CN103308251A - Method for eliminating reverse load phenomenon, device and application thereof - Google Patents

Abstract

The invention discloses a method for eliminating the reverse load phenomenon, a device and an application thereof, belonging to the technical field of force metrology and aiming at solving the problem of resource waste in the prior art and eliminating the reverse load phenomenon in the process of force metrology. The device comprises a hanging rod and a clamping device, wherein the hanging rod consists of at least two hinged rod pieces; the hanging rod is hung on a bearing beam by a loose-joint hinge; the clamping device is positioned under the last hinge of the hanging rod; and before a weight is changed, the hanging rod is clamped by the clamping device. The method for eliminating the reverse load phenomenon on the basis of the device for eliminating the reverse load phenomenon comprises the following steps of clamping the hanging rod, changing the weight, loosening the hanging rod and starting to measure. The invention has the advantages that the hanging rod is clamped by the clamping device before the weight is changed, so that the purpose of eliminating the reverse load phenomenon in the process of changing the weight is achieved, the quantity of the weights is reduced, and resource is saved.

Description

A kind of method, device and application thereof of eliminating contrary load phenomenon

Technical field

The invention belongs to power value field of measuring techniques, be specifically related to a kind of method, device and application thereof of eliminating contrary load phenomenon.

Background technology

Utilizing the counterweight imposed load or counterweight is being amplified in the load mode of after-applied load, adopt the counterweight switching method, use two gravity counterweights of 100N, 200N, test specimen is applied the power load, then can obtain 100N, 200N, three grades of load of (100+200) N.Wherein 200N load is at first the 100N counterweight that has applied to be taken off, and then puts the counterweight of 200N.The power that acts in this journey on the test specimen at first is reduced to 0, and then is increased to 200N, this in adding the process of load, and the phenomenon that the power on the test specimen has reduced i.e. so-called " contrary load ".This phenomenon is unallowed in many occasions, as in power value metrology applications field, can cause measuring the result against the load phenomenon and have certain inaccuracy.Because this contrary load problem is not resolved, so utilizing the counterweight imposed load or Weight gravity amplified in the load mode of after-applied load, all adopt and do not have the loading of exchange counterweight, need reach the purpose of increase power value scope with the method that increases counterweight quantity, this kind method counterweight quantity demand is many, can cause the waste of resource.

Summary of the invention

The objective of the invention is to propose a kind of method, device and application thereof of eliminating contrary load phenomenon, solve the problem that there is the wasting of resources in prior art, eliminate the contrary load phenomenon that in power value metering process, exists.

For achieving the above object, a kind of device of eliminating contrary load phenomenon of the present invention comprises hangs bar and clamp device, the described bar of hanging is made up of the rod member of two hinges at least, the described bar of hanging hangs on the described carrier bar by a loose joint hinge, implement to clamp to hanging bar by described clamp device before the exchange counterweight, described clamp device top has two hinges at least, and near last hinge of top, described clamp device clamp described hang bar after, applying or unloading of counterweight there is not potent influence to clamp device with the bar of hanging on top.

Described hinge is spherical hinge or Hooke's hinge.

Described clamp device is fixed on the frame, and the described bar bottom of hanging is provided with pallet, adds release mechanism by described counterweight the gravity counterweight is placed on the pallet of hanging bar, or take off from hanging the lever bracket dish.

Described clamp device comprises motor, leading screw, nut A, nut B, slide block A, slide block B, clamp A, clamp B, line slideway and guide rail fixed plate, the slide rail of described line slideway is fixed on the described guide rail fixed plate by screw, slide block A on the slide rail is positioned at the slide rail left side and is connected by screw with clamp A, slide block B on the slide rail is positioned at the slide rail right side and clamp B is connected by screw, described nut A cooperates the formation screw pair with the left side of described leading screw, described nut B cooperates the formation screw pair with the right side of described leading screw, the lead of described two pairs of screw pairs is identical with a number, but rotation direction is opposite, described clamp A is fixed on the described nut A, described clamp B is fixed on the described nut B, by described driven by motor leading screw rotation, and then drive nut A and nut B motion, realize the move toward one another of clamp A and clamp B, the end that described clamp A is relative with described clamp B all has the V-type groove, and described clamp A is to be cooperated with the described bar of hanging by described V-type groove with described clamp B realizing hanging in the tight process of bar cramp.

