Hydraulic three-indexing mechanism

Abstract

A hydraulic three-indexing mechanism relates to the technical field of indexing plates and comprises a shell, an indexing gear shaft and a driving assembly. A stepped oil cylinder hole is formed in the shell, and a left end cover and a right end cover which are provided with hydraulic oil inlets and outlets are installed at the small-hole-diameter end and the large-hole-diameter end of the stepped oil cylinder hole respectively. The side, corresponding to the stepped oil cylinder hole, of the shell is rotationally connected with an indexing gear shaft, and a driving assembly which can stop at the left position, the middle position and the right position of the stepped oil cylinder hole by controlling hydraulic oil at the two ends of the stepped oil cylinder hole to enter and exit is installed in the stepped oil cylinder hole. The driving assembly is in transmission connection with the indexing gear shaft through a gear and rack transmission mechanism and drives the indexing gear shaft to rotate in a three-indexing mode. According to the utility model, automatic three-indexing can be realized, all connecting rod necks of the six-cylinder crankshaft can be processed on one device, and repeated positioning errors are reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of indexing plates, in particular to a hydraulic three-division mechanism. Background Art

[0002] The diesel engine is mainly composed of a cylinder block, a cylinder head, a crankshaft, a camshaft, a piston, etc. The crankshaft plays a very important role in the engine; it bears the force from the connecting rod and converts it into torque, which is output through the crankshaft and drives other accessories of the engine to work; the crankshaft is subjected to the combined effects of the centrifugal force of the rotating mass, the periodically changing gas inertia force and the reciprocating inertia force, which makes the crankshaft subject to bending and torsional loads; therefore, the crankshaft needs to have sufficient strength and rigidity, and the journal surface needs to be wear-resistant, work evenly and have good balance;

[0003] The manufacturing process of the crankshaft is very demanding, and high-strength and high-precision materials and processes are required to ensure its performance and life. Generally speaking, the manufacturing process of the diesel engine crankshaft includes forging, journal milling, grinding, heat treatment and other links, among which the main journal and connecting rod neck fine grinding is one of the most critical processes. In particular, the fine grinding of the connecting rod neck usually starts with fine grinding of the main journal, and then the main journal is positioned, and the connecting rod neck is processed in sequence by eccentricity to the rotation center of the grinder using a special fixing fixture. For example, in the fine grinding of the connecting rod neck of a six-cylinder crankshaft, the 1st and 6th connecting rod necks are first processed on a grinder, and then the 2nd and 5th connecting rod necks are processed on the next grinder, and finally the 3rd and 4th connecting rod necks are processed on another grinder to complete the fine grinding of the connecting rod neck of the six-cylinder crankshaft. There are also those that use a worm gear to realize the indexing of the six-cylinder crankshaft and the follow-up grinding technology to realize the processing of the connecting rod neck on the same grinder, which mainly has the following disadvantages:

[0004] 1) Repeated positioning errors affect the accuracy of the six-cylinder crankshaft when processed sequentially. Since the phase angle of the six-cylinder crankshaft is required to be 120°±10′ and the turning radius is generally required to be ±0.05, it needs to be processed sequentially, which requires repositioning on the fine grinding fixtures of three grinders. Repeated positioning errors occur in multiple positioning, which affects the turning radius and phase angle accuracy of the connecting rod neck of the six-cylinder crankshaft.

[0005] 2) The connecting rod necks are processed sequentially, which requires three grinders and operators, increasing the investment cost and labor cost of the enterprise;

[0006] 3) Connecting rod necks are processed sequentially, which increases loading and unloading time and reduces equipment utilization;

[0007] 4) The investment in grinding equipment using follow-up grinding technology is relatively large, generally one equipment requires more than 10 million;

[0008] 5) The manual or automatic indexing of the worm gear transmission has low indexing accuracy and cannot achieve precise indexing; the above defects are problems that need to be solved urgently by technical personnel in this field.

[0009] A Chinese patent (publication number: CN101116949A) discloses a 180-degree automatic indexing device for grinding a crankshaft connecting rod neck; the patented clamp body is provided with a gear shaft through a rotary support body, a dividing plate is installed on the gear shaft, and indexing positioning blocks and adjustment pads corresponding to the dividing plate are installed on both sides of the clamp body, and an oil cylinder and its piston are provided in the clamp body, and a rack meshing with the gear shaft is provided on the piston; however, the patented piston can only move left and right under hydraulic drive to achieve 180-degree indexing, and it cannot be applied to the processing of six-cylinder crankshafts. Utility Model Content

[0010] In order to overcome the deficiencies in the background technology, the utility model discloses a hydraulic three-division mechanism.

