4results about How to "Close fast" patented technology

Provided is a flow path control device which includes a fourth on-off valve 304 for opening or closing a fourth communication path through which oil flows from a jack chamber to a reservoir chamber, a third on-off valve 303 which controls the opening and closing of the fourth on-off valve 304 by transiting between a first state in which the fourth on-off valve 304 is moved to a position where the fourth communication path is closed and a second state in which the fourth on-off valve 304 is moved to a position where the fourth communication path is opened, and a push rod 316 which includes a push rod main body 316a of which one end is pressed and moved to the other side and the other end causes the third on-off valve 303 to transition from the first state to the second state and a washer 700 which protrudes radially outward of the push rod main body 316a from an outer peripheral surface of the push rod main body 316a so as to receive pressure of oil flowing from the jack chamber to the reservoir chamber.

The present invention provides a construction method for a locally deepened open-cut shaft, which relates to the technical field of tunnel construction and includes: first constructing a diaphragm wall, excavating to a first preset elevation to construct the first ring beam, then excavating down to a second preset elevation, and constructing the second ring beam and the first side wall between the first ring beam and the second ring beam; taking the bottom of the second ring beam as the excavation surface, constructing the shaft foundation and the locally deepened foundation, arranging a vertical support member between the top surface of the locally deepened foundation and the bottom surface of the second ring beam, and constructing the remaining side walls and ring beams from bottom to top relying on the vertical support member and the first side wall until the top of the shaft is closed, and finally constructing the second side wall between the top surface of the locally deepened foundation and the bottom surface of the second ring beam. This method improves the closing speed and construction safety of the main structure of the locally deepened open-cut shaft. By constructing the ring beam as a permanent support structure, the demolition process of the temporary waist beam is eliminated, and the problem of asynchronous construction of the left and right side walls in the traditional top-down method is solved.

This utility model discloses a novel in-lens shutter structure, comprising a lower fixed base and an upper cover plate. A middle partition plate, a first upper blade located on the upper side of the middle partition plate, and a first lower blade located on the lower side of the middle partition plate are installed within the blade receiving cavity. A blade driving assembly is installed on the lower fixed base, including a crank. The first upper blade and the first lower blade rotate synchronously in opposite directions under the drive of the crank. A second upper blade, stacked with the first upper blade, is installed on the upper side of the middle partition plate, and a second lower blade, stacked with the first lower blade, is installed on the lower side of the middle partition plate. The first upper blade and the second upper blade are staggered, and the first lower blade and the second lower blade are also staggered. The second upper blade and the second lower blade rotate synchronously in opposite directions under the drive of the crank. This utility model has the advantages of novel structural design and fast closing speed, and can effectively reduce the distortion of object shape when shooting high-speed moving objects or rapid panning.