CN112729410B - Method for measuring displacement speed of piston of breaking hammer - Google Patents
Method for measuring displacement speed of piston of breaking hammer Download PDFInfo
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- CN112729410B CN112729410B CN202110021390.0A CN202110021390A CN112729410B CN 112729410 B CN112729410 B CN 112729410B CN 202110021390 A CN202110021390 A CN 202110021390A CN 112729410 B CN112729410 B CN 112729410B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D21/00—Measuring or testing not otherwise provided for
- G01D21/02—Measuring two or more variables by means not covered by a single other subclass
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D11/00—Component parts of measuring arrangements not specially adapted for a specific variable
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D11/00—Component parts of measuring arrangements not specially adapted for a specific variable
- G01D11/30—Supports specially adapted for an instrument; Supports specially adapted for a set of instruments
Abstract
The invention discloses a method for measuring the displacement speed of a piston of a breaking hammer, which comprises a gravel cage, an iron pier, a drill rod, a first bracket and a laser displacement sensor, wherein the gravel cage is arranged on the drill rod; the lower part of the gravel cage is sealed, the upper part of the gravel cage is provided with a hole, the interior of the gravel cage is of a cavity structure, the iron pier is arranged in the gravel cage, the iron pier is provided with a blind hole arranged in the vertical direction, a through hole arranged in the horizontal direction, and the blind hole is communicated with the through hole; the drill rod is provided with a through hole, and the lower end of the drill rod is connected with the upper end of the iron pier; the first support is a door-shaped support, a cross rod of the first support penetrates through the through hole, a laser displacement sensor is arranged on the cross rod, and a laser beam of the laser displacement sensor is upwards emitted from a blind hole of the iron pier through a through hole formed in the drill rod. The invention has the beneficial effects that: the method for observing the motion law of the piston through real-time measurement is firstly provided, and the displacement speed of the piston is accurately measured through the arrangement of the sensor, so that accurate data support is provided for product optimization.
Description
Technical Field
The invention belongs to the technical field of breaking hammers, and particularly relates to a device and a method for testing displacement and speed of a piston of a breaking hammer.
Background
The breaking hammer is widely applied to the fields of metallurgy, mines, railways, roads, buildings and the like due to the remarkable impact performance, high safety and reliability.
The breaking hammer has four working stages, namely piston return stroke, piston braking, piston stroke and drill rod striking. When the piston returns, the front cavity of the cylinder body is high-pressure oil, the rear cavity of the cylinder body is low-pressure oil, the piston moves upwards under the action of the hydraulic oil, when the piston moves to the top end, the piston brakes, the valve core of the reversing valve reverses, the front cavity and the rear cavity are both high-pressure oil, under the combined action of the nitrogen chamber and the pressure oil, the piston moves downwards in an accelerated manner, the drill rod is struck and then returns to brake, the valve core of the reversing valve reverses, a working cycle is completed, and the working process is continuously repeated under the action of the pressure oil.
How to ensure that the piston obtains the optimal impact force when striking the drill rod, namely ensuring that the piston just strikes the drill rod at the maximum speed as far as possible. The piston has a certain stroke from the top end to the striking rod, and the end of the stroke is the position where the piston strikes the rod, so the moment when the piston speed is maximum is the moment when the piston strikes the rod, and the moment when the speed is maximum is just the piston displacement to complete the stroke. The pressure and the flow of oil in an oil inlet pipeline and an oil return pipeline can be measured by adding a flowmeter on the oil inlet pipeline and the oil return pipeline, the pressure and the flow of each oil cavity in a rear cavity of the cylinder body and other hammer bodies are measured by externally connecting a sensor through a test hole, and then the change curves of the flow and the pressure value along with time can be obtained. Monitoring of the velocity and displacement of the piston is much more difficult. At present, the speed and displacement monitoring of the piston can only be predicted in a software simulation mode. And adjusting the hydraulic oil circuit according to the simulation result to seek the optimal output mode. Because the numerical error of simulation is larger, the striking process time is short, the speed is large, and a slight error can cause dislocation. It is difficult to determine whether the piston is the drill rod that strikes at the moment of maximum speed. For example, the piston has not yet accelerated to the maximum speed when striking the drill rod, which may cause a problem of insufficient striking force; alternatively, the speed may reach a maximum already before the piston strikes the drill rod, which may result in energy waste and/or insufficient striking force. That is, the matching degree of the piston displacement and the speed is not accurate, which causes the problem that the piston cannot be guaranteed to hit the drill rod at the moment of the maximum speed.
