1. If the mixer is a 9-gear truck with high and low gear transmission

高低檔轉(zhuǎn)換時(shí)，高低檔的轉(zhuǎn)換只能在低檔的最后一個(gè)檔位4和高檔的第一個(gè)檔位5之間進(jìn)行。如果跳檔操作，比如4轉(zhuǎn)6，7轉(zhuǎn)3之類的，副箱同步器因轉(zhuǎn)速差較大，摩擦帶會(huì)早起耗損。高檔摩擦帶摩禿了，低轉(zhuǎn)高的瞬間就會(huì)聽到咔咔咔的打齒聲，反之亦然，這是因?yàn)橥狡髂Σ翈Ш簖X輪的同步工作靠同步器結(jié)合齒和低檔減速齒輪或高檔驅(qū)動(dòng)齒輪的結(jié)合齒撞擊結(jié)合所致。進(jìn)而會(huì)造成上述齒輪的打齒，在進(jìn)而會(huì)造成副箱脫檔。

During high-low gear conversion, high-low gear conversion can only be carried out between the last gear 4 of low gear and the first gear 5 of high gear. In case of gear skipping operation, such as 4 to 6, 7 to 3, the friction belt will get up early and wear out due to the large speed difference of the auxiliary box synchronizer. When the high-grade friction belt rubs bald, the clicking sound will be heard at the moment of turning low to high, and vice versa. This is because the synchronous work of the gear after the failure of the synchronizer friction belt is caused by the impact combination of the synchronizer coupling teeth and the low-grade reduction gear or the high-grade drive gear. This will cause the above gear to beat, and then cause the auxiliary box to shift out.

高低檔轉(zhuǎn)換時(shí)，由一個(gè)檔區(qū)的空檔橫拍至另一檔區(qū)的空擋后，必須有意識(shí)地稍停片刻（正常情況下1秒內(nèi)），以保證副箱同步器的轉(zhuǎn)換結(jié)合成功，一般以聽到轉(zhuǎn)換時(shí)同步器發(fā)出的啪聲為準(zhǔn)，然后再掛入你要轉(zhuǎn)換的目標(biāo)檔位即可。如果副箱還沒結(jié)合成功（野蠻換檔、氣路氣壓不穩(wěn)、氣路不暢等等因素），你就去掛主箱的檔位，就有可能造成副箱同步器斷銷等故障，嚴(yán)重的還會(huì)造成副箱爆裂。

When switching between high and low gears, you must consciously pause for a moment (within 1 second under normal circumstances) after taking a horizontal shot from the neutral of one gear zone to the neutral of another gear zone, so as to ensure the successful conversion and combination of the auxiliary box synchronizer. Generally, it is subject to the sound of the synchronizer during the conversion, and then shift into the target gear you want to convert. If the auxiliary box is not combined successfully (brutal shift, unstable air pressure in the air circuit, poor air circuit, etc.), you go to the gear of the main box, which may cause faults such as broken pin of the synchronizer of the auxiliary box, and even burst the auxiliary box.

2、如果是單H操縱的變速箱

2. In the case of a single h-operated transmission

單H操縱的變速器檔位只有一個(gè)空檔，所有的低檔和高檔對(duì)應(yīng)的檔位都是重合位置，包括空檔在內(nèi)。因此它的高低檔轉(zhuǎn)換，無(wú)法靠橫拍實(shí)現(xiàn)，而是靠駕駛室換檔手球側(cè)面的高低檔扳鈕向下向上撥動(dòng)實(shí)現(xiàn)高低檔的轉(zhuǎn)換。向下為低檔，向上為高檔。單H閥，其實(shí)就是單路的氣閥，氣流通過(guò)推動(dòng)換擋撥叉實(shí)現(xiàn)1.2.3.4檔間轉(zhuǎn)換。單H閥用于不帶副箱的基礎(chǔ)檔位切換。

The transmission gear operated by single h has only one neutral, and all gears corresponding to low gear and high gear are coincident positions, including neutral. Therefore, its high-low gear conversion can not be realized by the horizontal racket, but by the high-low gear pull button on the side of the shift handball in the cab moving downward and upward to realize the high-low gear conversion. Down is low gear and up is high gear. The single h valve is actually a single-way air valve. The air flow realizes the shift between 1.2.3.4 gears by pushing the shift fork. Single h valve is used for basic gear switching without auxiliary box.

3、如果是雙H操縱的變速箱

3. In the case of a dual h-operated transmission

雙H閥是雙路氣閥，其中一路實(shí)現(xiàn)1.2.3.4檔轉(zhuǎn)換，另外一路通過(guò)副箱實(shí)現(xiàn)高速5.6.7.8檔轉(zhuǎn)換。雙H閥主要用于帶副箱實(shí)現(xiàn)高低檔切換和基礎(chǔ)檔位切換。主箱和分動(dòng)箱是分開的，主箱的換檔動(dòng)作和副箱的換檔動(dòng)作需要同時(shí)做，結(jié)合起來(lái)才是掛高速檔，而這個(gè)需要雙路氣閥實(shí)現(xiàn)。

Double h valve is a two-way air valve, one of which realizes the shift of gear 1.2.3.4 and the other realizes the shift of high-speed gear 5.6.7.8 through the auxiliary box. Double h valve is mainly used to realize high-low gear switching and basic gear switching with auxiliary box. The main box and transfer box are separated. The shift action of the main box and the shift action of the auxiliary box need to be done at the same time. Only when combined can the high-speed gear be engaged, which needs a two-way air valve.