[0011] In order to achieve the above-mentioned invention object, the utility model adopts the following technical solutions:

[0012] A hydraulic three-division mechanism comprises a housing, a division gear shaft and a driving assembly; a stepped oil cylinder hole is arranged in the housing, and the small-diameter end and the large-diameter end of the stepped oil cylinder hole are respectively provided with a left end cover and a right end cover with a hydraulic oil inlet and outlet; a division gear shaft is rotatably connected to one side of the housing corresponding to the stepped oil cylinder hole, and a driving assembly is installed in the stepped oil cylinder hole, which can stop at the left, middle and right positions of the stepped oil cylinder hole respectively by controlling the inflow and outflow of hydraulic oil at both ends of the stepped oil cylinder hole; the driving assembly is connected to the division gear shaft through a gear rack transmission mechanism, and drives the division gear shaft to rotate three degrees.

[0013] Preferably, the driving assembly includes a stepped piston shaft that can move left and right along the stepped cylinder hole, the small diameter end of the stepped piston shaft faces the large diameter end of the stepped cylinder hole, and the large diameter end end face of the stepped piston shaft is provided with a countersunk hole with a diameter larger than the diameter of the small diameter end shaft body; the small diameter end shaft body movable sleeve of the stepped piston shaft is provided with a positioning piston sleeve that slides with the large diameter end inner cavity of the stepped cylinder hole; sealing rings are provided between the positioning piston sleeve and the stepped cylinder hole, between the positioning piston sleeve and the stepped piston shaft, and between the large diameter end of the stepped piston shaft and the large diameter inner cavity of the stepped cylinder hole; the large diameter end shaft body of the stepped piston shaft is installed with a rack that meshes with the dividing gear shaft.

[0014] Preferably, an adjusting washer is provided on the shaft body between the small diameter end of the stepped piston shaft corresponding to the step surface of the stepped piston shaft and the positioning piston sleeve.

[0015] Preferably, a limit ring is installed on the small diameter end surface of the stepped piston shaft to prevent the positioning piston sleeve from separating from the stepped piston shaft.

[0016] Preferably, the large diameter end of the stepped piston shaft is provided with a recessed groove corresponding to the rack.

[0017] Preferably, the shell is provided with an oil filling hole at a position corresponding to the connection between the small-diameter end and the large-diameter end of the stepped cylinder hole.

[0018] Preferably, adjustment pads are provided between the left end cover, the right end cover and the shell.

[0019] Due to the adoption of the above-mentioned technical solution, the utility model has the following beneficial effects:

[0020] The utility model discloses a hydraulic three-division mechanism with a simple structure. It can realize automatic three-division through hydraulic oil control, ensure that all connecting rod necks of six-cylinder crankshafts can be processed on one device, and reduce repeated positioning errors. Accurate division of corresponding angles can be achieved by adjusting the thickness of corresponding gaskets, and the division accuracy is improved. The overall mechanism has a compact structure, reliable division, and low cost, which increases the processing range of ordinary connecting rod grinders and reduces enterprise investment. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of the utility model;

[0022] Figure 2 is a schematic diagram of the structure of the drive component;

[0023] Figure 3 It is a structural schematic diagram of a stepped piston shaft;

[0024] Figure 4 It is a schematic diagram of the structure of the shell.

[0025] In the figure: 1. Housing; 1-1. Stepped cylinder hole; 1-2. Oil filling hole; 2. Indexing gear shaft; 3. Driving assembly; 3-1. Stepped piston shaft; 3-2. Countersunk hole; 3-3. Sealing ring; 3-4. Rack; 3-5. Adjusting gasket; 3-6. Limiting retaining ring; 3-7. Positioning piston sleeve; 4. Left end cover; 5. Right end cover. DETAILED DESCRIPTION

[0026] The present invention can be explained in detail through the following embodiments. The purpose of disclosing the present invention is to protect all technical improvements within the scope of the present invention. In the description of the present invention, it should be understood that if there are terms such as "upper", "lower", "front", "back", "left", "right", etc. indicating directions or positional relationships, they only correspond to the drawings of the present application for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific direction.

