火工品桥带点焊专用加压机构的设计.doc

火工品桥带点焊专用加压机构的设计

摘    要

电阻焊的焊点形成的影响因素有如下三个参数：热量，时间和压力。在电阻点焊过程中如果焊接压力控制的比较合适，将得到比母材本身强度更高的焊接接头。此外，正确地施加焊接压力还可以消除焊接时的飞溅，并减少电扳的磨损和镦粗，甚至对镀锌钢板的焊接，也不会产生在多数不正常的电阻焊系统中常见的火花四溅的现象，可获得表面光洁、强度很高的焊点。这一切都说明焊接压力是焊接过程中的一个很重要的参数。因此，点焊机加压机构的重要性就不言而喻了。
本文首先介绍了国内外电阻点焊及其加压机构的研究现状，阐明了本课题研究的目的、意义。针对桥带点焊的特殊情况，以及现有脚踏式弹簧杠杆加压机构上电极行程过短，仅20mm，不能适应20mm以上深孔结构火工品的焊接；上电极导向精度过低，难以保证上电极精确对中导柱顶部中心位置的要求的问题，拟设计一种手动凸轮杠杆式加压机构，来解决以上问题。该机构通过操作手动凸轮和砝码来实现电极压力的大小调节及维持，可以保证上电极有足够的行程及导向精度。然后本文重点分析了手动凸轮杠杆式加压机构的具体工作原理，以及各个性能的实现方法。

关键词： 电阻点焊，加压机构，凸轮杠杆式
 

ABSTRACT

There are three factors: heat、time、pressure, which seriously influence the quality of welding spot in resistance welding. If the pressure can be suitably controlled in the welding process, the joint which is much stronger than primary material can be gained. In addition, when jointing, if the pressure is suitably controlled, it can reduce the splash in welding process, can reduce the abrasion of the electrode. Even when we joint the plating armor plate, there will not be much splash,  and the welding spot will be very slick and strong. All of this just wants to tell us that that welding pressure is very important in joint process. Therefore, the importance of the pressure machine does not need to say much.
The thesis first introduces actuality of resistance spot welding in-country and abroad, clarifies the aim and significance of this thesis. Be dead against the particularity of spot welding, along with some problem of spring lever pressure machine, for example: the track of the top electrode is too short, only 20mm;it can not be used when the hole is longer than 20mm. Also, the top electrode directional precision is too low, it can not make sure that the up electrode contacts exactly and correctly to the centre of the column top surface. That needs to design a new pressure machine to solve these problems. This is the manual cam lever style pressure machine. The machine use cam and poise to adjust and keep the welding pressure. The top electrode has a track which is long enough and it’s directional precision is also high. Then, this paper explains the work theory of the machine and how to achieve some function of the pressure machine.

Keywords: resistance spot welding, pressure machine, cam lever style
 

目     录
摘    要 I
ABSTRACT II
1绪论 1
1.1电阻点焊技术介绍 1
1.1.1概述 1
1.1.2点焊的原则 2
1.1.3点焊循环 2
1.1.4点焊焊接参数及相互关系 3
1.2关于点焊加压机构的研究现状 5
1.3桥带点焊专用加压机构 5
2手动凸轮杠杆式加压机构的结构原理 7
3各结构单元的分析与设计 9
3.1加压杠杆 9
3.2电极压力与砝码重量的确定 11
3.2.1当电极压力为0Kg时： 12
3.2.2当电极压力为0.5Kg时： 14
3.2.3当电极压力为1Kg时： 15
3.2.4当电极压力为1.5Kg时： 15
3.2.5电极压力与砝码到转轴01的距离的关系表 16
3.3凸轮和限位撑杆的分析与设计 16
3.3.1凸轮的分析与设计 16
3.3.2限位杆和限位撑杆的分析 21
3.4轴的分析与设计 22
3.4.1轴1的分析与设计 22
3.4.2轴2的分析与设计 23
3.4.3轴3的分析与设计 23
3.4.4座轴的分析与设计 23
总   结 24
致    谢 25
参 考 文 献 26