A tensioning arrangement for a scraper for a conveyor belt, the tensioning arrangement comprising a hydraulic assembly that acts on the scraper to maintain a portion of the scraper in operative contact with the conveyor belt, the hydraulic assembly configured such that weight applied to a portion of the hydraulic assembly effects application of pressure on fluid contained within the hydraulic assembly.

A tensioning arrangement for a scraper for a conveyor belt, the tensioning arrangement comprising a hydraulic assembly that acts on the scraper to maintain a portion of the scraper in operative contact with the conveyor belt, the hydraulic assembly configured such that weight applied to a portion of the hydraulic assembly effects application of pressure on fluid contained within the hydraulic assembly.

A potential energy store has a hydraulic cylinder in which a piston for storing energy in the form of potential energy of the piston is arranged. A position of the piston relative to the earth's surface can be varied. A pump pumps hydraulic fluid via lines into the hydraulic cylinder such that the piston is raised. A generator converts hydraulic energy of hydraulic fluid, which is displaced out of the hydraulic cylinder as the piston falls, into electricity. A seal arrangement is at least partially arranged between the hydraulic cylinder and the piston. The seal arrangement has a sealing section with a flexible support structure for absorbing the acting forces. The support structure may be coated on one or both sides with a layer which is impervious to fluid and which seals against the passage of fluid or may be impregnated with a solidified material which is impervious to fluid.

A system for storing potential energy includes a hydraulic cylinder, a mass to be lifted, and a sealing ring at the edge of the mass to be lifted. The mass to be lifted is a solid rock mass in the form of a cut-out solid rock. The hydraulic cylinder is formed by the cavity between surrounding rocks and the cut-out solid rock. The cavity is sealed with respect to the surrounding rocks by the sealing ring. A method for producing such a system is also provided.

A system for storing energy includes a body and a shaft having walls defining an internal volume for containing a fluid, a seal member disposed between the body and the walls of the shaft, and a fluid passage in fluid communication with the shaft. The body is disposed within the internal volume of the shaft for movement with gravity from a first elevation position to a second elevation position within the internal volume of the shaft. The seal member divides the internal volume into a first portion located below the body and a second portion located above the body. The fluid passage communicates fluid with the first portion of the interior volume of the shaft. The system further includes a pump/turbine operatively coupled with the fluid passage to drive a motor/generator to generate electricity upon movement of the body from the first elevation position to the second elevation position.

There is provided a pressure applying device capable of applying pressure to a working object with a substantially constant force through a compact structure. The pressure applying device includes a pressure accumulating portion; a piston including a small-diameter portion inserted into a cylinder portion on a pressure accumulating portion side, and a large-diameter portion disposed close to a working object W; and a tubular body extending from the large-diameter portion to the cylinder portion. A lubricating fluid is held inside the tubular body.

There is provided a pressure applying device capable of applying pressure to a working object with a substantially constant force through a compact structure. The pressure applying device includes a pressure accumulating portion; a piston including a small-diameter portion inserted into a cylinder portion on a pressure accumulating portion side, and a large-diameter portion disposed close to a working object W; and a tubular body extending from the large-diameter portion to the cylinder portion. A lubricating fluid is held inside the tubular body.

A device for isothermal compression, constant-pressure power generation and physical energy storage includes an air storage tank, a weight, a piston and a piston rod. An inner cavity of the air storage tank is divided into first to third chambers by first and second heat conducting baffles. The piston is arranged in the second chamber. The piston rod has a lower end connected with the piston and an upper end connected with the weight. First and second elastic sealing belts are arranged in the first and third chambers, respectively. The first chamber includes a first water injection port and a first water outlet above the first elastic sealing belt, and the third chamber includes a second water injection port and a second water outlet above the second elastic sealing belt. A bottom of the air storage tank includes an air injection port and a compressed air outlet.