Iphampu yokuthambisa isebenza ngokwenza ivacuum ngepiston noma i-diaphragm. Iphampu yenziwe ngezingxenye eziningana, kuhlanganise neshubhu lokucwilisa, i-piston noma i-diaphragm, i-valve, kanye nombhobho.
Uma ucindezela iphampu, i-piston noma i-diaphragm iphonswa phansi, ukudala i-vacuum edonsa ukugcoba phezulu ngeshubhu lokucwilisa. Ivalvu ibe isivuleka, okuvumela ukugcoba kugeleze kuphume emlonyeni futhi kungene esikhumbeni.
Sekukonke, iphampu yokuthambisa iyisisetshenziswa esilula nesisebenzayo sokukhipha amafutha, futhi isetshenziswa kakhulu ezimbonini zezimonyo nezokunakekela umuntu.