[0027] Embodiment 1, in combination with Figures 1 to 3A hydraulic three-division mechanism comprises a housing 1, a dividing gear shaft 2 and a driving assembly 3; a stepped oil cylinder hole 1-1 is provided in the housing 1, and a left end cover 4 and a right end cover 5 with hydraulic oil inlet and outlet are respectively installed at the small-diameter end and the large-diameter end of the stepped oil cylinder hole 1-1, that is, when in use, the hydraulic oil inlet and outlet of the left end cover 4 and the right end cover 5 can be connected to the hydraulic oil circuit, and the switching valve can be used to control the on-off and switching of the hydraulic oil circuit;

[0028] The housing 1 is rotatably connected to a dividing gear shaft 2 on one side corresponding to the stepped cylinder hole 1-1, and a driving assembly 3 is installed in the stepped cylinder hole 1-1, which can stop at the left, middle and right positions of the stepped cylinder hole 1-1 respectively by controlling the inflow and outflow of hydraulic oil at both ends of the stepped cylinder hole 1-1; the driving assembly 3 is connected to the dividing gear shaft 2 through a gear rack transmission mechanism, and drives the dividing gear shaft 2 to rotate three degrees, that is, the dividing gear shaft 2 is driven to rotate by moving the driving assembly 3 left and right along the stepped cylinder hole 1-1, and the dividing gear shaft 2 is controlled to rotate by a corresponding angle by controlling the driving assembly 3 to stop at different positions;

[0029] It should be noted that the driving assembly 3 drives the indexing gear shaft 2 to rotate one circle along the stepped cylinder hole 1-1 from left to right, thereby enabling the indexing gear shaft 2 to rotate 120 degrees;

[0030] The driving assembly 3 comprises a stepped piston shaft 3-1 which can move left and right along the stepped cylinder hole 1-1, the small diameter end of the stepped piston shaft 3-1 faces the large diameter end of the stepped cylinder hole 1-1, and the large diameter end face of the stepped piston shaft 3-1 is provided with a countersunk hole 3-2 whose diameter is larger than the diameter of the shaft body at the small diameter end, and an oil chamber can be formed between the countersunk hole 3-2 and the left end cover 4;

[0031] It should be noted that the end face of the large diameter end of the stepped piston shaft 3-1 is the first indexing positioning surface, and the step surface of the stepped piston shaft 3-1 is the second and third indexing positioning surfaces;

[0032] The movable sleeve of the small-diameter end shaft body of the stepped piston shaft 3-1 is provided with a positioning piston sleeve 3-7 which is slidably matched with the inner cavity of the large-diameter end of the stepped cylinder hole 1-1; a sealing ring 3-3 is provided between the positioning piston sleeve 3-7 and the stepped cylinder hole 1-1, between the positioning piston sleeve 3-7 and the stepped piston shaft 3-1, and between the large-diameter end of the stepped piston shaft 3-1 and the large-diameter inner cavity of the stepped cylinder hole 1-1, that is, the cavity between the stepped piston shaft 3-1 corresponding to the stepped cylinder hole 1-1 and the left end cover 4 is the left oil chamber, and the cavity between the stepped piston shaft 3-1 corresponding to the stepped cylinder hole 1-1 and the right end cover 5 is the right oil chamber; the large-diameter end shaft body of the stepped piston shaft 3-1 is installed with a rack 3-4 which meshes with the indexing gear shaft 2, that is, the rack 3-4 is driven to move left and right by the stepped piston shaft 3-1 moving left and right, thereby driving the indexing gear shaft 2 to rotate;

[0033] Indexing gear shaft 2 three-degree rotation working principle:

[0034] First index 120°:

[0035] The hydraulic oil interface of the right end cover 5 is connected to the hydraulic oil, and the hydraulic oil interface of the left end cover 4 is connected to the oil return line. The stepped piston shaft 3-1 moves to the left under the action of the hydraulic oil pressure, driving the indexing gear shaft 2 to rotate, and the hydraulic oil in the oil chamber on the left side of the stepped cylinder hole 1-1 flows back to the oil tank through the hydraulic oil interface of the left end cover 4; when the first indexing positioning surface of the stepped piston shaft 3-1 contacts the left end cover 4, the stepped piston shaft 3-1 stops moving, and at this time the stepped piston shaft 3-1 is at the left position of the stepped cylinder hole 1-1;

[0036] The positioning piston sleeve 3-7 continues to move to the left under the action of the hydraulic oil pressure. When the positioning piston sleeve 3-7 contacts the step surface of the stepped cylinder hole 1-1, the positioning piston sleeve 3-7 stops moving. At this point, the indexing gear shaft 2 completes the first step of 120° indexing rotation.

