CN108799042A - A kind of electronic cam ring plunger pump - Google Patents

Abstract

The invention discloses an electric internal cam plunger pump, which belongs to the technical field of oil pump equipment. The plunger pump includes a left pump cover, a spindle, an inner rotor, a stator, a right pump cover, a plunger, a spring, and a transmission gear; The axes are coincident, multiple plungers on the inner rotor are in contact with the inner cam tooth surface of the stator at the same time, and the inner rotor is supported on the mandrel by a needle bearing; the left end surface of the right pump cover is in plane contact with the stator and the right end surface of the inner rotor, The right end surface of the left pump cover is in plane contact with the stator and the left end surface of the inner rotor; the left pump cover, the stator and the right pump cover are connected by bolts to form a pump body. The small gear at the shaft end of the motor meshes with the large gear on the inner rotor to drive the inner rotor to rotate, and the radial reciprocating motion of the plunger realizes oil suction and oil pressure. The plunger pump provided by the invention has the characteristics of simple structure, high mechanical efficiency, large displacement, stable operation and the like.

Description

An electric internal cam plunger pump

technical field

The invention belongs to the technical field of high-pressure oil pump equipment, and in particular relates to an electric internal cam plunger pump.

Background technique

The plunger pump belongs to the volumetric pump, which has the characteristics of compact structure, small volume, high output pressure, simple manufacture, long service life, etc. It is widely used in metallurgy, automobiles, aircrafts, mobile robots and other fields. The high-pressure radial plunger pump disclosed in Chinese patent CN 102144096B consists of a stationary cylinder, a plunger, and a rotating cam or eccentric wheel. The cam pushes the plunger to move radially and cooperates with a one-way distribution valve to work. Its disadvantage is that the uncoordinated movement of the spool and the plunger of the flow distribution valve in the high-speed state tends to cause trapped oil or vibration and noise. The connecting rod slipper type flow distribution radial plunger pump disclosed in CN102644575B adopts the connecting rod slipper type oil control valve to solve the problem of uncoordinated movement between the spool and the plunger of the flow distribution valve, but the oil control valve is relatively complicated and reliable in operation poor.

Contents of the invention

Aiming at the technical problems existing in the existing radial plunger pump, the present invention provides an electric internal cam plunger pump, which is expected to have the characteristics of compact axial structure, high output pressure, large theoretical displacement and low vibration and noise.

In order to achieve the above technical purpose, the present invention is achieved through the following technical solutions.

The invention provides an electric internal cam plunger pump, which comprises a stator (2), a left pump cover (12), a spindle (8), a right pump cover (6), an inner rotor (4), a column Plug (1), spring (3), sealing ring (5), motor (11), pinion gear (10), bull gear (14), the stator (2) is an axisymmetric cylindrical structure, and the inner cylinder There are evenly distributed internal cam teeth on the surface, the tooth width is smaller than the length of the stator (2) and distributed on both sides of the axially symmetrical surface of the stator (2), the axis of the addendum circle coincides with the axis of the outer circle of the stator (2); the left The end face of the pump cover (12) and the end face of the right pump cover (6) are all perpendicular to the axis of the stator (2), and the left and right end faces of the stator (2) are respectively connected with the left pump cover (12) and the right pump cover ( 6) keep in contact with the end faces, and the left pump cover (12), stator (2) and right pump cover (6) are connected by bolts to form a pump body; the axis of the mandrel (8) coincides with the axis of the fixed shaft, and the two The inner rotor (4) is located in the inner cam tooth chamber of the stator (2), and the inner rotor (4) is symmetrical There are radial holes evenly distributed along the circumference on the plane, axial oil distribution holes (4a) are arranged on both sides of the bottom of the radial holes, and an annular groove symmetrical to its axis is arranged on the top of the radial holes. The radial holes and the plunger ( The outer cylindrical surface of 1) slides and fits to form a moving pair. The inner rotor (4) is supported on the mandrel (8) through a needle bearing. The end surface of the pump cover (6) is kept in slidable contact, the end surface of the left pump cover (12) is provided with an axial oil inlet hole (12a) which can communicate with the oil distribution port (4a) of the inner rotor (4), and the right pump cover The end face of (6) is provided with an axial oil discharge hole (6a) which can communicate with the oil outlet of the inner rotor (4); the plunger (1) is a cylindrical axisymmetric structure, and one end of the cylinder is provided with a seal The other end of the cylinder is a spherical surface; the spring (3) is a helical compression spring, located in the cavity formed by the blind hole of the plunger (1) and the radial hole of the inner rotor (4), and the retaining column The contact between the plug (1) and the inner cam surface of the stator (2); the sealing ring (5) is installed in the sealing groove of the plunger (1), while maintaining the radial The contact of the hole; the large gear (14) is located on one side of the inner rotor (4) and is fixedly connected with the inner rotor (4), and its axis coincides with the rotation axis of the inner rotor (4); the motor (11) is located at One side of the pump body, its casing is fixedly connected with the pump body, the output shaft of the motor (11) is fixedly connected with the pinion (10), and the pinion (10) meshes with the bull gear (14) to drive the inner rotor (4) to rotate.

