Symmetry degree assembling device for fuel injection pump and using method of symmetry degree assembling device

Abstract

The invention discloses a fuel injection pump symmetry degree assembling device and a using method thereof. The fuel injection pump symmetry degree assembling device comprises a fuel injection pump, a positioning mounting base, a guide piece, a guide rod and two pressing assemblies. The fuel injection pump comprises a pump body, a cam shaft, a flange, a plunger and barrel assembly, a plunger spring, a lower spring seat, a guide piston assembly and a pump cover assembly, the positioning mounting seat is fixedly connected with the pump body so that the axis of the cam shaft can be in the front-back direction, and the guide part is connected with a fuel outlet screw hole of the pump cover assembly; the guide rod is located above the pump cover assembly, and a guide hole which is matched with the shaft hole of the guide piece and is through in the vertical direction is formed in the guide rod; the two pressing assemblies are located on the front side and the rear side of the guiding piece correspondingly and can apply pressure to the pump cover assembly correspondingly. The fuel injection pump symmetry degree assembling device is simple in structure, easy to manufacture, low in cost and simple and convenient to use.

Description

Technical Field

[0001] The invention relates to the assembly of a fuel injection pump, and in particular to a symmetry assembly device for a fuel injection pump and a use method thereof. Background Art

[0002] Some fuel injection pumps are provided with oil outlet holes on their pump cover assemblies. The oil outlet holes have high requirements on the symmetry of the camshaft axis of the fuel injection pump. If the conventional assembly method is used, it is difficult to ensure the symmetry of the oil outlet holes. After the fuel injection pump is assembled, the oil outlet holes are sent to the metering room for detection. If the symmetry is unqualified, the parts need to be disassembled and reassembled until the symmetry of the oil outlet holes is qualified by measurement, resulting in low assembly efficiency and greatly affecting the assembly progress of the product. Summary of the invention

[0003] In view of this, an object of the present invention is to provide a fuel injection pump symmetry assembly device and a method of using the same. The fuel injection pump symmetry assembly device has a simple structure, is easy to manufacture and has low cost, and is easy to use.

[0004] A fuel injection pump symmetry assembly device in the present invention comprises a fuel injection pump, a positioning mounting seat, a guide member, a guide rod and two clamping assemblies; The fuel injection pump comprises a pump body, a camshaft, a flange, a plunger pair, a plunger spring, a lower spring seat, a guide piston assembly and a pump cover assembly, wherein the camshaft is arranged in the pump body, the flange is connected to the pump body and one end of the camshaft passes through the flange, the pump cover assembly is arranged above the pump body, and the plunger pair, the plunger spring, the lower spring seat and the guide piston assembly are all arranged in the pump body between the camshaft and the pump cover assembly; The positioning mounting seat is fixedly connected to the pump body so that the axis line of the camshaft is along the front-to-back direction, and the guide piece is connected to the oil outlet screw hole of the pump cover assembly; the guide rod is located above the pump cover assembly, and the guide rod is provided with a guide hole that penetrates along the up-down direction and cooperates with the axial hole of the guide piece; the two clamping assemblies are respectively located on the front and back sides of the guide piece, and the two clamping assemblies can respectively apply pressure to the pump cover assembly so that the pump cover assembly can overcome the elastic force of the plunger spring and move downward until it abuts against the upper end surface of the pump body.

[0005] Furthermore, the two clamping assemblies each include a stud bolt, a washer and a clamping nut, one screw portion of the stud bolt passes through the pump cover assembly and is threadedly connected to the pump body, and the other screw portion of the stud bolt is sleeved with the washer and the clamping nut.

[0006] Furthermore, the positioning mounting seat includes a base, a front positioning seat and a rear positioning seat, the lower ends of the front positioning seat and the rear positioning seat are respectively connected to the front and rear ends of the base, and the fuel injection pump is fixed between the front positioning seat and the rear positioning seat.

[0007] Furthermore, the guide rod is installed on the positioning mounting seat in a manner that it only has the freedom to slide in the up and down directions. A guide groove is respectively provided on the front positioning seat and the rear positioning seat. The opening direction of the guide groove is upward. The left and right ends of the guide rod are respectively inserted into the guide groove, and the left groove surface and the right groove surface of the guide groove are both in contact with the guide rod.