Disclosure of Invention
The device and the method for testing the piston displacement speed of the breaking hammer are provided, and the device and the method for testing the piston displacement speed of the breaking hammer are used for solving the problems that in the prior art, simulation results of piston displacement and speed are inaccurate, and the matching degree is unstable, so that the piston cannot be guaranteed to just hit a drill rod at the moment of maximum speed, and therefore the optimal impact force cannot be obtained.
A device for testing displacement speed of a piston of a breaking hammer comprises a foam buffer wall, a stone breaking cage, an iron pier, a drill rod, a first support, a second support, a white light speed sensor and a laser displacement sensor; the foam buffer wall is vertically embedded in the foundation and is connected end to end, so that the foundation is divided into an inner part and an outer part; the lower part of the gravel cage is sealed, the upper part of the gravel cage is provided with a hole, the interior of the gravel cage is of a cavity structure, and the gravel cage is vertically embedded in a foundation surrounded by a foam buffer wall; the iron piers are arranged in the gravel cage, and are provided with blind holes arranged in the vertical direction and through holes arranged in the horizontal direction, and the blind holes are communicated with the through holes; the drill rod is provided with an inner hole which is communicated up and down, and the lower end of the drill rod is connected with the upper end of the iron pier; the first support is a door-shaped support, bases on two sides of the first support are arranged on the foam buffer wall, a cross rod of the first support penetrates through the through hole, a laser displacement sensor is arranged on the cross rod, and a laser beam of the laser displacement sensor is upwards emitted from a blind hole of the iron pier through an inner hole formed in the drill rod; the second support is a door-shaped support, bases on two sides of the second support are arranged on the foam buffer wall, a cross rod of the second support is arranged on one side of the drill rod, and a white light speed sensor is arranged on the cross rod; the side surface of the front shell of the breaking hammer is provided with an elongated slot, the front shell is sleeved at the upper end of a drill rod, and the drill rod can slide up and down in the front shell; the white light speed sensor is aligned with the position of the long groove.
Preferably, the device for testing the displacement speed of the piston of the breaking hammer is characterized in that the lower part of the gravel cage is a cylindrical cavity, and the upper part of the gravel cage is a rectangular cavity.
Preferably, the hammer piston displacement speed testing device, the iron pier has the cylinder with the cylindrical cavity looks adaptation of lower part, the cuboid with the rectangle cavity looks adaptation of upper portion.
Preferably, the device for testing the displacement speed of the piston of the breaking hammer is characterized in that an observation hole is formed in the side wall of the iron pier and is communicated with the through hole.
Preferably, the lower end of the drill rod is fixedly connected with the upper end of the iron pier through interference fit.
A measuring method of displacement speed of a piston of a breaking hammer is characterized in that a test board is built by adopting the measuring device, a foam buffer wall is embedded in a foundation, the foam buffer wall is vertically embedded and connected end to end, the foundation is divided into an inner part and an outer part, bases on two sides of a first support are arranged on the foam buffer wall, and bases on two sides of a second support are arranged on the foam buffer wall; vertically embedding a gravel cage in the middle of a foundation surrounded by a foam buffer wall, installing a breaking hammer at the upper end of a drill rod, exposing the side wall of a piston of the breaking hammer by arranging an elongated slot at the side position of the breaking hammer, and measuring the speed of the piston in real time by arranging a speed sensor in alignment with the elongated slot; and acquiring detection data of the speed sensor and the laser displacement sensor by the data acquisition instrument.
The invention has the beneficial effects that:
1. firstly, a method for observing the motion rule of the piston through real-time measurement is provided, and the displacement speed of the piston is accurately measured through the arrangement of a sensor, so that accurate data support is provided for product optimization;
2. the measurement can be carried out on the main machines with different specifications of the medium-sized and large-sized breaking hammer, and the application range is wide.