Further, there are m internal cam teeth evenly distributed on the circumference of the stator (2), each internal cam tooth is composed of two sections of cam profiles, that is, the oil suction profile 2a and the oil pressure profile 2b, and the tooth profile surface is a ruled surface Or curved surface; where: m≥2.

Further, the inner rotor (4) is an axisymmetric structure formed by a combination of a cylinder and m truncated cones, the axes of the truncated cones are on the same plane and perpendicular to the axis of the cylinder, and the m truncated cones coincide with the axes of the truncated cones The radial holes are evenly distributed along the circumference of the cylinder, and the m axial oil distribution holes 4a are evenly distributed along the circumference corresponding to the radial holes. Cam tooth tip circle radius; where: m≥2.

Further, the end face of the left pump cover (12) is provided with m oil inlet holes 12a, and all oil inlet holes communicate with the low-pressure chamber P0 _; the end face of the right pump cover (6) is provided with m oil inlet holes 12a. The oil discharge holes 6a, all the oil discharge holes communicate with the high-pressure chamber P1; wherein: _m≥2 .

Compared with the prior art, the present invention has the following technical effects:

1. The plungers are distributed on the circumference of the inner rotor. Multiple plungers work at the same time. When the inner rotor rotates once, each plunger absorbs and discharges oil m times, and the theoretical displacement per revolution is large.

2. The sealing ring of the plunger can automatically compensate the gap between the radial hole of the inner rotor and the wear of the plunger. At the same time, the contact gap between the end face of the inner rotor and the left and right pump covers is adjustable, which can effectively maintain the high pressure effect of the plunger pump.

3. The plunger pump has the characteristics of compact axial structure, small frictional resistance, high mechanical efficiency and stable operation.

Description of drawings

Fig. 1 is the schematic diagram of the front view structure of the electric internal cam plunger pump of the present invention;

Fig. 2 is a schematic diagram of the k-k sectional structure of Fig. 1 in the initial state of the electric internal cam plunger pump.

In the figure: 1, plunger; 2, stator; 2a, oil pressure contour; 2b, oil suction contour; 3, spring; 4, inner rotor; 4a, oil distribution hole; 5, sealing ring; 6, right pump cover; 6a , Oil drain hole; 7, Needle roller bearing; 8, Mandrel; 9, Locating pin; 10, Small gear; 11, Motor; 12, Left pump cover; 12a, Oil inlet hole; 13, Screw; 14, Big gear ;15, bolt group; P ₀ , low-pressure chamber; P ₁ , high-pressure chamber.

Detailed ways

The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments, but the present invention is not limited to the following embodiments.

