CN103604716B - Screw rod spiral groove accelerated wear test machine and test method thereof - Google Patents

Screw rod spiral groove accelerated wear test machine and test method thereof Download PDF

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Publication number
CN103604716B
CN103604716B CN201310618319.6A CN201310618319A CN103604716B CN 103604716 B CN103604716 B CN 103604716B CN 201310618319 A CN201310618319 A CN 201310618319A CN 103604716 B CN103604716 B CN 103604716B
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China
Prior art keywords
screw mandrel
axis
guide
spiral groove
base
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Expired - Fee Related
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CN201310618319.6A
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CN103604716A (en
Inventor
李助军
陆蕊
蒋新革
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Guangzhou Railway Polytechnic
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Guangzhou Railway Polytechnic
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Abstract

The invention discloses a kind of screw rod spiral groove accelerated wear test machine, including base, the screw mandrel bottom plate that is installed on base and screw mandrel upper mounted plate, for driving the driving means of screw mandrel to be measured, also including balancing weight guide rod, the axis of guide base being movably connected on described balancing weight guide rod, described axis of guide base has for the axis of guide with the helicla flute matched in clearance of screw mandrel to be measured.Described driving means drives the rotating that screw mandrel to be measured rotates, the axis of guide coordinated by helicla flute therewith, rotary motion is changed into the linear motion repeatedly of setting base for counter weight and the axis of guide.According to wear modelBy increasing the axis of guide surface pressing p to screw mandrel to be measured, can realize shortening test period.The present invention also provides for a kind of test method utilizing above-mentioned screw rod spiral groove accelerated wear test machine.