Drawings
FIG. 1 is a perspective view of one embodiment of the present invention;
FIG. 2 is a cross-sectional view of one embodiment of the present invention;
FIG. 3 is a diagram illustrating a test state according to an embodiment of the present invention;
FIG. 4 is a schematic view of a drill rod according to an embodiment of the present invention;
FIG. 5 is a schematic view of a hot metal pier according to an embodiment of the invention;
FIG. 6 is a schematic view of a gabion according to an embodiment of the invention;
fig. 7 is a schematic view of the slotting of the front shell of the breaking hammer according to one embodiment of the invention.
Detailed Description
The technical scheme of the invention is further explained by combining the attached drawings in the embodiment of the invention.
As shown in fig. 1, 2 and 3, the device for testing the displacement speed of the piston of the breaking hammer comprises a foam buffer wall 2, a stone breaking cage 3, an iron pier 4, a drill rod 5, a first bracket 6, a second bracket 7, a white light speed sensor 71 and a laser displacement sensor 61. The foam buffer wall 2 is vertically buried in the foundation 1 and connected end to divide the foundation 1 into an inner part and an outer part.
As shown in fig. 6, the gravel cage 3 is closed at the lower part and opened at the upper part, the interior of the gravel cage is a cavity structure, the lower part 31 of the gravel cage is a cylindrical cavity, the upper part 32 of the gravel cage is a rectangular cavity, the cylindrical cavity and the rectangular cavity are communicated with each other, and the gravel cage 3 is vertically embedded in the foundation 1 surrounded by the foam cushioning wall 2.
As shown in fig. 5, the metal pier 4 has a cylinder 42 adapted to the cylindrical cavity of the lower portion 31 and a rectangular parallelepiped 44 adapted to the rectangular cavity of the upper portion 32, the metal pier 4 has a through hole penetrating vertically, the rectangular parallelepiped 44 has a through hole 41, the side wall has an observation hole 43, the observation hole 43 communicates with the through hole 41, and the metal pier 4 is disposed in the gabion 3.
As shown in fig. 4, the drill rod 5 is provided with an inner hole 51 which is through up and down, and the lower end of the drill rod 5 is connected with the upper end of the iron pier 4;
the first support 6 is a door-shaped support, bases on two sides are arranged on the foam buffer wall 2, a cross rod of the first support passes through the through hole 41, a laser displacement sensor 61 is arranged on the cross rod, and a laser beam of the laser displacement sensor 61 is upwards ejected from inner holes formed in the iron pier 4 and the drill rod 5 and is ejected onto the end face of the piston. The laser displacement sensor and the cross rod are arranged in a suspended mode and are not in contact with the iron pier. In the process of the broken stone hit by the iron pier, the laser displacement sensor is fixed, and the displacement of the piston is stably measured.
The second support 7 is a door-shaped support, bases on two sides of the second support are arranged on the foam buffer wall 2, a cross rod of the second support is arranged on one side of the drill rod 5, and a white light speed sensor 71 is arranged on the cross rod.
When the displacement and the speed of the piston are measured, a square pit with a certain size is formed in the flat ground, and a foam buffer zone is laid around the pit to reduce the test error caused by the vibration of heavy machinery. Completely attaching the broken stone cage to the pit, adding large broken stones into the broken stone cage so as to receive impact energy when being struck by a breaking hammer, and replacing the broken stones in the broken stone cage after being broken; the upper end of garrulous gabion is put into to the test iron heading, and the cylinder of iron heading lower extreme is the guide effect, makes the iron heading can not slope from top to bottom perpendicularly, and the both ends of iron heading are the fluting respectively, and the channel-section steel is put into in the groove of full-open and is used for holding laser displacement sensor, and whether half-open groove is used for observing the mounted position of sensor reasonable. The laser of the laser displacement sensor is shot from the middle part of the drill rod to the bottom surface of the piston, and then the laser signal reflected from the bottom surface of the piston is received, so that the displacement of the piston is measured in real time. The drill rod is connected with the iron upset in an interference fit mode, and the drill rod is prevented from falling off.
As shown in fig. 7, when the construction machine is used, the construction machine is opened to a position near the foundation, the breaking hammer 8 is installed, the upper end of the drill rod 5 extends into the shell of the breaking hammer 8, the side surface of the front shell 10 is provided with a long groove 101, the piston moves up and down in the front shell 10, the upper end of the drill rod 5 is repeatedly hammered, the white light speed sensor 71 is aligned with the position of the long groove 101, and the real-time speed of the piston 9 is measured. Different test drill rods can be replaced according to different types of breaking hammers, so that the data of the operation of the breaking hammers can be accurately measured, and data support is provided for product optimization and new product research and development.
