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CN-117365900-B - Plunger pump

CN117365900BCN 117365900 BCN117365900 BCN 117365900BCN-117365900-B

Abstract

The invention relates to the technical field of hydraulic pumps, in particular to a plunger pump. The plunger pump comprises a motor, a pump body, a rotating shaft assembly, a piston assembly and a pressure relief assembly, wherein the rotating shaft assembly comprises a rotating shaft, a cam and a pressurizing block, the cam and the pressurizing block are sleeved on the rotating shaft, the plunger pump is provided with a pressurizing position and a pressure relief position, the motor drives the rotating shaft to rotate positively, circumferential locking between the cam and the rotating shaft is released, the pressurizing block is locked on the rotating shaft in the circumferential direction, the motor drives the rotating shaft to rotate reversely in the pressure relief position, the cam is locked on the rotating shaft in the circumferential direction, the pressurizing block and the rotating shaft release the circumferential locking, the piston assembly comprises a piston cylinder and a piston rod, one end of the piston rod extending out of the piston cylinder is in contact fit with the pressurizing block, the pressure relief assembly comprises a pressure relief cylinder, a pressure relief rod and a reset piece, and the cam drives the pressure relief rod to move axially against the elastic force of the reset piece when the rotating shaft is reversed so as to open a pressure relief opening. The invention adopts mechanical pressure relief, and each part is stable and reliable under larger pressure and is not easy to damage.

Inventors

  • XIA LI
  • ZHANG SHIQI
  • YANG YANMEI

Assignees

  • 深圳市科晶智达科技有限公司

Dates

Publication Date
20260508
Application Date
20231026

Claims (8)