Description

Screw rod spiral groove accelerated wear test machine and test method thereof
Technical field
The accelerated wear test machine of a kind of screw mandrel wearability and test method thereof, specifically refer to a kind of screw rod spiral groove side The accelerated wear test machine of wearability and test method thereof.
Background technology
Impact printer, the screw rod transmission pair on the most miniature impact printer is the key mechanism of printer.Along with The growth in printer miscellaneous part life-span, people are more and more higher to the requirement in printer life-span and print quality.The most the father-in-law The mini-printer of department claims that machine life is 12,000,000 row, and this just requires screw mandrel and the axis of guide, and friction pair is printed guaranteeing by this The life-span that machine occurs without that word mechanism of car is stuck, print the faults such as step-out is 1.2 × 107 row, and the requirement of such high life result in The wearability of screw rod transmission pair is far from meeting requirement.In order to develop the reasonable screw mandrel of wearability, research worker has been done greatly Quantifier elimination works, but is finally required for doing screw mandrel abrasion test, and current impact printer manufacturer generally takes reality Border makes experimentally to carry out the evaluation of screw rod transmission pair wearability.If print 30,000 row calculating continuously (every day beats by every day Print 8 hours), printing 12,000,000 row needs 400 days.Can take to arrange round the clock that personnel are on duty continuous beats to shorten test period The method of print, but the test period also tend to need 3-4 month, do not meet the timeliness demand of reality.
Summary of the invention
In order to shorten the abrasion test time, the invention reside in the defect overcoming prior art, it is provided that a kind of screw mandrel spiral Groove accelerated wear test machine and test method thereof.
Its technical scheme is as follows:
A kind of screw rod spiral groove accelerated wear test machine, the screw mandrel bottom plate including base, being installed on base and silk Bar upper mounted plate, for driving the driving means of screw mandrel to be measured, also include balancing weight guide rod, be movably connected on described balancing weight and lead Axis of guide base on bar, described axis of guide base has for the axis of guide with the helicla flute matched in clearance of screw mandrel to be measured.
Described driving means drives the rotating that screw mandrel to be measured rotates, by the axis of guide of helicla flute matched in clearance therewith, Rotary motion is changed into the linear motion repeatedly of setting base for counter weight and the axis of guide.According to wear modelBy increasing The big axis of guide surface pressing p to screw mandrel to be measured, can realize shortening test period.
Further, described axis of guide base is provided with the balancing weight that can change.Realized quickly by replacing balancing weight, Change the axis of guide simply and treat the surface pressing p of lateral filament bar, thus obtain organizing test data more.
Further, the cross section of described axis of guide base is U shape, and it includes the recess and two of medial recess Two protuberances that side is protruded, the described axis of guide protrudes from described recess, has installing hole above described protuberance, and described balancing weight leads to Cross installing hole to be arranged on described axis of guide base.
Further, two protuberances of axis of guide base being respectively provided with through hole, described axis of guide base is by above-mentioned counterweight Block guide rod coordinates through its through hole with balancing weight guide rod, so that axis of guide base is the most limited, the most limited Between screw mandrel bottom plate and screw mandrel upper mounted plate, preferably limit the fortune of straight line repeatedly of axis of guide base and balancing weight guide rod Dynamic direction.
Further, malthoid is installed in through hole, is connected with above-mentioned balancing weight guide rod by malthoid, thus alleviates the most anti- The abrasion only caused due to the relative displacement between axis of guide base and balancing weight guide rod, and then extend screw rod spiral groove acceleration The service life of abrasion tester.
Further, described base includes vertical component effect and horizontal part, and vertical component effect offers vertical channel, described lower screw mandrel Fixed plate is arranged on vertical component effect with coordinating of vertical channel by fixed component.
Further, the vertical component effect of described base offers two vertical channel, and said two vertical channel is parallel to each other, and makes Obtain screw mandrel bottom plate and can be selectively installed at the various location of described vertical channel so that screw rod spiral groove accelerated wear test Testing machine can realize the wearability test of different length screw mandrel.
Further, described driving means includes the canine tooth that on the main shaft of stepper and stepper, logical interference fit is installed Wheel and the little gear engaged with described gear wheel, coordinate face to be connected handle by little gear with the different in nature convex-concave profile of tooth of screw mandrel to be measured Rotary motion passes to screw mandrel.
A kind of test method utilizing above-mentioned screw rod spiral groove accelerated wear test machine, comprises the following steps:
The measurement initiating terminal of S1: labelling screw mandrel;
S2: the central axis along screw mandrel is rule;
S3: measure initiating terminal from screw mandrel and measure screw rod spiral groove original width A1, A2, A3 successively along line vestige ... An;
S4: install screw mandrel in the screw rod spiral groove accelerated wear test machine described in the claims 1-8 any one, Carry out screw mandrel wear testing recording test time;
S5: measure initiating terminal from screw mandrel and measure width B1, the B2 of screw mandrel abrasion rear screw groove along line vestige successively, B3 ... Bn;