Described driven by motor leading screw rotation is specially: motor drives the leading screw rotation by the thick stick rotation of band driving-belt movable wire or by shaft coupling.

May further comprise the steps based on a kind of contrary method of loading phenomenon of elimination of eliminating the device of contrary load phenomenon:

Step 1: hang bar by the clamp device clamping;

Step 2: exchange counterweight;

Step 3: clamp device unclamps hangs bar;

Step 4: treat to begin metering behind the monolithic stability.

A kind of another kind of eliminating the device of contrary load phenomenon is applied as the application on the lever force standard machines, carrier bar is born by the lever crossbeam of lever force standard machines, and clamp device should be at more than 50 times of lever force standard machines main frame rigidity in clamping force vertical direction and frame contact stiffness.

Beneficial effect of the present invention is: compared with prior art, a kind of method, device and application thereof of eliminating contrary load phenomenon of the present invention, utilizing the counterweight imposed load or Weight gravity is being amplified in the load mode application of after-applied load, hanging before bar applies or unload the gravity counterweight, at first enabling clamp device, will to hang bar cramp tight, make that act on the clamped position downside subsequently hangs acting force on the bar, to be passed on the frame by clamp system, and it is constant to hang the acting force of bar epimere partial action on carrier bar; Therefore, when under this clamp device clamping force effect, carrying out the counterweight exchange, with can not occur adding test specimen institute stress value in the load process reduces or the unloaded process in the contrary load phenomenon that increases of test specimen institute stress value, reach the purpose of eliminating contrary load phenomenon, and reduce counterweight quantity, save resource.

Description of drawings

Fig. 1 is a kind of fundamental diagram of eliminating the device of contrary load phenomenon of the present invention;

Fig. 2 is the clamp device structural drawing in a kind of device of eliminating contrary load phenomenon of the present invention;

Fig. 3 is the fundamental diagram of the clamp device in a kind of device of eliminating contrary load phenomenon of the present invention;

Fig. 4 is the clamp device wiring layout in a kind of device of eliminating contrary load phenomenon of the present invention;

Fig. 5 is a kind of process flow diagram of eliminating the method for contrary load phenomenon of the present invention;

Fig. 6 is the schematic diagram of clamp device of the present invention when hanging stick force value active line and do not overlap;

Fig. 7 is the clamping mechanical model of the clamp device in a kind of device of eliminating contrary load phenomenon of the present invention;

Fig. 8 is power value output wave cardon of the present invention;

Fig. 9 is the application principle figure of the present invention on the lever force standard machines;

Wherein: 1, hang bar, 2, motor, 3, leading screw, 4, nut A, 5, nut B, 6, slide block A, 7, slide block B, 8, clamp A, 9, clamp B, 10, line slideway, 11, guide rail fixed plate, 12, carrier bar, 13, frame, 14, the gravity counterweight, 15, pallet, 16, counterweight adds release mechanism, and 17, lever crossbeam.

Embodiment

Below in conjunction with accompanying drawing embodiments of the present invention are described further.

Referring to accompanying drawing 1, a kind of device of eliminating contrary load phenomenon of the present invention comprises hangs bar 1 and clamp device, the described bar 1 of hanging is made up of the rod member of two hinges at least, described hinge can be spherical hinge, it also can be Hooke's hinge, the described bar 1 of hanging hangs on the described carrier bar 12 by a described loose joint hinge, and described clamp device is positioned at described below of hanging last hinge of bar 1, implements to clamp to hanging bar 1 by described clamp device before the replacing counterweight.

Described clamp device is fixed on the frame 13, and described bar 1 bottom of hanging is provided with pallet 15, adds release mechanism 16 by described counterweight gravity counterweight 14 is placed on the pallet 15 of hanging bar 1, or take off from pallet 15.