In Fig. 1, a spring 3 and a plunger 1 with a seal ring 5 are installed in the radial hole of the inner rotor 4 to form a variable-volume oil cylinder, and the left side of the inner rotor 4 is fixedly connected with a large gear 14 with a screw 13 to form a plunger The rotating body of the pump. The rotating body is loaded into the inner cavity of the stator 2 from the axial direction, and the right pump cover 6 is engaged with the end face of the stator 2 and cooperates with the outer circular surface of the stator 2 for radial positioning, and the stator 2 and the right pump cover 6 are connected by a positioning pin 9 to realize Circumferential positioning. Install the mandrel 8 and the needle bearing 7 in the center hole of the inner rotor 4, the mandrel 8 is inserted into the center hole of the right pump cover 6, the motor 11 with the fixed pinion 10 at the shaft end is fixedly connected with the left pump cover 12 with screws, and then The left pump cover 12 is engaged with the end face of the stator 2 and cooperates with the positioning pin 9 for circumferential positioning. The center hole of the left pump cover 12 is matched with the shaft end of the mandrel 8. The bolts of the bolt group 15 pass through the left pump cover 12, the stator 2 and the right The pump cover 6 is connected and tightened with nuts to form a pump body.

In Fig. 2, the inner rotor 4 located in the inner cavity of the stator 2 has four radially arranged plungers 1 and corresponding oil distribution holes 4a, that is, m=4, and the stator 2 has corresponding four inner cam teeth, each The inner cam tooth is composed of an oil pressure profile 2a and an oil suction profile 2b, the axis of the mandrel 8 coincides with the rotation axis of the inner rotor 4, and a positioning pin 9 is located on the distribution circle of the bolt group 15.

When the motor 11 drives the inner rotor 4 to rotate clockwise at an angular velocity ω through the meshing of the small gear 10 and the bull gear 14, the spherical surface of the plunger 1 slides along the tooth surface of the inner cam, and with the assistance of the spring 3, the plunger is forced to move relative to the inner cam. The rotor 4 moves radially. When the plunger ₁ is in contact with the oil suction contour 2b, the oil in the low-pressure chamber P0 enters the oil cylinder through the oil inlet hole 12a and the oil distribution hole 4a, and when the plunger 1 contacts the oil pressure contour 2a, the compressed oil passes through the oil distribution hole 4a and oil drain hole 6a into the high pressure chamber P ₁ .

The rotating body composed of inner rotor 4, plunger 1 and spring 3 has no theoretical eccentricity during the rotation process, and has good dynamic balance performance. The plunger pump will not generate vibration and noise due to eccentric mass, and can adapt to high-speed rotation.

The left and right end faces of the inner rotor 4 are in planar contact with the end faces of the left pump cover 12 and the right pump cover 6, and the radial hole of the inner rotor 4 cooperates with the plunger and is sealed by the sealing ring 5 to form a closed space connected. It is beneficial to the lubrication of the small gear and the large gear, the plunger and the cam, the plunger and the inner rotor and other kinematic pairs, and can improve the service life of the plunger pump. At the same time, by adjusting the thickness of the stator to control the matching clearance of the plane contact, the high pressure effect of the rotor pump can be effectively maintained.

The radial hole of the inner rotor 4 cooperates with the plunger to form m dynamic independent closed spaces, which are both oil suction chambers and oil discharge chambers. The inner rotor rotates one revolution, the plunger absorbs oil when it touches the oil suction profile of the cam, and discharges oil when the plunger touches the oil discharge profile of the cam, and absorbs and discharges oil m times. Therefore, compared with the swash plate plunger pump, the theoretical displacement per revolution of the plunger pump is increased by m times.