S6: utilizeScrew mandrel wear extent w being calculated in the testing time.
According to wear model(w is the wear extent of screw rod spiral groove to be measured, and k is between helicla flute and the axis of guide Coefficient of friction, x is the relative shift between helicla flute and the axis of guide, and p is spiral fluted surface pressing, and H is the hard of screw mandrel Degree), the p value drawn by the weight of axis of guide base calculates the wear extent of screw rod spiral groove to be measured, thus realizes screw mandrel spiral shell The accelerated wear test of spin slot.
Further, between step S4 and S5, also include the step utilizing ultrasonic waves for cleaning screw mandrel.
Accompanying drawing explanation
Fig. 1 is the signal of the accelerated wear test machine of impact printer screw rod spiral groove wearability described in the embodiment of the present invention Figure.
Fig. 2 is the guiding of the accelerated wear test machine of impact printer screw rod spiral groove wearability described in the embodiment of the present invention The enlarged drawing at another visual angle of axle base.
Fig. 3 is the screw mandrel signal of the test method of the screw rod spiral groove accelerated wear test machine described in the embodiment of the present invention Figure.
Description of reference numerals:
1. balancing weight guide rod 2. screw mandrel bottom plate 3. axis of guide base 4. screw mandrel upper mounted plate 5. gear wheel 6. motor fixing plate 7. motor 8. little gear 9. screw mandrel 10. balancing weight 11. base 12. axis of guide 30. recess 31. protuberance 32. installing hole 33. through hole 90. helicla flute 100. screw rod spiral groove accelerated wear test machines 110. vertical channel 111. vertical component effect 112. horizontal part 113. bolts
Detailed description of the invention
Below embodiments of the invention are described in detail:
As it is shown in figure 1, the screw rod spiral groove accelerated wear test machine 100 of the present invention includes under balancing weight guide rod 1, screw mandrel solid Determine plate 2, axis of guide base 3, screw mandrel upper mounted plate 4, gear wheel 5, motor fixing plate 6, motor 7, little gear 8, balancing weight 10, base 11.Base 11 be shape of cross section be the sheet metal component of inverted " t " font, it includes vertical component effect 111 and horizontal part 112. Vertical channel 110 is offered on the vertical component effect 111 of base plate 11.In the present embodiment, the quantity of described vertical channel 110 is two, and Described two vertical channel 110 are parallel to each other.Described screw mandrel bottom plate 2, screw mandrel upper mounted plate 4 and motor fixing plate 6 are transversal The sheet metal component that face shape is L-shaped, and be installed on the vertical component effect 111 of described base plate 11 by bolt 113.Wherein, screw mandrel Bottom plate 2 is coordinated with described two vertical channel 110 by bolt 113 and is installed on described vertical component effect 111.In another embodiment In, the shape of cross section of described screw mandrel bottom plate 2, screw mandrel upper mounted plate 4 and motor fixing plate 6 can also in T-shape or Other shapes of person.Described motor 7 is arranged on motor fixing plate 6.On the main shaft of motor 7, logical interference fit installs institute State gear wheel 5.One end of described balancing weight guide rod 1 is arranged on screw mandrel upper mounted plate 4, and the other end of balancing weight guide rod 1 passes through Screw mandrel bottom plate 2 is installed on the pedestal 11.
As in figure 2 it is shown, the cross section of described axis of guide base 3 is U shape, it include the recess 30 of medial recess with And two protuberances 31 that both sides are protruded.An axis of guide 12 is protruded out on described recess 30.Above described protuberance 31, there is installing hole 32. In the present embodiment, each protuberance 31 has two installing holes 32, then by two installing holes 32 and above-mentioned balancing weight 10 Connect.Balancing weight 10 has the installation tenon (not shown) corresponding with described installing hole 32.Divide on two protuberances 31 of axis of guide base 3 Not having through hole 33, each through hole 33 medial surface is separately installed with malthoid (not shown).Described axis of guide base 3 is joined by above-mentioned Pouring weight guide rod 1 coordinates through its through hole 33 with balancing weight guide rod 1 so that axis of guide base 3, the most limited, is longitudinally being limited Between screw mandrel bottom plate 2 and screw mandrel upper mounted plate 4.Owing to having malthoid in through hole 33, malthoid can alleviate the most anti- Stop the abrasion caused due to the relative displacement between axis of guide base 3 and balancing weight guide rod 1, and then prolongation screw rod spiral groove adds The service life of speed abrasion tester 100.
Screw mandrel 9 to be tested is one for the screw mandrel 9 of impact printer, and its surface has some helicla flutes 90.Especially, Described screw mandrel 9 to be tested is for miniature impact printer.Described screw mandrel 9 to be tested is from the recess of above-mentioned axis of guide base 3 30 pass, and its one end is arranged on screw mandrel bottom plate 2, and other end is arranged on screw mandrel upper mounted plate 4, and through described silk Bar upper mounted plate 4 is connected with described little gear 8.Preferably, described screw mandrel 9 fits through profile of tooth with little gear 8 and is connected.Institute State gear wheel 5, with described little gear 8, gear motion occurs.The above-mentioned axis of guide 12 forms matched in clearance with the helicla flute 90 of screw mandrel 9, And in helicla flute 90 slide inside friction.Screw mandrel 9 drives balancing weight 10, axis of guide base 3 to do upper and lower straight line by the axis of guide 12 Motion.It is installed on described vertical component effect 111 owing to screw mandrel bottom plate 2 is coordinated with described two vertical channel 110 by bolt 113, Therefore screw mandrel bottom plate 2 can be selectively installed at the various location of described vertical channel 110 so that screw rod spiral groove adds Speed abrasion tester 100 can realize the wearability test of different length screw mandrel 9.
