agid])) { foreach ($g_flag_thread[$flagid] as &$val) { flag_thread_filter($val); } flag_thread_set($flagid, $g_flag_thread[$flagid]); } } return $g_flag_thread[$flagid]; } // 设置缓存 $key = flagid / $val = flagid下tid数组 function flag_thread_set($key, $val) { global $g_flag_thread; FALSE === $g_flag_thread and $g_flag_thread = website_get('flag_thread'); empty($g_flag_thread) and $g_flag_thread = array(); $g_flag_thread[$key] = $val; return website_set('flag_thread', $g_flag_thread); } // 删除flag下tid缓存 function flag_thread_delete_cache($flagid) { global $g_flag_thread; FALSE === $g_flag_thread and $g_flag_thread = website_get('flag_thread'); empty($g_flag_thread) and $g_flag_thread = array(); if (isset($g_flag_thread[$flagid])) { unset($g_flag_thread[$flagid]); website_set('flag_thread', $g_flag_thread); } return TRUE; } // Delete by tid / 通过tid删除flag下的主题和对应flagid缓存 function flag_thread_delete_by_tid($tid) { global $g_flag_thread; FALSE === $g_flag_thread and $g_flag_thread = website_get('flag_thread'); if (empty($g_flag_thread)) { $g_flag_thread = array(); } else { $thread = well_thread_read_cache($tid); $arrlist = flag_thread_find($tid, 1, $thread['flags']); $flagarr = $ids = array(); foreach ($arrlist as $val) { $flagarr[] = $val['flagid']; $ids[] = $val['id']; if (isset($g_flag_thread[$val['flagid']])) unset($g_flag_thread[$val['flagid']]); } website_set('flag_thread', $g_flag_thread); // 主键更新 flag_update($flagarr, array('count-' => 1)); // 主键删除 flag_thread_delete($ids); } return TRUE; } // 主键删除 通过$flagid删除flag下的主题和对应flagid缓存 function flag_thread_delete_by_flagid($flagid) { global $g_flag_thread; FALSE === $g_flag_thread and $g_flag_thread = website_get('flag_thread'); $read = flag_read_cache($flagid); if (empty($read)) return TRUE; $arrlist = flag_thread_find_by_flagid($flagid, 1, $read['count']); if (empty($arrlist)) return TRUE; $flagarr = $ids = array(); $n = 0; foreach ($arrlist as $val) { ++$n; $flagarr[] = $val['flagid']; $ids[] = $val['id']; if (isset($g_flag_thread[$flagid])) unset($g_flag_thread[$flagid]); } website_set('flag_thread', $g_flag_thread); // 主键更新 flag_update($flagarr, array('count-' => $n)); // 主键删除 $r = flag_thread_delete($ids); return $r; } ?>组保留的标签 余下为需要删除的标签 unset($oldtag[$key]); } } } if (!empty($oldtag)) { $tagids = array(); foreach ($oldtag as $tagid => $tagname) { $tagids[] = $tagid; } well_oldtag_delete($tagids, $tid); } $r = well_tag_process($tid, $fid, $create_tag, $tagarr); return $r; } // 删除标签和绑定的主题 function well_oldtag_delete($tagids, $tid) { $pagesize = count($tagids); $arrlist = well_tag_find_by_tagids($tagids, 1, $pagesize); $delete_tagids = array(); // 删除 $tagids = array(); $n = 0; foreach ($arrlist as $val) { ++$n; if (1 == $val['count']) { // 只有一个主题 $delete_tagids[] = $val['tagid']; } else { $tagids[] = $val['tagid']; } } !empty($delete_tagids) and well_tag_delete($delete_tagids); $arlist = well_tag_thread_find_by_tid($tid, 1, $n); if ($arlist) { $ids = array(); foreach ($arlist as $val) $ids[] = $val['id']; well_tag_thread_delete($ids); } !empty($tagids) and well_tag_update($tagids, array('count-' => 1)); } // 标签数据处理 $arr=新提交的数组 $tagarr=保留的旧标签 function well_tag_process($tid, $fid, $new_tags = array(), $tagarr = array()) { if (empty($tid)) return ''; // 新标签处理入库 if ($new_tags) { $threadarr = array(); $tagids = array(); $i = 0; $size = 5; $n = count($tagarr); $n = $n > $size ? $size : $size - $n; foreach ($new_tags as $name) { ++$i; $name = trim($name); $name = stripslashes($name); $name = strip_tags($name); $name = str_replace(array(' ', '#', "@", "$", "%", "^", '&', '·', '<', '>', '；', '`', '~', '!', '￥', '……', ';', '?', '？', '-', '—', '_', '=', '+', '.', '{', '}', '|', ':', '：', '、', '/', '。', '[', ']', '【', '】', '‘', ' ', ' ', ' ', ' ', ' '), '', $name); $name = htmlspecialchars($name, ENT_QUOTES); if ($name && $i <= $n) { // 查询标签 $read = well_tag_read_name($name); if ($read) { // 存在 count+1 $tagids[] = $read['tagid']; } else { // 入库 $arr = array('name' => $name, 'count' => 1); $tagid = well_tag_create($arr); FALSE === $tagid and message(-1, lang('create_failed')); $read = array('tagid' => $tagid, 'name' => $name); } $tag_thread = array('tagid' => $read['tagid'], 'tid' => $tid); $threadarr[] = $tag_thread; $tagarr[$read['tagid']] = $read['name']; } } !empty($threadarr) and tag_thread_big_insert($threadarr); !empty($tagids) and well_tag_update($tagids, array('count+' => 1)); } $json = empty($tagarr) ? '' : xn_json_encode($tagarr); return $json; } ?>内容的栏目 * @param int $category 0列表 1频道 2单页 3外链 * @return array */ function category_list($forumlist, $model = 0, $display = 0, $category = 0) { if (empty($forumlist)) return NULL; static $cache = array(); $key = $model . '-' . $display . '-' . $category; if (isset($cache[$key])) return $cache[$key]; if ($display) { foreach ($forumlist as $k => $val) { if (1 == $val['display'] && 1 == $val['type'] && $val['category'] == $category) { $cache[$key][$k] = $val; } } } else { foreach ($forumlist as $k => $val) { if (1 == $val['type'] && $val['category'] == $category) { $cache[$key][$k] = $val; } } } return empty($cache[$key]) ? NULL : $cache[$key]; } /** * @param $forumlist 所有版块列表 不分模型 * @param int $display 0全部CMS栏目 1在首页和频道显示内容的栏目 * @param int $category 0列表 1频道 2单页 3外链 * @return array */ function category_list_show($forumlist, $display = 0, $category = 0) { if (empty($forumlist)) return NULL; static $cache = array(); $key = $display . '-' . $category; if (isset($cache[$key])) return $cache[$key]; if ($display) { foreach ($forumlist as $k => $val) { if (1 == $val['display'] && 1 == $val['type'] && $val['category'] == $category) { $cache[$key][$k] = $val; } } } else { foreach ($forumlist as $k => $val) { if (1 == $val['type'] && $val['category'] == $category) { $cache[$key][$k] = $val; } } } return empty($cache[$key]) ? NULL : $cache[$key]; } /** * @param $forumlist 所有版块列表 * @return mixed BBS栏目数据(仅列表) 尚未开放bbs频道功能 */ function forum_list($forumlist) { if (empty($forumlist)) return array(); static $cache = array(); if (isset($cache['bbs_forum_list'])) return $cache['bbs_forum_list']; $cache['bbs_forum_list'] = array(); foreach ($forumlist as $_fid => $_forum) { if ($_forum['type']) continue; $cache['bbs_forum_list'][$_fid] = $_forum; } return $cache['bbs_forum_list']; } // 导航显示的版块 function nav_list($forumlist) { if (empty($forumlist)) return NULL; static $cache = array(); if (isset($cache['nav_list'])) return $cache['nav_list']; foreach ($forumlist as $fid => $forum) { if (0 == $forum['nav_display']) { unset($forumlist[$fid]); } } return $cache['nav_list'] = $forumlist; } ?>电动机有什么组成
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电动机有什么组成