  1. 1. The plunger pump is characterized by comprising a motor (2), a pump body (1), a rotating shaft assembly (3), a piston assembly (4) and a pressure release assembly (5), wherein the piston assembly (4) and the pressure release assembly (5) are arranged in the pump body (1), the rotating shaft assembly (3) comprises a rotating shaft (31), a cam (32) and a pressurizing block (33), the cam (32) and the pressurizing block (33) are sleeved on the rotating shaft (31), an output shaft of the motor (2) is connected with the rotating shaft (31) and used for driving the rotating shaft (31) to rotate positively and reversely around the self axis, the plunger pump is provided with a pressurizing position and a pressure release position, the motor (2) drives the rotating shaft (31) to rotate positively, the cam (32) and the rotating shaft (31) are released from circumferential locking, and the pressurizing block (33) are locked on the rotating shaft (31) in the circumferential direction; The piston assembly (4) comprises a piston cylinder (41) and a piston rod (42), one end of the piston rod (42) extending out of the piston cylinder (41) is in contact fit with the pressurizing block (33), and the pressurizing block (33) drives the piston rod (42) to axially reciprocate when the rotating shaft (31) rotates positively; The pressure relief assembly (5) comprises a pressure relief cylinder (51), a pressure relief rod (52) and a reset piece (54), the pressure relief rod (52) and the reset piece (54) are installed in the pressure relief cylinder (51), a pressure relief opening is formed in the pressure relief cylinder (51), the pressure relief opening is used for pressure relief of the piston cylinder (41), the pressure relief rod (52) is used for sealing the pressure relief opening in the pressurizing position, and the cam (32) drives the pressure relief rod (52) to overcome the elastic force of the reset piece (54) to axially move so as to open the pressure relief opening when the rotating shaft (31) is reversed; The cam (32) is provided with a first driving surface (322) and a second driving surface (323), the first driving surface (322) extends along the circumferential direction of the cam (32) and inclines towards the direction approaching the pressure release rod (52), the circumferential extension angle of the first driving surface (322) is smaller than 360 degrees, the second driving surface (323) is perpendicular to the moving direction of the pressure release rod (52), and one side, approaching the pressure release rod (52), of the first driving surface (322) is connected with the second driving surface (323) and used for guiding the pressure release rod (52) to be contacted with the second driving surface (323) when the cam (32) rotates; The cam (32) is provided with a notch (321) on the peripheral wall, the notch (321) penetrates through the cam (32) and is close to one axial end of the pressure relief rod (52), the end of the pressure relief rod (52) stretches into the notch (321) in the pressurizing position, the notch (321) is formed in one side wall of the reversing direction of the rotating shaft (31) to form a first driving surface (322), and the end face of the cam (32) close to the pressure relief rod (52) is formed to form a second driving surface (323).
  2. 2. The plunger pump according to claim 1, wherein the pressure relief assembly (5) further comprises a rotation member (53), the rotation member (53) being rotatably mounted on the pressure relief rod (52), the rotation axis of the rotation member (53) being perpendicular to the rotation axis of the cam (32), the peripheral wall of the rotation member (53) being in contact engagement with the first driving surface (322) and the second driving surface (323) upon rotation of the cam (32).
  3. 3. The plunger pump according to claim 1, further comprising a first stopper pin (35) and a first elastic member (36), wherein a first mounting hole extending in a radial direction is provided on an outer wall of the rotary shaft (31), one end of the first stopper pin (35) is inserted into the first mounting hole, the other end thereof abuts against an inner peripheral wall of the cam (32), and both ends of the first elastic member (36) abut against the cam (32) and the first stopper pin (35), respectively; be provided with curved first stop groove (311) on the inner peripheral wall of cam (32), the radius of first stop groove (311) is in the reverse rotation direction of pivot (31) is crescent, first stop groove (311) in one side of the forward rotation direction of pivot (31) with the smooth transition of hole wall of cam (32), opposite side with form first stop step (312) between the hole wall of cam (32), first stop step (312) are used for when pivot (31) are in reverse rotation with first stop pin (35) are along circumference stop cooperation.
  4. 4. A plunger pump according to claim 3, wherein a plurality of the first stopper grooves (311) are provided, and each of the first stopper grooves (311) is distributed in a circumferential direction of the cam (32).
  5. 5. The plunger pump according to any one of claims 1 to 4, further comprising a second stopper pin (37) and a second elastic member (38), wherein the pressurizing block (33) is provided with a second mounting hole extending in the radial direction, one end of the second stopper pin (37) is inserted into the second mounting hole, the other end thereof abuts against the outer wall of the rotating shaft (31), and both ends of the second elastic member (38) abut against the pressurizing block (33) and the second stopper pin (37), respectively; Be provided with curved second and stop groove (324) on the outer wall of pivot (31), the radius in second keeps off groove (324) is followed the direction of corotation of pivot (31) increases gradually, second keeps off groove (324) in one side of the direction of corotation of pivot (31) with the outer wall rounding off of pivot (31), form second between opposite side and the outer wall of pivot (31) and keep off step (325), second keeps off step (325) be used for when pivot (31) corotation with second keeps off round pin (37) along circumference and keeps off the cooperation.
  6. 6. The plunger pump according to any one of claims 1 to 4, wherein the pressurizing block (33) has a pressurizing surface (34), the pressurizing surface (34) having an angle with the axis of the piston rod (42) that is different from zero, the pressurizing surface (34) pushing the piston rod (42) to reciprocate in its axial direction when the pressurizing block (33) rotates.
  7. 7. The plunger pump according to claim 6, characterized in that a knuckle (43) is mounted at an end of the piston rod (42) extending out of the piston cylinder (41), the knuckle (43) being ball-hinged to the piston rod (42), a side of the knuckle (43) facing the pressure increasing surface (34) having an inclined surface adapted to the pressure increasing surface (34).
  8. 8. The plunger pump according to any one of claims 1 to 4, further comprising a rubber seal ring (7) and a plurality of metal seal rings (6), wherein the rubber seal ring (7) and the metal seal rings (6) are sleeved on one end of the piston rod (42) extending into the piston cylinder (41) so that the piston rod (42) is in sealing fit with the piston cylinder (41), and the rubber seal ring (7) is installed between the two metal seal rings (6) in the axial direction of the piston rod (42).