Referring to accompanying drawing 2, accompanying drawing 3 and accompanying drawing 4, described clamp device comprises motor 2, leading screw 3, nut A4, nut B5, slide block A6, slide block B 7, clamp A8, clamp B9, line slideway 10 and guide rail fixed plate 11, the slide rail of described line slideway 10 is fixed on the described guide rail fixed plate 11 by screw, slide block A6 on the slide rail is positioned at the slide rail left side and is connected by screw with clamp A8, slide block B 7 on the slide rail is positioned at the slide rail right side and clamp B9 is connected by screw, described nut A4 cooperates formation worm drive pair with the left side of described leading screw 3, described nut B5 cooperates formation worm drive pair with the right side of described leading screw 3, the lead of described two pairs of worm drive pairs is identical with a number, but rotation direction is opposite, described clamp A8 is fixed on the described nut A4, described clamp B9 is fixed on the described nut B5, drive leading screw 3 rotations by described motor 2, and then drive nut A4 and nut B5 motion, realize the move toward one another of clamp A8 and clamp B9; Described clamp A8 has the V-type groove with the relative end of described clamp B9; Described clamp A8 is to be cooperated with the described bar 1 of hanging by described V-type groove with described clamp B9 in realizing the process of hanging bar 1 clamping.

Described motor 2 drives leading screw 3 rotations and is specially motor 2 by thick stick 3 rotations of band driving-belt movable wire or by the shaft coupling driven rotary.

Referring to accompanying drawing 5, comprise following performing step based on a kind of contrary method of loading phenomenon of elimination of eliminating the device of contrary load phenomenon:

Step 1: hang bar 1 by the clamp device clamping;

Step 2: exchange counterweight;

Step 3: clamp device unclamps hangs bar 1;

Step 4: treat to begin metering behind the monolithic stability.

Referring to accompanying drawing 6, for reducing error, to hang bar 1 and be made into the rod member that two sections hinged bars constitute, clamp device is arranged at the downside of epimere bar lower end hinge.Be considered as plane force system with hanging the acting force that bar 1 is subjected to.If clamp device slide block chuck centering position does not overlap with hanging bar 1 power value active line, its angle is θ, and hanging bar 1 with epimere is analytic target, omits the hinge friction, has following formula to set up according to the statical equilibrium principle:

Tsinθ=N （1）

Tcosθ=W （2）

Wherein T hangs the axial force that bar 1 is subjected to, and W acts on the acting force of hanging bar 1 hypomere, and N is that clamp device is to hanging the clamping force that bar 1 applies.

The acting force that acts on the upper end hinge according to the force analysis of rod member as can be known still is W in vertical direction, namely because clamp device makes and hangs bar 1 disalignment, will can not influence lever loading device output action power size and Orientation.

In order to ensure fixture block with hang bar 1 and keep one, obviously acting on the variation power of hanging on the bar 1 should be less than because the friction force that clamping produces.Can under the situation of known friction factor, calculate the size of required clamping force N accordingly.Obvious, clamping force only need guarantee under the situation of the power of changing, and hangs bar 1 and keeps one to get final product with clamp device, and need not bigger clamping force.

For lever loading device, the suffered acting force of member is only influential to machine output action power in vertical direction, so after only considering that bar 1 is hung in the clamp device clamping, power is applied on fixed rack and the frame 13, and their distortion is to the influence of machine power output.If they all are the linear elasticity members, be reduced to spring together with the member contact interface, the clamping section virial is learned model simplification referring to accompanying drawing 7.Wherein

N ₁, N ₂The clamping normal pressure that clamp device provides;

F ₁, F ₂Clamp the normal pressure lower fixture to hanging the friction force of bar;

k ₁, k ₂Elasticity coefficient for clamp device and servicing unit overall simplification thereof;

Q ₁, Q ₂For clamp device acts on support reaction on the frame 13;

μ, chuck and the friction factor of hanging the clamping position.

Obviously, after clamp device clamps, when acting on the acting force variation of hanging on the bar 1, because spring k ₁, k ₂Reason, hang bar 1 and can produce displacement in vertical direction, be made as △ y, its size meets following relation:

(k ₁+k ₂)·△y=W （3）

$\mathrm{\Δy}=\frac{W}{k_1+k_2}---\left(4\right)$

Wherein W is that the power value of hanging on the bar 1 changes.