The speed and the displacement of the piston can be measured simultaneously, and mutual verification can be carried out. The piston is of a stroke, and when the speed reaches the maximum value, the displacement should be at the end of the stroke, i.e. the moment of striking the drill rod, and the accuracy of the speed is verified by the displacement.
The displacement of the piston of the breaking hammer is very small, the time is very short, and in order to ensure the accuracy of the displacement measured instantly, a foam buffer strip is firstly paved beside a test area, so that the error caused by mechanical vibration is reduced. The installation of garrulous gabion and ground, the installation between the part need be controlled the clearance, avoids rocking, the error that the slope scheduling problem brought. The door type support needs to be installed in the foam buffering area, reduces the vibration error of sensor, guarantees that laser can vertically hit the piston bottom surface, and the guide effect of iron heading can make the operation equipment vertical from top to bottom, is parallel with the laser direction. The top of the drill rod has the same appearance as an actual drill rod, so that the drill rod can be installed more practically and accords with daily operation.
The ultimate goal is to achieve the optimum impact force, i.e., the maximum striking force when the piston strikes the drill rod, because products sometimes suffer from insufficient striking force. However, it is difficult to determine whether the piston is a drill rod that is hit at the time of the maximum speed only by the data curve of the pressure of each oil chamber, and the hitting force may be insufficient before or after the peak of the speed, which may cause energy waste and reduce the energy utilization rate. We want the piston to hit the drill rod at the time of maximum speed, i.e. at the time of maximum impact force. A curve of velocity versus a curve of pressure is required.
The measurement of the displacement can achieve the effect of comparing and verifying the accuracy of the speed, and meanwhile, the displacement can be compared and analyzed with the measured pressure of the oil cavity on a curve chart. The speed and displacement data curve of the piston is obtained through an experimental platform. And the pressure and flow measurement data in the hydraulic cavity are combined and put into the same curve chart through a data acquisition instrument, so that the pressure, the speed, the displacement and the flow at the moment can be simultaneously seen at each time node, and the matching problem of the state node is analyzed, namely whether the drill rod is just hit at the moment with the maximum speed or not is solved, namely the displacement completes the whole stroke. Is apparent from a data map. If the matching problem difference is large, the state of the point of the state node can be analyzed according to the reasons generated by the curve chart, for example, whether the piston reaches the tail end or not and whether the reversing valve has reversed or not, and only if each state node is analyzed, the structure of the existing product can be improved in a targeted manner, so that the product can be optimized. The final purpose is to obtain a comprehensive curve with pressure, flow, speed and displacement, and each parameter can be analyzed on the same time node.
A measuring method of displacement speed of a piston of a breaking hammer is characterized in that a test board is built by adopting the measuring device, a foam buffer wall 2 is embedded in a foundation 1, the foam buffer wall 2 is vertically embedded and connected end to end, the foundation 1 is divided into an inner part and an outer part, bases on two sides of a first support 6 are arranged on the foam buffer wall 2, and bases on two sides of a second support 7 are arranged on the foam buffer wall 2; vertically embedding a gravel cage 3 in the middle of a foundation 1 surrounded by a foam buffer wall 2, installing a breaking hammer at the upper end of a drill rod 5, exposing the side wall of a piston 9 of the breaking hammer by arranging a long groove 101 at the side position of the breaking hammer, arranging a speed sensor 71 in alignment with the long groove 101, and measuring the speed of the piston 9 in real time; the detection data of the speed sensor 71 and the laser displacement sensor 61 are collected by a data collector.
A hydraulic circuit calibration method for a breaking hammer is characterized in that the displacement and the speed of a piston of the breaking hammer are measured in real time through a breaking hammer piston displacement speed testing device; the pressure and the flow of oil in an oil inlet pipeline and an oil return pipeline of the breaking hammer can be measured by adding a flowmeter on the oil inlet oil return pipeline, and the pressure and the flow of an oil cavity in a cylinder body of the breaking hammer are measured in real time by externally connecting a sensor on an opening of a hammer body; collecting the flow pressure sensor, the displacement sensor and the speed sensor through a data acquisition instrument to obtain a comprehensive curve with pressure, flow, speed and displacement; analyzing the maximum speed which can be reached by the piston in the acceleration process according to the comprehensive curve; and adjusting a buffer of the oil inlet pipeline or a buffer of the oil return pipeline to delay or advance the time point when the piston reaches the maximum speed, so that the piston displacement at the time point just reaches the rod end of the drill rod to strike and output the drill rod.