When the screw rod spiral groove accelerated wear test machine 100 of the embodiment of the present invention works, motor 7 rotates, by greatly Gear 5 and the gear motion of little gear 8, pass to little gear 8 rotary motion, and little gear 8 and screw mandrel 9 are by opposite sex convex and concave teeth Shape coordinates face connection that rotary motion is passed to screw mandrel 9 thus drives screw mandrel 9 to rotate;Screw mandrel 9 is rotated through helicla flute 90 therewith The axis of guide 12 coordinated, is changed into setting base for counter weight 3, balancing weight 10 and the linear motion of the axis of guide 12 rotary motion.Stepping Motor 7 can realize accelerating rotation, positive and negative rotation by the control of panel or Artificial Control, thus realizes setting base for counter weight 3, balancing weight 10 and the acceleration of the axis of guide 12, repeatedly move along a straight line.Screw mandrel 9 drives the axis of guide 12 to drive setting base for counter weight 3, counterweight Block 10 and the axis of guide 12 do and move along a straight line up and down, it is achieved wear test.
As it is shown on figure 3, the test utilizing above-mentioned screw rod spiral groove accelerated wear test machine 100 described in the embodiment of the present invention Method comprises the following steps:
The measurement initiating terminal of S1: labelling screw mandrel 9.
Specifically, marking at screw mandrel 9 end face to be measured with scriber, screw mandrel 9 one end indicates mark, and then to become measurement initial End.
S2: the central axis along screw mandrel 9 is rule.
Specifically, utilize vernier height gauge or the diameter of miking screw mandrel to be measured 9, measure many at diverse location Secondary, it is preferable that pendulous frequency is three times, average and obtain the diameter of screw mandrel 9, then vernier height gauge is adjusted to half high Degree is also rule along screw mandrel 9 axle.
S3: measure the original width A of the helicla flute 90 of screw mandrel 9.
Specifically, ruling, screw mandrel 9 is put under optical profilometer, depends on along line vestige from the measurement initiating terminal of screw mandrel 9 Original width A1, A2, the A3 of secondary measurement screw mandrel 9 helicla flute 90 ... An.
S4: install screw mandrel in above-mentioned screw rod spiral groove accelerated wear test machine 100, carry out the wear testing of screw mandrel 9 also Recording test time.
Specifically, screw mandrel 9 one end to be measured is arranged on screw mandrel bottom plate 2, and card upper shed back-up ring;Other end is worn After crossing screw mandrel upper mounted plate 4 and being connected with described little gear 8 and card upper shed back-up ring, prevent screw mandrel from coming off in an experiment. Drive described screw mandrel to be measured 9 to rotate and drive described guiding by the axis of guide with helicla flute 90 matched in clearance of screw mandrel 9 to be measured Axle base 11 is for linear motion, and records test time started t1 and test end time t2, and (t2-t1) is the testing time.
S5: measure width B after helicla flute 90 abrasion of silk 9.
Specifically, abrasion filament bar 9 is put under optical profilometer, measures initiating terminal along line vestige successively from screw mandrel 9 Measure screw mandrel 9 to wear and tear width B1, B2, the B3 of rear screw groove 90 ... Bn.
S6: seek screw mandrel wear extent w.WithIt is calculated the testing time for screw mandrel mill time (t2-t1) Damage amount w.
It is to be appreciated that also include the step utilizing ultrasonic waves for cleaning screw mandrel between step S4 and S5.
According to Archard wear model(w is the wear extent of sample, and k is coefficient of friction, and x is between friction pair Relative shift, p is the surface pressing of sample, and H is the hardness of sample), it is known that wear extent W and coefficient of friction, surface pressing With the relative shift between friction pair is directly proportional, it is inversely proportional to the hardness of sample.If therefore the suitable balancing weight 10 that increases Weight just can increase the surface pressing p of sample, can realize shortening test period.
It is to be appreciated that the screw rod spiral groove accelerated wear test machine 100 of the present invention is not limited to utilize between gear Gear motion passes to screw mandrel 9 rotary motion, as long as the driving means that screw mandrel 9 rotates can be driven.The silk of the present invention It is to utilize bolt 113 to fix on described screw mandrel bottom plate 2, screw mandrel that bar spiral groove accelerated wear tester 100 does not the most limit Fixed plate 4 and motor fixing plate 6, as long as the fixed component of above-mentioned plate can be installed.
The screw rod spiral groove accelerated wear test machine 100 of the present invention is that a kind of simulation actually used situation of screw mandrel 9 accelerates mill On the one hand damaging testing machine, relatively actual service test method significantly shortens the abrasion test time, still further aspect due to Simple to operate, can be drawn by change experiment condition and organize experimental data more so that experimental result relatively laboratory test specimen experimental technique Have more practical value.Further, the simple in construction of the screw rod spiral groove accelerated wear test machine 100 due to the present invention, cost Low, it is adaptable to industry is promoted the use of.
Embodiment described above only have expressed the detailed description of the invention of the present invention, and it describes more concrete and detailed, but also Therefore the restriction to the scope of the claims of the present invention can not be interpreted as.It should be pointed out that, for those of ordinary skill in the art For, without departing from the inventive concept of the premise, it is also possible to make some deformation and improvement, these broadly fall into the guarantor of the present invention Protect scope.

