فن
خوبصورتی اور تندرستی
دستکاری
ثقافت اور تاریخ
تفریح
ماحول
خوراک اور مشروبات
ریورس انجینئرنگ
سائنسز
کھیل
ٹیکنالوجی
پہننے والے آلات

The Boot-Jack: Jaws That Close When You Stand on It
Tall, tight boots are hard to pull off alone. A boot-jack holds the heel of one boot while the other foot stands on it.
Henry N. DeGraw of Newburg, New York, assignor to himself and Henry Wright, received US 59,712, dated 13 November 1866, for a boot-jack whose pivoted jaws "may by the pressure of one foot on the foot-piece be made to grasp the heel of the boot on the other foot, so that said foot may be readily withdrawn therefrom." Pendants on the jaws bear on inclined bars; an india-rubber spring spreads them again when the foot lifts.
This rung works out the squeeze the wedge gives and the pull friction can hold, then builds a wooden model with elastic-band springs.
نیا سیکھنے والا
About 2 hours
ہدایات
1
1
Wedge squeeze and friction grip
Wedge squeeze and friction grip
Jupyter نوٹ بک لوڈ ہو رہی ہے…
2
2
A small push, a large squeeze
A small push, a large squeeze
The jack's inclined bars are wedges. The embedded blueprint splits stone with feathers and wedges on the same principle.
3
3
Read US 59,712
Read US 59,712
"This invention relates to a new and improved boot-jack of that class which are provided with movable or pivoted jaws; and it consists in a novel and improved manner of applying the jaws to the foot-piece and arranging certain parts therewith, whereby the jaws may by the pressure of one foot on the foot-piece be made to grasp the heel of the boot on the other foot, so that said foot may be readily withdrawn therefrom."
"The device is used by placing the heel of the boot from which the foot is to be withdrawn between the outer curved parts of the jaws F F, and placing the other foot on the foot-piece A, and pressing upon the latter in a downward and forward direction, so as to force down the frame D and the foot or toe end of the foot piece A, and in consequence of the pendants H of the jaws bearing against the oblique or inclined bars d d of the frame E, the two jaws F F will be pressed toward each other and made to grasp firmly the heel of the boot, so that the foot can be readily drawn from it. On taking the foot from the foot-piece the spring G will distend the jaws F F".
4
4
Build a gripping jack
Build a gripping jack
Cut a pine board about 35 cm long as the foot-piece and screw a short block under its middle so the toe end rises. From plywood cut two curved jaws that meet around a heel; pivot each on a screw under the toe end. Glue two strips in a V under the front, so pressing the board down pushes the jaws' tails along the strips and closes the jaws. Stretch elastic bands between the jaws to spread them.
Try it with a boot: heel in the jaws, other foot on the board. Then hang a bag of known weight from a boot held in the jaws while someone stands on it, adding weight until it slips.
اس مرحلے کے لیے مواد:
چیڑ کا تختہ1 ٹکڑا
پلائی ووڈ کی چادر1 ٹکڑا
الاسٹک پٹی4 ٹکڑے
لکڑی کے پیچ1 ٹکڑادرکار اوزار:
گھما دار آری
بے تار مشق
مشقوں کا سیٹ
پیچ کس سیٹ
بوٹ اتارنے کا تختہ5
5
A boot-jack that slips or will not let go
A boot-jack that slips or will not let go
Boot-jack troubleshooting.
Flow
Loading...
6
6
History and honest limits
History and honest limits
**Henry N. DeGraw** of Newburg, New York, assignor to himself and Henry Wright, received US 59,712, dated 13 November 1866 (no filing date is printed on patents of that period). He notes "quite a large number having been recently manufactured and sold."
**Honest limits.** The patent gives no angles or forces. Body mass, the share pressed forward, bar angles, friction and the pull a boot needs are examples.
مواد
4- 1 ٹکڑاپلیس ہولڈر
- 1 ٹکڑاپلیس ہولڈر
- الاسٹک پٹی10% کمیشن4 ٹکڑےپلیس ہولڈر
- 1 ٹکڑاپلیس ہولڈر
درکار اوزار
5- پلیس ہولڈر
- 1 vendor sell this, none ship to you yetپلیس ہولڈر
- پلیس ہولڈر
- پلیس ہولڈر
- پلیس ہولڈر
متعلقہ بلیو پرنٹ
یہ بلیو پرنٹ علم بانٹتے ہیں — تکنیک، مواد یا اصول
CC0 پبلک ڈومین
یہ بلیو پرنٹ CC0 کے تحت جاری کیا گیا ہے۔ آپ اجازت لیے بغیر اس کام کو نقل، ترمیم، تقسیم اور کسی بھی مقصد کے لیے استعمال کرنے کے لیے آزاد ہیں۔
میکر کی حمایت کریں ان کے بلیو پرنٹ کے ذریعے پروڈکٹس خرید کر جہاں وہ میکر کمیشن وینڈرز کی طرف سے مقرر، کماتے ہیں، یا اس بلیو پرنٹ کی نئی تکرار بنائیں اور آمدنی شیئر کرنے کے لیے اسے اپنے بلیو پرنٹ میں کنکشن کے طور پر شامل کریں۔