Description

Plunger pump Technical Field The invention belongs to the technical field of hydraulic pumps, and particularly relates to a plunger pump. Background The hydraulic pump is a power element in the hydraulic system, and the performance of the hydraulic pump directly influences the overall performance of the hydraulic system. The plunger pump is one kind of hydraulic pump, and the plunger pump makes the volume of the sealed work cavity change to realize oil sucking and pressing. In order to avoid damage to a plunger pump and a downstream system due to overlarge pressure, the existing plunger pump is provided with a hydraulic electromagnetic valve, when the pressure of the plunger pump or the downstream system is larger than a preset value, a coil of the hydraulic electromagnetic valve is electrified, and a movable iron core overcomes the elasticity of the spring and is attracted with a static iron core to drive the valve core to open a valve port, so that a pressure release channel of the hydraulic system is conducted, and a cylinder body is subjected to pressure release. Therefore, the structural characteristics of each part in the hydraulic electromagnetic valve determine the pressure relief pressure of the plunger pump, the static iron core and the movable iron core are generally made of brittle materials, the fracture toughness, the impact strength and the bending strength are weak, and the plunger pump is easy to damage under larger pressure, so that the pressure relief pressure of the plunger pump is smaller. Disclosure of Invention The invention aims to solve the technical problem that the pressure relief pressure of a plunger pump is small because an electromagnetic valve used for the existing plunger pump is easy to damage under a large pressure. In order to solve the technical problems, the embodiment of the invention provides a plunger pump which comprises a motor, a pump body, a rotating shaft assembly, a piston assembly and a pressure relief assembly, wherein the piston assembly and the pressure relief assembly are arranged in the pump body, the rotating shaft assembly comprises a rotating shaft, a cam and a pressure boost block, the cam and the pressure boost block are sleeved on the rotating shaft, an output shaft of the motor is connected with the rotating shaft and used for driving the rotating shaft to rotate forwards and reversely around the axis of the motor, the plunger pump is provided with a pressure boost position and a pressure relief position, the motor drives the rotating shaft to rotate forwards, circumferential locking between the cam and the rotating shaft is released, the pressure boost block is locked on the rotating shaft in the circumferential direction, and the motor drives the rotating shaft to rotate reversely, the cam is locked on the rotating shaft in the circumferential direction, and the pressure boost block and the rotating shaft are released from the circumferential locking; the piston assembly comprises a piston cylinder and a piston rod, one end of the piston rod extending out of the piston cylinder is in contact fit with the pressurizing block, and the pressurizing block drives the piston rod to axially reciprocate when the rotating shaft rotates positively; the pressure relief assembly comprises a pressure relief cylinder, a pressure relief rod and a reset piece, wherein the pressure relief rod and the reset piece are installed in the pressure relief cylinder, a pressure relief opening is formed in the pressure relief cylinder, the pressure relief opening is used for pressure relief of the piston cylinder, the pressure relief rod is used for blocking the pressure relief opening in the pressurizing position, and the cam drives the pressure relief rod to overcome the elastic force of the reset piece to axially move so as to open the pressure relief opening when the rotating shaft is reversed. Optionally, the cam has a first driving surface and a second driving surface, the first driving surface extends along a circumferential direction of the cam and is inclined towards a direction approaching the pressure release rod, a circumferential extension angle of the first driving surface is smaller than 360 °, the second driving surface is perpendicular to a moving direction of the pressure release rod, and one side, approaching the pressure release rod, of the first driving surface is connected with the second driving surface and is used for guiding the pressure release rod to contact with the second driving surface when the cam rotates. Optionally, a notch is formed in the peripheral wall of the cam, the notch penetrates through one axial end of the cam, close to the pressure release rod, in the pressurizing position, the end of the pressure release rod stretches into the notch, the notch is formed in the side wall of one side of the rotating shaft in the reverse rotation direction, and the end face of the cam, close to the pressure release rod, forms the second driving su