two outer link plates and two inner link plates, wherein the inner surfaces of a pair of opposite outer link plates has protrusions in the area between the adjacent inner link plates. The system has a rear cassette with a multitude of sprockets with a plurality of sprocket teeth, wherein the cassette has sprocket teeth of different tooth types, the teeth of at least one tooth type having a tip laterally offset from the centerplane.