[0008] Furthermore, a connecting assembly is provided on the front positioning seat, and the connecting assembly includes a positioning pin and a plurality of first hexagon socket screws. The flange and the pump body are fixed to the front positioning seat through the connecting assembly. After the connecting assembly, the flange and the pump body are connected, the axis of the camshaft is along the front-to-back direction.

[0009] Furthermore, the specification of the oil outlet screw hole is φ32mm, and the symmetry requirement of the oil outlet screw hole of the pump cover assembly relative to the axial center line of the camshaft is not more than 0.2mm.

[0010] A method for using a fuel injection pump symmetry assembly device in the present invention adopts the fuel injection pump symmetry assembly device, comprising the following steps: S1, installing the camshaft and the flange into the lower part of the pump body, and fixing the pump body on the front positioning seat through positioning pins and a plurality of first hexagon socket screws; S2, installing the guide piston assembly, the lower spring seat, the plunger spring and the plunger pair into the pump body, and installing the pump cover assembly on the pump body, so that the pump cover assembly does not abut against the upper end surface of the pump body due to the elastic force of the plunger spring; S3, screwing the guide member into the oil outlet screw hole of the pump cover assembly, sleeve the middle part of the guide rod onto the guide member, and inserting the left and right ends of the guide rod into the guide grooves respectively; S4. Pass one end of the two stud bolts through the through holes on the pump cover assembly and screw them into the threaded holes on the pump body, screw them to the bottom and tighten them, install washers and clamping nuts on the threads of the other ends of the stud bolts, symmetrically pull the clamping nuts on the two stud bolts, so that the clamping nuts drive the washers to move downward, and the pump cover assembly overcomes the resistance of the plunger spring and moves downward, and the guide rod descends along the guide grooves of the front positioning seat and the rear positioning seat together with the pump cover assembly until the pump cover assembly is tightly attached to the upper end surface of the pump body; S5. Connect the pump cover assembly to the pump body through multiple second hexagon socket screws, remove the guide rod and the guide member, remove the fuel injection pump from the positioning mounting seat, remove the two stud bolts, washers and tightening threads, and screw the second hexagon socket screws into the threaded holes that match the stud bolts to complete the assembly of the pump cover assembly.

[0011] The beneficial effects of the present invention are as follows: the positioning mounting seat, the guide member, the guide rod and the two clamping assemblies included in the present invention have simple structures, are easy to manufacture and have low costs, and are easy to use. The pump body is fixed by the positioning mounting seat, so that the positions of the pump body, the flange and the camshaft are determined, and the axis of the camshaft is ensured to be in the front-to-back direction, and the guide rod is provided with a guide hole that matches the guide member shaft hole. After the guide hole of the guide rod is sleeved on the guide member, the clamping nuts on the two clamping assemblies are rotated at the same time, so that the guide member and the pump cover assembly overcome the resistance of the plunger spring and move downward, and the guide member moves downward along the guide groove of the positioning mounting seat. The axis of the oil outlet screw hole is coaxial with the guide hole, so as to ensure that the axis of the oil outlet screw hole always remains in the up-down direction during the movement of the pump cover assembly, that is, the axis of the camshaft and the axis of the oil outlet screw hole are perpendicular to each other, and the center line of the guide groove of the positioning mounting seat and the center line of the guide hole of the guide rod, the axis of the oil outlet screw hole of the pump cover assembly and the axis of the camshaft are on the same reference plane, so as to ensure that the symmetry requirements of the oil outlet screw hole of the pump cover assembly relative to the axis of the camshaft are met. At the same time, the two clamping assemblies are respectively on the front and rear sides of the guide member, which can balance the pressure on the front and rear sides of the pump cover assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to make the purpose, technical solution and beneficial effects of the present invention clearer, the present invention provides the following drawings for illustration: Figure 1 It is a structural schematic diagram of the present invention; Figure 2 for Figure 1 Front view of Figure 3 for Figure 2 Schematic diagram of a partial cross section of BB.

[0013] The markings in the accompanying drawings are as follows: 1-base, 2-front positioning seat, 3-rear positioning seat, 4-guide member, 5-guide rod, 6-pump body, 7-camshaft, 8-flange, 9-plunger pair, 10-plunger spring, 11-lower spring seat, 12-guide piston assembly, 13-pump cover assembly, 14-stud bolt, 15-tightening nut, 16-locating pin, 17-first hexagon socket screw, 18-guide groove, 19-washer. DETAILED DESCRIPTION

[0014] The technical solution of the present invention is described in detail below in conjunction with the accompanying drawings and embodiments.

