How Do You Calculate an Extension Spring's Rate?
You've chosen a spring, but it's too stiff or too weak. Uyu mutambo wekufungidzira unotungamira kusashanda zvakanaka, chigadzirwa kukundikana, uye kugadzirisazve kunodhura, kumisa purojekiti yako iwe uchitsvaga mhinduro.
The spring rate is calculated using a formula that considers the material's shear modulus (G), waya dhayamita[^ 1] (d), zvinoreva coil dhayamita[^ 2] (D), uye huwandu hwekoni rinoshanda (Kare). These physical properties directly determine the spring's stiffness.
I've seen countless projects get delayed simply because the spring rate was an afterthought. Injiniya anozogadzira gungano rose obva aedza kutsvaga chitubu chemasheya chinokodzera, kungoona chete hapana ane mwero chaiwo. PaLINSPRING, tinogara tichitanga nesimba rinodiwa. Nokuverenga zvinodiwa spring rate[^3] chekutanga, isu tinogona kugadzira chitubu chinopa iyo chaiyo kuita inodiwa, kuchengetedza vatengi vedu nguva, mari, uye kushushikana kwakawanda. Let's look at how this calculation is done.
Chii Chikuru Formula yeKuverengera Chirimo Rate?
Unoona spring rate[^3] formula, uye zvinoratidzika zvinotyisa. You're worried that if you misinterpret just one of the variables, kuverenga kwako kwese kunenge kusina kururama, zvichitungamira kune zvakaraswa prototypes.
Iyo yekutanga formula ndeye: *k = (G d⁴) / (8 D³ Kare)**. Zvingaita sezvakaoma, but it's just a combination of the spring's material (G), waya yayo (d), geometry yake (D), uye nhamba yayo yemakoiri (Kare).
Ndinowanzo taurira mainjiniya matsva kuchikwata changu kuti asatye neiyi fomula. Zvifunge seresipi. Zvisungo ndizvo zvinhu zvako, waya, uye zviyero zvecoil. Iyo formula ndiyo seti yemirairo inokuudza kuti izvo zvinongedzo zvichabatana sei kuburitsa yekupedzisira "flavor," which is your spring's stiffness. The most important thing I've learned is how powerful the waya dhayamita[^ 1] (d) ndizvo. Because it's raised to the fourth power, kunyangwe shanduko diki muhukuru hwewaya ichave nemhedzisiro yakakura pachiyero chekupedzisira chechirimo. It's the most critical ingredient in the entire recipe.
Kunzwisisa Imwe neimwe Yakasiyana muFormula
Chikamu chimwe nechimwe chefomura chinomiririra chimiro chakasiyana chechirimo. Kuwana imwe neimwe yakakodzera kwakakosha kune mhedzisiro chaiyo. Zvinhu zviviri zvinonyanya kupesvedzera dhayamita yewaya uye dhayamita yekoiri.
- Modulus yeRigidity (G): Iyi ipfuma yezvinhu pachayo, inomiririra kuramba kwayo kumonyoroka. Zvesimbi, it's around 11.5 miriyoni psi.
- Waya diamita (d): Ukobvu hwewaya yechitubu. Izvi zvine mhedzisiro yakakura pachiyero.
- Kureva Coil Diameter (D): Avhareji yedhayamita yemakoiri, yakaverengerwa seOuter Diameter minus one Wire Diameter.
- Active Coils (Kare): Nhamba yemakoiri mumuviri wechitubu ayo akasununguka kutambanudza.
| Variable | Zita | Tsanangudzo |
|---|---|---|
| k | Spring Rate | The spring's stiffness, kuyerwa nesimba pachikamu cheurefu (e.e., lb/in). |
| G | Modulus yeRigidity[^4] | Chinhu chenyama chinogara chiripo kune alloy yakapihwa. |
| d | Waya diamita | Kuwanda kwewaya yakashandiswa kugadzira chitubu. |
| D | Kureva Coil Diameter | Ivhareji yepakati kubva pakati petambo kune rumwe rutivi kusvika kune rumwe. |
| Kare | Active Coils | Huwandu hwemakoiri anochengeta uye anoburitsa simba. |
Iwe Unonyatsoziva Sei Nhamba Yemakoiri Anoshanda?
Wakaverenga huwandu hwemakoiri kubva kumagumo kusvika kumagumo. Asi kana iwe ukashandisa iyo nhamba mune fomula, yako yakaverengerwa spring rate[^3] doesn't match the test data.
Uku kukanganisa kwakajairika. Nhamba yemakoiri anoshanda (Kare) inongosanganisira makoiri mumutumbi mukuru wechirimo. The end hooks or loops are not considered active because they do not contribute to the spring's deflection.
Ndakamboshanda nemutengi aigadzira chitubu chembwa inodzoreka. Vakaita macalculation avo vakatitumira dhirowa. Mari yechirimo yavakataura yaive yakawanda, yakaderera zvakanyanya pane izvo zvakafanotaurwa neformula yekugadzirwa kwavo. Ndakavadaidza, uye takafamba mukuverenga pamwe chete. Zvakaratidza kuti vakanga vabatanidza makoiri aiumba hoko dzekupedzisira mukati mavo "Active Coils[^5]" count. Hoko dziripo kuendesa mutoro, kwete kutambanudza. Takambogadzirisa nhamba imwe iya, masvomhu edu aienderana zvakakwana. Takazokwanisa kugadzirisa dhizaini kuti tivape yakatsetseka, dhonza zvinyoro nyoro zvavaida tambo.