Because the appearance of △ y will inevitably cause the imbalance of lever, causes the output pulsation of power value.Referring to accompanying drawing 8, suppose lever output load end because the displacement that elastic deformation causes is △ y ₁, lever long arm end length is L, and lever short arm end length is l, and output terminal load carrier and test specimen etc. are reduced to the linear elasticity element, and rigidity is k ₃, the output load p be changed to △ P, then have:

△P=k ₃·△y ₁ （5）

Again because:

$\mathrm{\&Delta;}{\mathrm{<figure-callout\; id="1"\; label="y"\; filenames="HDA00003172810900011.png,HDA00003172810900021.png"\; state="\{\{state\}\}">y</figure-callout>}}_1=\frac{l}{L}\&CenterDot;\mathrm{\&Delta;y}---\left(6\right)$

Thereby:

$\mathrm{\&Delta;P}={\mathrm{<figure-callout\; id="3"\; label="k"\; filenames="HDA00003172810900012.png,HDA00003172810900021.png"\; state="\{\{state\}\}">k</figure-callout>}}_3\&CenterDot;\mathrm{\&Delta;}{\mathrm{<figure-callout\; id="1"\; label="y"\; filenames="HDA00003172810900011.png,HDA00003172810900021.png"\; state="\{\{state\}\}">y</figure-callout>}}_1={\mathrm{<figure-callout\; id="3"\; label="k"\; filenames="HDA00003172810900012.png,HDA00003172810900021.png"\; state="\{\{state\}\}">k</figure-callout>}}_3\&CenterDot;\frac{l}{L}\&CenterDot;\mathrm{\&Delta;y}={\mathrm{<figure-callout\; id="3"\; label="k"\; filenames="HDA00003172810900012.png,HDA00003172810900021.png"\; state="\{\{state\}\}">k</figure-callout>}}_3\&CenterDot;\frac{l}{L}\&CenterDot;\frac{\mathrm{<figure-callout\; id="1"\; label="W\; k"\; filenames="HDA00003172810900011.png,HDA00003172810900021.png"\; state="\{\{state\}\}">W</figure-callout>}}{k_{}}---\left(7\right)$

If establish when the level load be Pn, its corresponding Weight gravity is W ₁, then change relatively

$\mathrm{\&delta;}=\frac{\mathrm{\&Delta;P}}{P_n}=\frac{{\mathrm{<figure-callout\; id="3"\; label="k"\; filenames="HDA00003172810900012.png,HDA00003172810900021.png"\; state="\{\{state\}\}">k</figure-callout>}}_3\&CenterDot;\frac{l}{L}\&CenterDot;\frac{\mathrm{<figure-callout\; id="1"\; label="W\; k"\; filenames="HDA00003172810900011.png,HDA00003172810900021.png"\; state="\{\{state\}\}">W</figure-callout>}}{k_{}}}{{\mathrm{<figure-callout\; id="1"\; label="W"\; filenames="HDA00003172810900011.png,HDA00003172810900021.png"\; state="\{\{state\}\}">W</figure-callout>}}_1\&CenterDot;\frac{l}{L}}=\frac{k_3}{{\mathrm{<figure-callout\; id="1"\; label="k"\; filenames="HDA00003172810900011.png,HDA00003172810900021.png"\; state="\{\{state\}\}">k</figure-callout>}}_1+{\mathrm{<figure-callout\; id="2"\; label="k"\; filenames="HDA00003172810900021.png"\; state="\{\{state\}\}">k</figure-callout>}}_2}\&CenterDot;\frac{W}{W_1}---\left(8\right)$

After horizontal sliding clamped as can be known according to above derivation, it was relevant with the gravity and the system stiffness that exchange counterweight to carry out the power value fluctuation that the counterweight exchange causes.The rigidity of clamp device fixed rack and frame 13 is more good, more big when the Weight gravity value of level power value correspondence, that lever system power output value part rigidity is more little, Weight gravity changes more little then power value fluctuation is more little.Consider extreme case, W=W ₁, then have:

${\mathrm{\&delta;}}_{\max }=\frac{k_3}{{\mathrm{<figure-callout\; id="1"\; label="k"\; filenames="HDA00003172810900011.png,HDA00003172810900021.png"\; state="\{\{state\}\}">k</figure-callout>}}_1+k_2}---\left(9\right)$

Be the ratio that both sides rigidity is depended in the fluctuation of power value.Obviously have the fixed bearing rigidity of clamp device should be as far as possible greater than loading the output rigidity.