[0015] like Figure 1-Figure 3 As shown, a fuel injection pump symmetry assembly device in this embodiment includes a fuel injection pump, a positioning mounting seat, a guide member 4, a guide rod 5 and two clamping assemblies; The fuel injection pump comprises a pump body 6, a camshaft 7, a flange 8, a plunger pair 9, a plunger spring 10, a lower spring seat 11, a guide piston assembly 12 and a pump cover assembly 13, wherein the camshaft 7 is arranged in the pump body 6, the flange 8 is connected to the pump body 6 and one end of the camshaft 7 passes through the flange 8, the pump cover assembly 13 is arranged above the pump body 6, and the plunger pair 9, the plunger spring 10, the lower spring seat 11 and the guide piston assembly 12 are all arranged in the pump body 6 between the camshaft 7 and the pump cover assembly 13; The positioning mounting seat is fixedly connected to the pump body 6 so that the axis line of the camshaft 7 is along the front-to-back direction, and the guide member 4 is connected to the oil outlet screw hole of the pump cover assembly 13; the guide rod 5 is located above the pump cover assembly 13, and the guide rod 5 is provided with a guide hole that penetrates along the up and down directions and cooperates with the axial hole of the guide member 4; the two clamping assemblies are respectively located on the front and back sides of the guide member 4, and the two clamping assemblies can respectively apply pressure to the pump cover assembly 13, so that the pump cover assembly 13 can overcome the elastic force of the plunger spring 10 and move downward until it abuts against the upper end surface of the pump body 6.

[0016] The positioning mounting seat, the guide member 4, the guide rod 5 and the two clamping assemblies have a simple structure, are easy to manufacture, have low cost and are easy to use. The pump body 6 is fixed by the positioning mounting seat, so that the positions of the pump body 6, the flange 8 and the camshaft 7 are determined, and the axis of the camshaft 7 is ensured to be in the front-to-back direction, and the guide rod 5 is provided with a guide hole that matches the axis hole of the guide member 4. After the guide hole of the guide rod 5 is sleeved on the guide member 4, the clamping nuts 15 on the two clamping assemblies are rotated at the same time, so that the guide member 4 and the pump cover assembly 13 overcome the resistance of the plunger spring 10 and move downward, and the guide member 4 moves downward along the guide groove 18 of the positioning mounting seat. The axis of the oil outlet screw hole is coaxial with the guide hole, so as to ensure that the axis of the oil outlet screw hole always remains in the up-down direction during the movement of the pump cover assembly 13, that is, the axis of the camshaft 7 and the axis of the oil outlet screw hole are perpendicular to each other, and the center line of the guide groove 18 of the positioning mounting seat and the center line of the guide hole of the guide member 4, the axis of the oil outlet screw hole of the pump cover assembly 13 and the axis of the camshaft 7 are on the same reference plane, so as to ensure that the symmetry requirement of the oil outlet screw hole of the pump cover assembly 13 relative to the axis of the camshaft 7 is met. At the same time, the two clamping assemblies are respectively on the front and rear sides of the guide member 4, so that the pressure on the front and rear sides of the pump cover assembly 13 can be relatively balanced.

[0017] In this embodiment, the two clamping assemblies each include a stud bolt 14, a washer 19 and a clamping nut 15. One of the screw parts of the stud bolt 14 passes through the pump cover assembly 13 and is threadedly connected to the pump body 6. The other screw part of the stud bolt 14 is sleeved with a washer 9 and a clamping nut 15. The washer 19 and the pump cover assembly 13 can be driven to move downward as a whole by rotating the clamping nut 15, and the guide rod 5 moves downward along the guide groove 18 of the positioning mounting seat under the action of gravity. The stud bolt 14, the washer 19 and the clamping nut 15 are all standard parts, and the manufacturing cost can be further reduced.

[0018] In this embodiment, the positioning mounting seat includes a base 1, a front positioning seat 2 and a rear positioning seat 3. The lower ends of the front positioning seat 2 and the rear positioning seat 3 are respectively connected to the front and rear ends of the base 1, and the fuel injection pump is fixed between the front positioning seat 2 and the rear positioning seat 3.

