CN100492441C

CN100492441C - Composite twistless compound pendulus rod

Info

Publication number: CN100492441C
Application number: CNB200610022157XA
Authority: CN
Inventors: 梁德富; 张明宪
Original assignee: Sichuan University
Current assignee: Sichuan University
Priority date: 2006-11-01
Filing date: 2006-11-01
Publication date: 2009-05-27
Anticipated expiration: 2026-11-01
Also published as: CN1945658A

Abstract

The invention relates to a compound swing bar without twist. It takes the structure of three-lay composite sandwich, and the aperture of middle layer is less than that of outer, which thickness is 0.2~0.3 mm in control. So that the line contact between hole on the rocker and top edge of the prism is changed into the point contact on the midpoint of hole to make the rocker hang in a vertical state, eliminate twisting, save time and reduce measure error and cost.

Description

Composite twistless compound pendulus rod

One, technical field

The present invention relates to the physical pendulum in the physical experiment apparatus, the particularly a kind of physical pendulum fork that can eliminate twisting.

Two, background technology

Present known physical pendulum is made of two parts: the one, and fork, the 2nd, support, wherein the profile of fork is a block length square metal plate, the plate upper edge longitudinal centre line dozens of manhole that distributing.In the experiment be with the borehole jack of fork on the triangular prism that is laterally settled above the support, the top in fork hole then combines with the rib of triangular prism top, after the fork lower end was pulled away from the equilibrium position and discharges, fork just began swing.According to experimental principle, this swing must be the steady swing in a kind of perpendicular, will be tending towards minimum with the error of this acceleration of gravity of measuring.Yet reality is: because the thick 5mm that reaches of fork, so the fork hole is exactly the combination of two straight lines with combining of triangular prism.Because the criterion that the vertical degree of support is regulated is the level meter that relies on a bubble chamber structure on its base, then the place one's entire reliance upon accurate installation of level meter of the accuracy of this level meter, yet because the self-defect of the level meter of this structure, so can not accurately install, even accurately install, that also only reflects the levelness of base, and do not represent the levelness of triangular prism above the support, because this wherein also relates to the accuracy that combines of combining of bracket upright post and base and triangular prism and its pedestal, for above-mentioned reasons, even the bubble in the bubble chamber is placed in the middle, but do not represent triangular prism top rib to be in level, so actual effect is: the student has spent a large amount of time that bubble is transferred to the center, and the rib of triangular prism top is also out-of-level, thereby causing the top in fork hole is not desirable line contact with contacting of triangular prism top rib, but a kind of some contact.Importantly this contact point is not in the central point on top, fork hole, but being in a certain termination that push up in the hole, the fork of Xuan Guaing just can not be in vertical state in this case, so in case swing, just occur significantly twisting inevitably, finally cause bigger measuring error.

Three, summary of the invention

The purpose of this invention is to provide a kind of composite twistless compound pendulus rod, to improve the accuracy of measuring.

The object of the present invention is achieved like this: fork is made three-layer combined structure, the aperture in middle level is less than outer aperture 2～3mm, the thickness in middle level is 0.2～0.3mm, two outer field materials are all identical with thickness, every layer of hole, compound back all is in the longitudinal centre line of fork, corresponding each hole is all concentric, and the composite structure of three interlayers is that pin is compound or bonding agent is compound.

Adopt such scheme can receive following remarkable result:

1, because the fork hole has become combination bore by original cylinder hole, and the thickness in the hole, middle level that plays a crucial role in the combination bore 0.2～0.3mm only, so the hole, middle level is near a ring-type cutting edge, this ring-type cutting edge contacts with the point that just must become the hole midpoint that contacts of triangular prism top rib, the fork that hangs also just must be in a kind of vertical naturally state, in case fork begins swing, just must be in the swing in a kind of perpendicular, thereby reach a kind of perfect condition, measuring error is reduced significantly.

2, the fork of this structure has not only saved the bubble chamber and the corresponding horizontal adjusting of bracket base, also can make the machining precision of each parts of support and relaxing each other in conjunction with precision, this has not only saved a large amount of adjusting time, can also reduce the manufacturing cost of support greatly.

Four, description of drawings

Fig. 1 is the sectional view of composite twistless compound pendulus rod;

Fig. 2 is the side view of Fig. 1.

1 fork skin among the figure, 2 fork middle levels, 3 pins.

Five, embodiment

Hole, rectangular, the adjacent two hole center distance that fork is growth 60cm, wide 3cm is that the hole count of 2.2cm is 26 three-layer combined structure, the material in middle level is a stainless steel, its aperture is 9mm, the thickness in middle level is 0.2mm, two skins are the aluminium sheet that thickness is 2.4mm, its aperture is 1.2cm, the center in every layer of hole, compound back all is on the longitudinal centre line of fork, corresponding each hole is all concentric, three interlayers are by being that 6 pieces of pins of axis of symmetry are compound with fork vertical and horizontal center line, the fork two ends respectively has two pieces of pins, remaining two pieces placed in the middle.

Claims

1, a kind of composite twistless compound pendulus rod, form by fork skin, fork middle level and pin, it is characterized in that: fork is made three-layer combined structure, the aperture in middle level is less than outer aperture 2～3mm, the thickness in middle level is 0.2～0.3mm, and two outer field materials are all identical with thickness, and every layer of hole, compound back all is in the longitudinal centre line of fork, corresponding each hole is all concentric, and the composite structure of three interlayers is that pin is compound.