Portal frame

About: Portal frame is a research topic. Over the lifetime, 1778 publications have been published within this topic receiving 7210 citations.

Portal type automatic stainless steel mirror polishing machine

Abstract: The utility model discloses a portal type automatic stainless steel mirror polishing machine. A portal beam is arranged at the upper end of a portal frame, a vertical direction driving motor and a horizontal front-and-back driving motor are arranged at the two ends of the portal beam respectively, a horizontal transversely-arranged lead screw is arranged in a mounting base, a manual translational fine-adjustment handle wheel used for controlling the horizontal transversely-arranged lead screw is arranged at one end of the mounting base, the two ends of the horizontal transversely-arranged lead screw are connected with the vertical direction driving motor and the horizontal front-and-back driving motor respectively, a polishing device is installed on the mounting base, the polishing device comprises a spindle motor, a spindle bearing pedestal and a grinding disk sequentially from top to bottom, an air cylinder is installed on the spindle bearing pedestal, and an electronic console is arranged beside the portal frame. The portal type automatic stainless steel mirror polishing machine is simple in structure and reasonable in design, the structure and the characteristics of a numerical-control portal machine tool are fully and ingeniously used for reference, adjustment at three spatial dimension degrees can be smoothly achieved, and the portal type automatic stainless steel mirror polishing machine is good in polishing quality and wide in polishing range and has high practical value.

Stability and Optimization of the Portal Frame with Rigid Members and Flexible Joints

Abstract: This paper considers a portal frame with rigid members and flexible joints. The stability and postbuckling characteristics are derived analytically. The optimum frame to raise a load to a given height is trapezoidal in shape, with only the top two joints heavily strengthened.

Roller system of fork truck portal frame

Abstract: The utility model discloses a roller system of a fork truck portal frame. The upper part of an outer portal frame is provided with an outer portal frame separation roller which comes into contact with an inner portal frame or a middle portal frame in a lifting process to realize sliding and rolling, the lower part of the inner portal frame is provided with an inner portal frame composite roller which comes into contact with the outer portal frame or the middle portal frame in the lifting process to realize sliding and rolling, a side roller of the outer portal frame separation roller is arranged outside channel steel and can be very conveniently designed, installed and adjusted, and a main roller is arranged inside the channel steel and basically not affected by a portal frame beam and can be arranged at will under the condition that the normal use of the roller is not affected; and the composite roller is arranged at the lower part of the inner portal frame, the upper and lower positions of the composite roller can be arranged according to actual needs, and a fork arm carrier roller can be flexibly arranged according to the characteristics of a two-stage portal frame and a three-stage portal frame so as to achieve the purposes of flexible design and convenience in installation and maintenance.

Automatic lifting type portal frame control method based on geomagnetism detection

Abstract: The invention discloses an automatic lifting type portal frame control method based on geomagnetism detection. The automatic lifting type portal frame control method comprises the steps of 1, acquiring speed information and vehicle type information of a vehicle which is about to pass through a lifting type portal frame before a lifting rod goes down through a geomagnetism detector; 2, judging whether the vehicle type of the vehicle belongs to a limited vehicle type; 3, obtaining time T1 and time T2; 4, judging whether T1 is longer than or equal to T2, and if yes, executing the step 5; 5, performing a yellow warning control strategy and executing the step 7, and if T1 is not longer than or equal to T2, executing the step 6; 6, performing a red warning control strategy and executing the step 1; and 7, sending a signal to control the lifting rod to go down to a set position, thus terminating the control. According to the automatic lifting type portal frame control method based on the geomagnetism detection, the potential safety hazard of collision accidents caused by a fact that a large-size ultrahigh vehicle drives into a conventional lifting type portal frame within the time period when the lifting rod goes down in the prior art is well eliminated; the shortcomings of poor safety and low automation degree in a lifting process of the lifting type portal frame in the prior art are overcome.