[0019] In this embodiment, the guide rod 5 is installed on the positioning mounting seat in a manner that it has only the freedom to slide in the up-down direction. A guide groove 18 is provided on each of the front positioning seat 2 and the rear positioning seat 3. The opening direction of the guide groove 18 is upward. The left and right ends of the guide rod 5 are respectively inserted into the guide groove 18. The left groove surface and the right groove surface of the guide groove 18 are both in contact with the guide rod 5. The guide rod 5 can slide in the up-down direction and can be removed from the guide groove 18, which can prevent the guide rod 5 from affecting the assembly of the pump cover assembly 13 and facilitate the disassembly after the assembly is completed.

[0020] In this embodiment, a connecting assembly is provided on the front positioning seat 2, and the connecting assembly includes a positioning pin 6 and a plurality of first hexagon socket screws 17. The flange 8 and the pump body 6 are fixed to the front positioning seat through the connecting assembly. After the connecting assembly, the flange 8 and the pump body 6 are connected, the axis of the camshaft 7 is along the front-to-back direction.

[0021] In this embodiment, the specification of the oil outlet screw hole is φ32mm, and the oil outlet screw hole of the pump cover assembly 13 is relative to the axis of the camshaft 7 ( Figure 1 The symmetry requirement for reference A) in the figure is no more than 0.2 mm.

[0022] A method for using a fuel injection pump symmetry assembly device in this embodiment, using the fuel injection pump symmetry assembly device, includes the following steps: S1, installing the camshaft 7 and the flange 8 into the lower part of the pump body 6, and fixing the pump body 6 on the front positioning seat 2 through the positioning pin 16 and a plurality of first hexagon socket screws 17; S2, install the guide piston assembly 12, the lower spring seat 11, the plunger spring 10 and the plunger pair 9 into the pump body 6, and install the pump cover assembly 13 on the pump body 6, due to the elastic force of the plunger spring 10, the pump cover assembly 13 does not abut against the upper end surface of the pump body 6; S3, screw the guide member 4 into the oil outlet screw hole of the pump cover assembly 13, cover the middle part of the guide rod 5 on the guide member 4, and insert the left and right ends of the guide rod 5 into the guide groove 18 respectively; S4. Pass one end of the two stud bolts 14 through the through holes on the pump cover assembly 13 and screw them into the threaded holes on the pump body 6, screw them to the bottom and tighten them, install washers 19 and clamping nuts 15 on the threads of the other ends of the stud bolts 14, symmetrically pull the clamping nuts 15 on the two stud bolts 14, so that the clamping nuts 15 drive the washers 19 to move downward, and the pump cover assembly 13 overcomes the resistance of the plunger spring 10 and moves downward, and the guide rod 5 descends along the guide grooves 18 of the front positioning seat 2 and the rear positioning seat 3 together with the pump cover assembly 13 until the pump cover assembly 13 is tightly attached to the upper end surface of the pump body 6; S5. Connect the pump cover assembly 13 to the pump body 6 through a plurality of second hexagon socket screws, remove the guide rod 5 and the guide member 4, remove the fuel injection pump from the positioning mounting seat, remove the two stud bolts 14, washers 19 and tightening threads 15, and screw a second hexagon socket screw into the position of the threaded hole that matches the stud bolt 14 to complete the assembly of the pump cover assembly 13.

[0023] The above steps of the method for using the fuel injection pump symmetry assembly device are simple to operate and easy to implement.

[0024] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A fuel injection pump symmetry assembly device, characterized in that: It comprises a fuel injection pump, a positioning mounting seat, a guide member (4), a guide rod (5) and two clamping assemblies; The fuel injection pump comprises a pump body (6), a camshaft (7), a flange (8), a plunger pair (9), a plunger spring (10), a lower spring seat (11), a guide piston assembly (12) and a pump cover assembly (13); the camshaft (7) is arranged in the pump body (6); the flange (8) is connected to the pump body (6) and one end of the camshaft (7) passes through the flange (8); the pump cover assembly (13) is arranged above the pump body (6); the plunger pair (9), the plunger spring (10), the lower spring seat (11) and the guide piston assembly (12) are all arranged in the pump body (6) between the camshaft (7) and the pump cover assembly (13); The positioning mounting seat is fixedly connected to the pump body (6) so that the axis of the camshaft (7) is along the front-to-back direction, and the guide member (4) is connected to the oil outlet screw hole of the pump cover assembly (13); the guide rod (5) is located above the pump cover assembly (13), and the guide rod (5) is provided with a guide hole that penetrates along the up-down direction and cooperates with the axis hole of the guide member (4); the two clamping assemblies are respectively located on the front and back sides of the guide member (4), and the two clamping assemblies can respectively apply pressure to the pump cover assembly (13) so that the pump cover assembly (13) can overcome the elastic force of the plunger spring (10) and move downward until it abuts against the upper end surface of the pump body (6).

