?排量限制器是在柱塞泵中的壓力閥和排量閥之間設(shè)置了一個(gè)凸輪（通常為柱塞桿）當(dāng)柱塞桿處于垂直位置時(shí)，凸輪產(chǎn)生的扭矩驅(qū)動(dòng)柱塞桿向前運(yùn)動(dòng)，從而將壓力輸送到活塞上導(dǎo)致活塞移動(dòng)；而當(dāng)柱塞桿處于水平位置時(shí)，凸輪產(chǎn)生的扭矩驅(qū)動(dòng)柱塞桿向上運(yùn)動(dòng)，從而將壓力輸送到活塞上導(dǎo)致活塞移動(dòng)。
這種凸輪結(jié)構(gòu)上不同于調(diào)節(jié)機(jī)構(gòu)或限位裝置上的凸輪桿),所以這種凸輪結(jié)構(gòu)上產(chǎn)生的扭矩沒(méi)有調(diào)節(jié)機(jī)構(gòu)大，不會(huì)給柱塞泵帶來(lái)不必要的功率損失但是這種凸輪有一個(gè)缺點(diǎn)就是凸輪有一定的凸度，所以在工作中很容易造成較大摩擦系數(shù)。
因此，在發(fā)動(dòng)機(jī)中一般采用排量限制器來(lái)限制凸輪與凸輪軸的相對(duì)位置關(guān)系當(dāng)需要控制某一柱塞泵單位流量時(shí)，凸輪上的凸度不能大于該固定凸度的2倍，而是應(yīng)該比該固定凸度高出1-2個(gè)數(shù)量級(jí)當(dāng)控制柱塞泵單位流量時(shí)，凸輪上的凸度可以大于(0°/50°)2個(gè)數(shù)量級(jí)以上。
如果該限制柱塞閥控制的柱塞壓力超過(guò)(1°/50°)1個(gè)數(shù)量級(jí)時(shí)，則凸輪上就應(yīng)該設(shè)置排量限制器，以限制該調(diào)節(jié)式的應(yīng)用壽命其作用是將凸輪固定在小活塞上 90-R-180-KA-5-CD-80-S-C-C8-J-03-NNN-42-42-24 90R180KA5CD80SCC8J03NNN424224 90R180-KA-5-CD-80-S-C-C8-J-03-NNN-42-42-30 90R180KA5CD80SCC8J03NNN424230 90-R-180-KA-5-CD-80-S-C-C8-J-03-NNN-42-42-30 90R180KA5CD80SCC8J03NNN424230 90-R-180-KA-5-CD-80-S-C-C8-J-05-FAC-38-38-24 90R180KA5CD80SCC8J05FAC383824 90R180-KA-5-CD-80-S-C-C8-J-06-NNN-36-36-24 90R180KA5CD80SCC8J06NNN363624 90-R-180-KA-5-CD-80-S-C-C8-J-06-NNN-36-36-24 90R180KA5CD80SCC8J06NNN363624 90R180-KA-5-CD-80-S-C-C8-J-09-FAC-35-35-28 90R180KA5CD80SCC8J09FAC353528 90-R-180-KA-5-CD-80-S-C-C8-J-09-FAC-35-35-28 90R180KA5CD80SCC8J09FAC353528 90R180-KA-5-CD-80-S-C-F1-H-03-FAC-35-35-24 90R180KA5CD80SCF1H03FAC353524 90-R-180-KA-5-CD-80-S-C-F1-H-03-FAC-35-35-24 90R180KA5CD80SCF1H03FAC353524 90R180-KA-5-CD-80-S-C-F1-J-00-NNN-42-42-24 90R180KA5CD80SCF1J00NNN424224 90-R-180-KA-5-CD-80-S-C-F1-J-00-NNN-42-42-24 90R180KA5CD80SCF1J00NNN424224 90R180-KA-5-CD-80-S-M-C8-H-03-FAC-26-26-24 90R180KA5CD80SMC8H03FAC262624 90-R-180-KA-5-CD-80-S-M-C8-H-03-FAC-26-26-24 90R180KA5CD80SMC8H03FAC262624 90R180-KA-5-CD-80-S-M-C8-H-03-FAC-42-42-24 90R180KA5CD80SMC8H03FAC424224 90-R-180-KA-5-CD-80-S-M-C8-H-03-FAC-42-42-24 90R180KA5CD80SMC8H03FAC424224 90R180-KA-5-CD-80-S-M-C8-H-04-NNN-42-42-24 90R180KA5CD80SMC8H04NNN424224 90-R-180-KA-5-CD-80-S-M-C8-H-04-NNN-42-42-24 90R180KA5CD80SMC8H04NNN424224 90R180-KA-5-CD-80-S-M-C8-J-03-NNN-42-42-24 90R180KA5CD80SMC8J03NNN424224 90-R-180-KA-5-CD-80-S-M-C8-J-03-NNN-42-42-24 90R180KA5CD80SMC8J03NNN424224 90R180-KA-5-CD-80-S-M-C8-J-05-NNN-32-32-28 90R180KA5CD80SMC8J05NNN323228 90-R-180-KA-5-CD-80-S-M-C8-J-05-NNN-32-32-28 90R180KA5CD80SMC8J05NNN323228 90R180-KA-5-CD-80-S-M-C8-J-05-NNN-35-35-28 90R180KA5CD80SMC8J05NNN353528 90-R-180-KA-5-CD-80-S-M-C8-J-05-NNN-35-35-28 90R180KA5CD80SMC8J05NNN353528 90R180-KA-5-CD-80-S-M-F1-H-03-NNN-35-35-24 90R180KA5CD80SMF1H03NNN353524 90-R-180-KA-5-CD-80-S-M-F1-H-03-NNN-35-35-24 90R180KA5CD80SMF1H03NNN353524 90R180-KA-5-CD-80-T-C-C8-J-00-NNN-17-17-24 90R180KA5CD80TCC8J00NNN171724 90-R-180-KA-5-CD-80-T-C-C8-J-00-NNN-17-17-24 90R180KA5CD80TCC8J00NNN171724 90R180-KA-5-CD-80-T-C-C8-J-03-NNN-29-29-24 90R180KA5CD80TCC8J03NNN292924。