Claims (8)

1. a screw rod spiral groove accelerated wear test machine, the screw mandrel bottom plate including base, being installed on base and screw mandrel Upper mounted plate, for driving the driving means of screw mandrel to be measured, it is characterised in that: also include balancing weight guide rod, be movably connected on institute State the axis of guide base on balancing weight guide rod, described axis of guide base have for the helicla flute matched in clearance of screw mandrel to be measured The axis of guide, described axis of guide base is provided with the balancing weight that can change, and described base includes vertical component effect and horizontal part, vertically Offering vertical channel in portion, described screw mandrel bottom plate is arranged on vertical component effect with coordinating of vertical channel by fixed component.
2. screw rod spiral groove accelerated wear test machine as claimed in claim 1, it is characterised in that: the horizontal stroke of described axis of guide base Cross section is U shape, and two protuberances that it recess including medial recess and both sides are protruded, the described axis of guide is from described recessed Portion protrudes, and has installing hole above described protuberance, and described balancing weight is arranged on described axis of guide base by installing hole.
3. screw rod spiral groove accelerated wear test machine as claimed in claim 2, it is characterised in that: two protuberances of axis of guide base On be respectively provided with through hole, described axis of guide base is coordinated with balancing weight guide rod through its through hole by above-mentioned balancing weight guide rod.
4. screw rod spiral groove accelerated wear test machine as claimed in claim 3, it is characterised in that: malthoid is installed in through hole, It is connected with above-mentioned balancing weight guide rod by malthoid.
5. screw mandrel bottom plate screw rod spiral groove as claimed in claim 1 accelerated wear test machine, it is characterised in that: the described end The vertical component effect of seat offers two vertical channel, and said two vertical channel is parallel to each other.
6. screw rod spiral groove accelerated wear test machine as claimed in claim 1, it is characterised in that: described driving means includes step Enter motor and the gear wheel installed on the main shaft of motor and the little tooth engaged with described gear wheel by interference fit Wheel.
7. the test side of the screw rod spiral groove accelerated wear test machine that a kind utilizes described in the claims 1-6 any one Method, comprises the following steps:
The measurement initiating terminal of S1: labelling screw mandrel;
S2: the central axis along screw mandrel is rule;
S3: measure initiating terminal from screw mandrel and measure screw rod spiral groove original width A1, A2 successively along line vestige, A3, An;
S4: install screw mandrel in the screw rod spiral groove accelerated wear test machine described in the claims 1-6 any one, carry out Screw mandrel wear testing recording test time;
S5: measure initiating terminal from screw mandrel and measure width B1, the B2 of screw mandrel abrasion rear screw groove along line vestige successively, B3, Bn;
S6: utilizeScrew mandrel wear extent w being calculated in the testing time.
8. test method as claimed in claim 7, it is characterised in that: also include utilizing ultrasound wave clear between step S4 and S5 Wash the step of screw mandrel.
CN201310618319.6A 2013-11-27 2013-11-27 Screw rod spiral groove accelerated wear test machine and test method thereof Expired - Fee Related CN103604716B (en)

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CN103604716B true CN103604716B (en) 2016-10-05

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Publication number Priority date Publication date Assignee Title
CN104792640B (en) * 2015-04-08 2018-02-23 东南大学 A kind of ball screw assembly, wear measurement testing stand
CN108195700B (en) * 2017-12-26 2020-04-24 重庆程顺汽车配件制造有限公司 Tire wear test structure and manufacturing method thereof

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2273015Y (en) * 1996-10-09 1998-01-21 大连海事大学 Reciprocating flat surface wear test machine
CN2686752Y (en) * 2004-03-15 2005-03-23 中国第二十冶金建设公司检修协力分公司 Blooming mill screwdown screw wear measuring device
CN101701890A (en) * 2009-10-27 2010-05-05 华南理工大学 Abrasion test method for determining rational hardness pairing of friction pair
CN101994803A (en) * 2010-11-19 2011-03-30 成都焊研威达科技股份有限公司 Lifting nut pair with wear detector
CN102445340B (en) * 2011-09-30 2013-08-07 优励聂夫(南京)科技有限公司 Running-in testing method of loading running-in device for ball screw pair
CN203772665U (en) * 2013-11-27 2014-08-13 广州铁路职业技术学院 Accelerated wearing testing machine for spiral groove of lead screw

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