?排量限制器是在柱塞泵中的壓力閥和排量閥之間設(shè)置了一個凸輪（通常為柱塞桿）當柱塞桿處于垂直位置時，凸輪產(chǎn)生的扭矩驅(qū)動柱塞桿向前運動，從而將壓力輸送到活塞上導致活塞移動；而當柱塞桿處于水平位置時，凸輪產(chǎn)生的扭矩驅(qū)動柱塞桿向上運動，從而將壓力輸送到活塞上導致活塞移動。
這種凸輪結(jié)構(gòu)上不同于調(diào)節(jié)機構(gòu)或限位裝置上的凸輪桿),所以這種凸輪結(jié)構(gòu)上產(chǎn)生的扭矩沒有調(diào)節(jié)機構(gòu)大，不會給柱塞泵帶來不必要的功率損失但是這種凸輪有一個缺點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)動機中一般采用排量限制器來限制凸輪與凸輪軸的相對位置關(guān)系當需要控制某一柱塞泵單位流量時，凸輪上的凸度不能大于該固定凸度的2倍，而是應該比該固定凸度高出1-2個數(shù)量級當控制柱塞泵單位流量時，凸輪上的凸度可以大于(0°/50°)2個數(shù)量級以上。
如果該限制柱塞閥控制的柱塞壓力超過(1°/50°)1個數(shù)量級時，則凸輪上就應該設(shè)置排量限制器，以限制該調(diào)節(jié)式的應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。