Claims (4)

1. An electric internal cam plunger pump, characterized in that the plunger pump comprises a stator (2), a left pump cover (12), a mandrel (8), a right pump cover (6), an inner rotor (4) , plunger (1), spring (3), seal ring (5), motor (11), pinion gear (10), bull gear (14), described stator (2) is axisymmetric cylindrical structure, Evenly distributed inner cam teeth are arranged on the inner cylindrical surface, the tooth width is smaller than the length of the stator (2) and are distributed on both sides of the axially symmetrical plane of the stator (2), and the axis of the addendum circle coincides with the outer circle axis of the stator (2); The end face of the left pump cover (12) and the end face of the right pump cover (6) are all perpendicular to the axis of the stator (2), and the left and right end faces of the stator (2) are respectively connected with the left pump cover (12) and the right pump cover (12). The end faces of the cover (6) are kept in contact, and the left pump cover (12), the stator (2) and the right pump cover (6) are fixedly connected by bolts to form a pump body; the axis of the mandrel (8) coincides with the axis of the fixed shaft, Its two ends cooperate with the center holes of the left pump cover (12) and the right pump cover (6) respectively to form a fixed connection; the inner rotor (4) is located in the inner cam tooth chamber of the stator (2), and the inner rotor (4) There are radial holes evenly distributed along the circumference on the symmetrical plane of the radial hole, axial oil distribution holes (4a) are arranged on both sides of the bottom of the radial hole, and an annular groove symmetrical to its axis is arranged on the top of the radial hole. The outer cylindrical surface of the plug (1) slides and fits to form a moving pair. The inner rotor (4) is supported on the mandrel (8) through a needle bearing. and the end surface of the right pump cover (6) to maintain slidable contact, the end surface of the left pump cover (12) is provided with an axial oil inlet hole (12a) that can communicate with the oil distribution port (4a) of the inner rotor (4), and the right The end face of the pump cover (6) is provided with an axial oil discharge hole (6a) which can communicate with the oil outlet of the inner rotor (4); the plunger (1) is a cylindrical axisymmetric structure, and one end of the cylinder is provided with There is a sealing groove and a blind hole, and the other end of the cylinder is a spherical surface; the spring (3) is a helical compression spring, located in the cavity formed by the blind hole of the plunger (1) and the radial hole of the inner rotor (4), Keep the plunger (1) in contact with the inner cam surface of the stator (2); the seal ring (5) is installed in the seal groove of the plunger (1), while maintaining contact with the plunger (1) and the inner rotor (4) The contact of the radial hole; the large gear (14) is located on one side of the inner rotor (4) and is fixedly connected with the inner rotor (4), and its axis coincides with the rotation axis of the inner rotor (4); the motor (11 ) is located on one side of the pump body, its casing is fixedly connected with the pump body, the output shaft of the motor (11) is fixedly connected with the pinion gear (10), and the pinion gear (10) meshes with the bull gear (14) to drive the inner rotor (4) turn. 2. A kind of electric internal cam plunger pump according to claim 1, it is characterized in that m internal cam teeth are evenly distributed on the circumference of the stator (2), and each internal cam tooth consists of two sections of cam profile Composition, that is, the oil suction profile (2a) and the oil pressure profile (2b), the tooth profile surface is a ruled surface or an arc surface; wherein: m≥2. 3. A kind of electric internal lobe plunger pump according to claim 1, characterized in that, the internal rotor (4) is an axisymmetric structure formed by combining a cylinder and m frustums of cones, and the axis of the frustums of cones is located at On the same plane and perpendicular to the axis of the cylinder, m radial holes coincident with the axis of the truncated cone are evenly distributed along the circumference of the cylinder, and m axial oil distribution holes (4a) are evenly distributed along the circumference corresponding to the radial holes, so The width of the annular groove at the top of the radial hole is greater than the tooth width of the inner cam, and the radius of the annular groove is smaller than the radius of the tooth top circle of the inner cam; wherein: m≥2. 4. A kind of electric internal cam plunger pump according to claim 1, is characterized in that, the end face of described left pump cover (12) is provided with m oil inlet holes (12a), all oil inlet holes (12a ) are all communicated with the low-pressure chamber (P ₀ ); m oil discharge holes (6a) are arranged on the end face of the right pump cover (6), and all oil discharge holes (6a) are communicated with the high-pressure chamber (P ₁ ); Where: m≥2.