It will be appreciated that although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (1)
1. A measuring method for displacement speed of a piston of a breaking hammer is characterized in that a test bench is built by adopting a measuring device, wherein the measuring device comprises a gravel cage (3), an iron pier (4), a drill rod (5), a first support (6) and a laser displacement sensor (61); the upper part of the gravel cage (3) is provided with a hole, and the inner part of the gravel cage is of a cavity structure; the iron pier (4) is arranged in the gravel cage (3), the iron pier (4) is provided with a blind hole arranged in the vertical direction and a through hole (41) arranged in the horizontal direction, and the blind hole is communicated with the through hole (41); the drill rod (5) is provided with an inner hole (51) which is communicated up and down, and the lower end of the drill rod (5) is connected with the upper end of the iron pier (4); the first support (6) is a door-shaped support, a cross rod of the first support penetrates through the through hole (41), a laser displacement sensor (61) is arranged on the cross rod, and a laser beam of the laser displacement sensor (61) is upwards emitted from a blind hole of the iron pier (4) through an inner hole formed in the drill rod (5);
the measuring device further comprises a second support (7) and a speed sensor (71), the second support (7) is a door-shaped support, a cross rod of the second support is arranged on one side of the drill rod (5), and the speed sensor (71) is arranged on the cross rod;
embedding a foam buffer wall (2) in a foundation (1), vertically embedding the foam buffer wall (2) and connecting the foam buffer wall end to end, dividing the foundation (1) into an inner part and an outer part, arranging bases on two sides of a first support (6) on the foam buffer wall (2), and arranging bases on two sides of a second support (7) on the foam buffer wall (2); vertically embedding a gravel cage (3) in the middle of a foundation (1) surrounded by a foam buffer wall (2), installing a breaking hammer at the upper end of a drill rod (5), exposing the side wall of a piston (9) of the breaking hammer by arranging a long groove (101) at the side position of the breaking hammer, arranging a speed sensor (71) aiming at the long groove (101), and measuring the speed of the piston (9) in real time; the data acquisition instrument acquires detection data of the speed sensor (71) and the laser displacement sensor (61).
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| Application Number | Priority Date | Filing Date | Title |
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| CN202110021390.0A CN112729410B (en) | 2021-01-08 | 2021-01-08 | Method for measuring displacement speed of piston of breaking hammer |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202110021390.0A CN112729410B (en) | 2021-01-08 | 2021-01-08 | Method for measuring displacement speed of piston of breaking hammer |
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| CN112729410A CN112729410A (en) | 2021-04-30 |
| CN112729410B true CN112729410B (en) | 2021-09-03 |
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Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4167912B2 (en) * | 2003-02-21 | 2008-10-22 | 独立行政法人産業技術総合研究所 | Rock stress measuring device |
| CN202229870U (en) * | 2011-10-11 | 2012-05-23 | 中国石油化工股份有限公司 | Petroleum drilling well impacter performance test device |
| CN202362104U (en) * | 2011-11-01 | 2012-08-01 | 上海工程技术大学 | Impact energy detection device for hydraulic breaking hammer |
| CN103485383A (en) * | 2013-09-30 | 2014-01-01 | 江苏柳工机械有限公司 | Quartering hammer system and control method thereof |
| CN103675319B (en) * | 2013-11-28 | 2015-12-30 | 三一重机有限公司 | Quartering hammer impact velocity proving installation and method |
| CN106908226B (en) * | 2015-12-22 | 2020-09-04 | 中国石油天然气集团公司 | Performance testing device and method for horizontal directional drilling crossing percussion drill |
| CN108561071A (en) * | 2018-06-21 | 2018-09-21 | 姚小林 | Electric-controlled hydraulic quartering hammer |
| CN109406306A (en) * | 2018-10-24 | 2019-03-01 | 北京延锋北汽汽车内饰件有限公司 | A kind of drop hammer impact testing machine |
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