Referring to 9, these apparatus and method are applied on the lever force standard machines, and the carrier bar 12 among the present invention is born by the lever crossbeam of lever force standard machines.

Claims (7)

1. the device of the contrary load of elimination phenomenon, it is characterized in that, comprise and hang bar (1) and clamp device, the described bar (1) of hanging is made up of the rod member of two hinges at least, the described bar (1) of hanging hangs on the described carrier bar (12) by a loose joint hinge, implement to clamp to hanging bar (1) by described clamp device before the exchange counterweight, described clamp device top has two hinges at least, and near last hinge of top, described clamp device clamp described hang bar (1) after, applying or unloading of counterweight there is not potent influence to clamp device with the bar of hanging on top.

2. a kind of device of eliminating contrary load phenomenon according to claim 1, it is characterized in that, described clamp device is fixed on the frame (13), described bar (1) bottom of hanging is provided with pallet (15), add release mechanism (16) by described counterweight gravity counterweight (14) is placed on the pallet (15) of hanging bar (1), or take off from pallet (15).

3. a kind of device of eliminating contrary load phenomenon according to claim 1, it is characterized in that, described clamp device comprises motor (2), leading screw (3), nut A(4), nut B(5), slide block A(6), slide block B (7), clamp A(8), clamp B(9), line slideway (10) and guide rail fixed plate (11), the slide rail of described line slideway (10) is fixed on the described guide rail fixed plate (11) by screw, slide block A(6 on the slide rail) be positioned at slide rail left side and clamp A(8) be connected by screw, slide block B on the slide rail (7) is positioned at slide rail right side and clamp B(9) be connected by screw, described nut A(4) cooperates formation worm drive pair with the left side of described leading screw (3), described nut B(5) cooperates formation worm drive pair with the right side of described leading screw (3), the lead of described two pairs of worm drive pairs is identical with a number, but rotation direction is opposite; Described clamp A(8) be fixed on described nut A(4) on, described clamp B(9) be fixed on described nut B(5) on, drive leading screw (3) rotation by described motor (2), and then drive nut A(4) and nut B(5) motion, realization clamp A(8) and clamp B(9) move toward one another; Described clamp A(8) with described clamp B(9) relative end has the V-type groove; Described clamp A(8) with described clamp B(9) hang V-type groove described in bar (1) process in clamping and cooperate with the described bar (1) of hanging.

4. a kind of device of eliminating contrary load phenomenon according to claim 3 is characterized in that, described motor (2) drives leading screw (3) rotation and is specially motor (2) by band driving-belt movable wire thick stick (3) rotation or by the shaft coupling driven rotary.

5. a kind of device of eliminating contrary load phenomenon according to claim 1 is characterized in that described hinge is spherical hinge or Hooke's hinge.

6. based on the method for the contrary load of the elimination phenomenon of the described a kind of device of eliminating contrary load phenomenon of claim 1, it is characterized in that, may further comprise the steps:

Step 1: hang bar (1) by the clamp device clamping;

Step 2: exchange counterweight;

Step 3: clamp device unclamps hangs bar (1);

Step 4: treat to begin metering behind the monolithic stability.

7. a kind of device of eliminating contrary load phenomenon according to claim 1, it is characterized in that, a kind of another kind of eliminating the device of contrary load phenomenon is applied as the application on the lever force standard machines, carrier bar (12) is born by the lever crossbeam (17) of lever force standard machines, clamp device at clamping force vertical direction and frame (13) contact stiffness greater than lever force standard machines main frame rigidity.

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