Body Coils vs. End Loops
Musiyano uripo pakati pemakoiri anoshanda neasingashande unobva pabasa rawo. Makoiri chete akasununguka kumonyorora pasi pemutoro anoonekwa seanoshanda.
- Body Coils: Aya ndiwo machira ekutanga anoumba kureba kwechirimo. Paunokweva pachitubu, makoiri aya haana kumonyoroka zvishoma, izvo zvinogadzira kuwedzera. Naizvozvo, vose vari kushanda.
- End Hooks/Loops: Aya anoumbwa kubva kune yekupedzisira coil kana maviri pamagumo ega ega. Basa ravo nderekubatanidza chitubu pagungano rako. They transfer force but are not designed to flex or contribute to the spring's travel. Vanonzi “vakafa" kana mukatiActive Coils[^5]. Saka, nokuda kwechitubu chekuwedzera, Na = nhamba yemakoiri mumuviri.
| Spring Component | Function | Active? |
|---|---|---|
| Body Coils | Chengetedza uye sunungura simba nekutsausa. | Ehe |
| End Hooks/Loops | Tumira mutoro kugungano. | Aihwa |
Unogona Sei Kuverengera Chiyero kubva kune Yenyama Chitubu?
Une chitubu, but you don't know its specifications. Iwe unofanirwa kuwana chiyero chayo pasina kuve nedhizaini yedhizaini kana kuziva zvinhu, kuita kuti zvisakwanise kushandisa formula.
Iwe unogona kuona chiyero uchiyedza neyakapusa-mapoinzi bvunzo. Pima simba rinodiwa kutambanudza chitubu kusvika paurefu huviri hwakasiyana. The the spring rate[^3] ndiyo shanduko yesimba yakakamurwa nekushanduka kwehurefu.
Ichi chinhu chatinoita mune yedu yemhando lab mazuva ese. It's the most practical and reliable way to verify a spring's rate. Ndakanga ndine mutengi aiedza kutsiva chitubu chakaputsika muchidimbu chemidziyo yekare yepurazi. Mugadziri wepakutanga akanga asisina basa, uye pakanga pasina mifananidzo. Akatitumira chitubu chakaputsika. We couldn't use the design formula because we weren't 100% chokwadi chezvinyorwa. Pane kudaro, tinoiisa paload tester yedu. Takayera mutoro pane imwe inch yekufamba uye pamasendimita maviri ekufamba. Nokubvisa masimba nehurefu, takaverenga chiyero chaicho chechirimo. Kubva ipapo, taigona kugadzira chinotsiva chakakwana.
Iyo Yemapoindi Maviri Ekuyedza Nzira
Iyi nzira yakatwasuka uye inoda chete maturusi ekuyera ekutanga.
- Measure Point 1: Tambanudza chitubu kune hurefu hunozivikanwa (L1) uye nyora simba racho (F1).
- Measure Point 2: Tambanudza chitubu mberi kune yechipiri inozivikanwa kureba (L2) uye nyora simba racho (F2).
- Verenga Rate (k): Shandisa fomula: k = (F2 - F1) / (L2 - L1).
Semuyenzaniso, kana chitubu chinoratidza mutoro we 20 lbs uye 4 inchi uye 30 lbs uye 6 inches:
- Shanduko muSimba = 30 lbs - 20 lbs = 10 lbs
- Shanduko muUrefu = 6 inches - 4 inches = 2 inches
- Spring Rate (k) = 10 lbs / 2 inches = 5 lbs/inch
| Danho | Chiito | Muenzaniso Kukosha |
|---|---|---|
| 1. Kuverenga Kwekutanga | Record Force (F1) pa Length (L1). | 20 lbs uye 4 inches. |
| 2. Kuverenga kwechipiri | Record Force (F2) pa Length (L2). | 30 lbs uye 6 inches. |
| 3. Calculation | (F2 - F1) / (L2 - L1) |
(30-20)/(6-4) = 5 lbs/in |
Mhedziso
You can calculate an extension spring's rate theoretically using its physical dimensions and material, kana kuti nokuiedza. Nzira mbiri idzi dzakakosha pakugadzira dhizaini nekusimbisa.
[^ 1]: Dzidza kuti waya dhayamita inokanganisa sei zvakanyanya kuoma kwechirimo uye kushanda kwese.
[^ 2]: Ziva kukosha kweiyo dhayamita yecoil mukuona hunhu hwechirimo uye kuita.
[^3]: Kunzwisisa chiyero chechirimo formula kwakakosha pakugadzira zvitubu zvinoshanda zvinosangana nezvinodiwa zvekuita.
[^4]: Wana nzwisiso muModulus yeRigidity uye basa rayo mukusarudzwa kwezvinhu zvezvitubu.
[^5]: Kunzwisisa macoil anoshanda kwakakosha pakuverenga kwakaringana uye dhizaini inoshanda yematsutso.