34results about How to "Uniform adsorption capacity" patented technology

The invention relates to a clamp, and specifically discloses a vacuum adsorption clamp. The vacuum adsorption clamp comprises a fixed plate and a workpiece adsorption block arranged on the fixed plate, wherein the upper surface of the workpiece adsorption block is used for adsorbing a sheet-shaped workpiece; a plurality of first air holes arranged in the form of an annular structure are formed ina position close to the edge of the outer side of the upper surface of the workpiece adsorption block, on the upper surface, the first air holes are blind holes, a plurality of second air holes penetrating through the upper surface and the lower surface of the workpiece adsorption block are formed in the inner side of the annular structure encircled by the plurality of first air holes, and each first air hole communicates with the adjacent second air hole through a ventilation groove; and a sealing cavity communicating with the second air holes is formed in the fixed plate, and air extractionholes communicating with the sealing cavity are formed in the outer side of the fixed plate. According to the vacuum adsorption clamp, the uniform overall adsorption force of the sheet-shaped workpiece can be achieved, the generation of volcanic vents, ring marks and jig marks is avoided, and the edge of the sheet-shaped workpiece can further be prevented from being tilted, so that the rigidity ofthe edge of the vacuum adsorption clamp is guaranteed.

The invention provides a technique with which it is possible to suppress the generation of dust at the time of attracting and detaching an object to be attracted by reducing attraction force on a surface that comes into contact with the object to be attracted, and to control the attraction force of an attraction device so as to be uniform. This attraction device comprises: a main body part 50 including, in a dielectric, a pair of attraction electrodes 11, 12 of opposite polarities for attracting and holding a substrate 10; and electroconductive films 51 each arranged in a section on the attraction side of the main body part 50 with respect to the pair of attraction electrodes 11, 12, the electroconductive films being arranged so as to extend across an anode 11a and a cathode 11b of the paired attraction electrode 11 and an anode 12a and a cathode 12b of the paired attraction electrode 12, respectively.

The invention discloses a casting sand box comprising a sand box bottom, a sand box wall and an upper air exhaust lifting and pressing lever, wherein a sand box body consisting of the sand box bottom, the sand box wall and the upper air exhaust lifting and pressing lever is halfpace-shaped; the upper air exhaust lifting and pressing lever consists of transverse air levers and vertical air levers of an air duct, which are transversely and vertically arranged inside and are communicated with an upper air exhaust pipe; each transverse air lever comprises a main transverse air lever and a secondary transverse air lever; each secondary transverse air level is arranged at the outer side of the main transverse air lever; each vertical air lever comprises a main vertical air lever and secondary vertical air levers; and the secondary vertical air levers are uniformly arranged at the both sides of each main vertical air lever. The area at the upper part of the casting sand box provided by the invention is increased, so that the quantity of sands is increased; and when the sands are rammed, the gravity of the sands generates an inward horizontal component under the effect of the wall of the sand box, so that the sands are filled in a lateral hole of a casting, and the quantity of defective goods can be greatly reduced. The casting sand box provided by the invention has more uniform adsorption force on molding sands by upper air exhaust lifting and pressing lever, is conductive to improving the working efficiency, and can be used for greatly reducing the crush rate, and ensuring the product quality.

The invention relates to the field of SMT equipment application, in particular to a clamping and fastening device. A clamping mechanism for SMT screen plate measurement comprises a fixed seat, a locating hole penetrating through the thickness of the fixed seat is formed in the fixed seat, and the clamping mechanism for SMT screen plate measurement further comprises a two-dimensional freedom degree adjusting mechanism. The two-dimensional freedom degree adjusting mechanism is arranged below the fixed seat, and is used for adjusting lift-and-right inclination and front-and-back inclination of the fixed seat. Due to the fact that the mentioned technical scheme is adopted, through an accurate two-dimensional angle adjusting function, the clamping mechanism for SMT screen plate measurement can adjust the working surface of the fixed seat to be perpendicular to the vertical moving direction of a vertical type measuring head conveniently, and guarantee full attachment of a screen plate and the working surface of the clamping mechanism in a measuring process, and repeated measurement accuracy of the screen plate is guaranteed to be in + / - 1 micron.