2. The fuel injection pump symmetry assembly device according to claim 1, characterized in that: The two clamping assemblies each comprise a stud bolt (14), a washer (19) and a clamping nut (15); one screw portion of the stud bolt (14) passes through the pump cover assembly (13) and is threadedly connected to the pump body (6); the other screw portion of the stud bolt (14) is sleeved with the washer (19) and the clamping nut (15).

3. The fuel injection pump symmetry assembly device according to claim 2, characterized in that: The positioning mounting seat comprises a base (1), a front positioning seat (2) and a rear positioning seat (3); the lower ends of the front positioning seat (2) and the rear positioning seat (3) are respectively connected to the front and rear ends of the base (1); and the fuel injection pump is fixed between the front positioning seat (2) and the rear positioning seat (3).

4. The fuel injection pump symmetry assembly device according to claim 3, characterized in that: The guide rod (5) is mounted on the positioning mounting seat in a manner that it has only the freedom to slide in the up-down direction. A guide groove (18) is provided on each of the front positioning seat (2) and the rear positioning seat (3). The opening direction of the guide groove (18) is upward. The left and right ends of the guide rod (5) are respectively inserted into the guide groove (18). The left groove surface and the right groove surface of the guide groove (18) are both in contact with the guide rod (5).

5. The fuel injection pump symmetry assembly device according to claim 3 or 4, characterized in that: A connecting assembly is provided on the front positioning seat (2), the connecting assembly comprising a positioning pin (6) and a plurality of first hexagon socket screws (17); the flange (8) and the pump body (6) are fixed to the front positioning seat via the connecting assembly; after the connecting assembly, the flange (8) and the pump body (6) are connected, the axis of the camshaft (7) is along the front-rear direction.

6. The fuel injection pump symmetry assembly device according to claim 5, characterized in that: The specification of the oil outlet screw hole is φ32 mm, and the symmetry of the oil outlet screw hole of the pump cover assembly (13) relative to the axis of the camshaft (7) is required to be no more than 0.2 mm.

7. A method for using a fuel injection pump symmetry assembly device, characterized in that: The symmetry assembly device for the fuel injection pump as claimed in claim 5 or 6 comprises the following steps: S1, installing the camshaft (7) and the flange (8) into the lower part of the pump body (6), and fixing the pump body (6) on the front positioning seat (2) via a positioning pin (16) and a plurality of first hexagon socket head screws (17); S2, installing the guide piston assembly (12), the lower spring seat (11), the plunger spring (10) and the plunger pair (9) into the pump body (6), and installing the pump cover assembly (13) on the pump body (6), so that the pump cover assembly (13) does not abut against the upper end surface of the pump body (6) due to the elastic force of the plunger spring (10); S3, screwing the guide member (4) into the oil outlet screw hole of the pump cover assembly (13), fitting the middle portion of the guide rod (5) onto the guide member (4), and inserting the left and right ends of the guide rod (5) into the guide grooves (18) respectively; S4. Pass one end of the two stud bolts (14) through the through holes on the pump cover assembly (13) and screw them into the threaded holes on the pump body (6), screw them to the bottom and tighten them, install washers (19) and clamping nuts (15) on the threads of the other ends of the stud bolts (14), symmetrically turn the clamping nuts (15) on the two stud bolts (14) so ​​that the clamping nuts (15) drive the washers (19) to move downward, and the pump cover assembly (13) overcomes the resistance of the plunger spring (10) and moves downward, and the guide rod (5) descends along the guide grooves (18) of the front positioning seat (2) and the rear positioning seat (3) together with the pump cover assembly (13) until the pump cover assembly (13) is tightly attached to the upper end surface of the pump body (6); S5. Connect the pump cover assembly (13) to the pump body (6) through a plurality of second hexagon socket screws, remove the guide rod (5) and the guide member (4), remove the fuel injection pump from the positioning mounting seat, remove the two stud bolts (14), washers (19) and the clamping thread (15), and screw a second hexagon socket screw into each threaded hole that matches the stud bolt (14) to complete the assembly of the pump cover assembly (13).

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