2025-06-09 22:35:58   0次

电动机有什么组成

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电动机主要由定子、转子、轴承、端盖、电刷装置和冷却系统等核心部件组成。定子包含铁芯和绕组，负责产生磁场；转子通过电磁感应实现机械旋转；轴承支撑转轴减少摩擦；端盖保护内部结构；电刷装置用于直流电机的电流换向；冷却系统则通过风扇或液冷方式维持工作温度。

这一结构设计的科学依据可从三方面阐述：定子与转子的电磁相互作用是电动机能量转换的基础原理。定子绕组通电后产生旋转磁场，转子导体切割磁感线产生感应电流，进而形成电磁转矩驱动机械运动。异步电动机的转子转速略低于磁场同步速，形成转差率以实现持续运转。轴承和端盖的机械支撑系统直接影响电机寿命。滚动轴承可承受每分钟数万转的高速运转，而滑动轴承更适合高负载场景。电机轴材料通常采用45号碳钢或40Cr合金钢，其抗拉强度需达到600MPa以上，并通过动平衡测试确保振动值低于2.8mm/s。第三，散热设计关乎性能稳定性。成都微精电机专利显示，轴向短壳体结合叶轮结构能使空气流量提升40%，绕组温升降幅达15℃。合肥巨一动力研究的异形转子槽设计则通过优化磁路分布，将转矩波动降低12dB，验证了结构创新对性能的提升作用。全球电动机市场规模已达9130亿元，其中亚太地区占比30%，技术进步持续推动能效标准从IE3向IE5升级，这要求各组件协同优化。例如永磁同步电机采用钕铁硼磁体使效率突破95%，而智能电机更集成编码器实现±0.1°的位置控制精度，这些演进均建立在基础结构的精密配合之上。

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电动机组成结构