Pumping mechanism and pump truck provided with same

Abstract

The invention discloses a pumping mechanism and a pump truck provided with the same. The pumping mechanism comprises a first oil cylinder, a second oil cylinder, a hydraulic pump, a first push head, a second push head, a first sensor, a second sensor, a first position sensor and a second position sensor. The first sensor is provided with a plurality of first sensing points arrayed at intervals in the axial direction of a first piston rod, and the second sensor is provided with a plurality of second sensing points arrayed at intervals in the axial direction of a second piston rod. The first position sensor is used for detecting the first sensing points, the second position sensor is used for detecting the second sensing points, and therefore discharge capacity and pumping directions of the hydraulic pump can be controlled according to detection of the first position sensor on the first sensing points or detection of the second position sensor on the second sensing points. Thus, the pumping mechanism can effectively reduce impact force generated by piston reversing, and can guarantee the maximum work stroke of a piston to improve pumping efficiency.

Description

technical field [0001] The invention relates to the technical field of material pumping, in particular to a pumping mechanism and a pump truck with the pumping mechanism. Background technique [0002] The pumping mechanism is driven by the piston rods of two series-connected oil cylinders to drive the two push heads to reciprocate in the two conveying cylinders, so that the two conveying cylinders alternately suck and push materials (such as concrete) and work. When the oil cylinder changes direction, it is required to achieve the following goals: (1) Small impact when changing direction; (2) Accurate lubrication position of the push head; (3) Maximize the utilization of the stroke of the main oil cylinder. [0003] The reversing control principle of the existing pumping mechanism is usually as follows: when the piston rod of an oil cylinder is retracted (that is, the compression stroke is performed), when one side edge of the induction sleeve enters the sensing range of the...

AI Technical Summary

Problems solved by technology

[0004] Therefore, in solving the reversing impact, the existing pumping mechanism often adopts to advance the buffer timing, reserve a larger buffer stroke, or simply reduce the displacement of the main oil pump when reversing in a certain proportion. These methods The effects are not the same, but the stability of the commutation is not high, and there are adverse effects such as reducing the suction efficiency

[0005] In addition, the existing pumping mechanism mostly adopts the method of judging and adjusting the hydraulic oil capacity in the connecting cavity of the two oil cylinders in order to solve the problem of fixed-point lubrication, so as to maintain the basic stability of the hydraulic oil capacity and make the lubrication point float within a certain range. It is necessary to add a pair of position sensors and hydraulic circuits, which increases the product cost. Drilling sensor installation holes on the oil cylinder will increase the oil leakage failure rate of the oil cylinder. The position adjustment accuracy of the lubrication point of this method is lower than the pumping speed. The lower is generally 40-50mm, and the error will increase when the pumping speed changes

[0006] The existing pumping mechanism has almost no control method in terms of cylinder stroke utilization. Whether it is hydraulic control reversing or electronic control reversing, the control point of the reversing command is determined based on the principle of not hitting the cylinder at the maximum pumping speed. , can not take care of the working strokes at various pumping speeds, so that when the pumping system is pumping at low and medium levels, the movement stroke of the piston rod is short, the suction efficiency of the delivery cylinder is low, and the pumping efficiency of the whole machine is low

Images