[0037] Second division 120°:

[0038] The hydraulic oil interface of the left end cover 4 is connected to the hydraulic oil, and the hydraulic oil interface of the right end cover is connected to the hydraulic oil. Since the diameter of the counterbore 3-2 of the stepped piston shaft 3-1 is larger than the diameter of the shaft body at the small diameter end of the stepped piston shaft 3-1, the stepped piston shaft 3-1 moves to the right under the pressure, and drives the indexing gear shaft 2 to rotate at the same time;

[0039] When the second and third division positioning surfaces of the stepped piston shaft 3-1 contact the positioning piston sleeve 3-7, the stepped piston shaft 3-1 stops moving to the right. At this time, the stepped piston shaft 3-1 is in the middle position of the stepped cylinder hole 1-1, so that the indexing gear shaft 2 realizes the second 120° indexing rotation action.

[0040] The third division is 120°:

[0041] The hydraulic oil interface of the left end cover 4 is connected to the hydraulic oil, and the hydraulic oil interface of the right end cover 5 is connected to the oil return line. The stepped piston shaft 3-1 continues to move to the right with the positioning piston sleeve 3-7, driving the indexing gear shaft 2 to rotate;

[0042] When the second and third division positioning surfaces of the stepped piston shaft 3-1 contact the right end cover 5, the stepped piston shaft 3-1 stops moving. At this time, the stepped piston shaft 3-1 is in the right position of the stepped cylinder hole 1-1, so that the indexing gear shaft 2 realizes the second 120° indexing rotation action.

[0043] Reset:

[0044] When the hydraulic oil interface of the right end cover 5 is connected to the hydraulic oil, and the hydraulic oil interface of the left end cover 4 is connected to the oil return line, the stepped piston shaft 3-1 moves to the left, driving the indexing gear shaft 2 to rotate in the opposite direction and return to the first indexing position of 120°;

[0045] It should be noted that when in use, a six-cylinder crankshaft fixture can be installed on the end of the indexing gear shaft 2 extending out of the housing 1, the housing 1 is fastened to the six-cylinder crankshaft processing equipment, and the six-cylinder crankshaft is driven to rotate three degrees through the indexing gear shaft 2, and then the six-cylinder crankshaft is processed.

[0046] Embodiment 2, in combination with Figures 1 to 4 , a hydraulic three-division mechanism, which is different from Example 1 in that, on the basis of Example 1, an adjusting washer 3-5 is provided on the shaft body between the small-diameter end of the step piston shaft 3-1 corresponding to the step surface of the step piston shaft 3-1 and the positioning piston sleeve 3-7, and an adjusting pad is provided between the left end cover 4 and the right end cover 5 and the housing 1, and the positioning accuracy of the step piston shaft 3-1 at the left, middle and right positions in the step cylinder hole 1-1 can be adjusted by changing the thickness of the adjusting washer 3-5 and the corresponding adjusting pad, thereby improving the indexing accuracy of the indexing gear shaft 2;

[0047] The end surface of the small diameter end of the stepped piston shaft 3-1 is provided with a limit ring 3-6 to prevent the positioning piston sleeve 3-7 from being separated from the stepped piston shaft 3-1, which can prevent the positioning piston sleeve 3-7 from moving rightward when the stepped piston shaft 3-1 is located at the left position of the stepped cylinder hole 1-1, thereby causing the positioning piston sleeve 3-7 to be separated from the stepped piston shaft 3-1;

[0048] The large diameter end of the stepped piston shaft 3-1 is provided with a recessed groove corresponding to the rack 3-4 to accurately install the rack 3-4;

[0049] It should be noted that the rack 3-4 and the stepped piston shaft 3-1 can be fastened and connected correspondingly through the positioning pin holes and bolts, which effectively ensures the installation accuracy of the rack 3-4;

[0050] In addition, the shell 1 is provided with an oil filling hole 1-2 at the position where the small-diameter end and the large-diameter end of the stepped cylinder hole 1-1 are connected. Lubricating oil can enter the stepped cylinder hole 1-1 through the oil filling hole 1-2 to lubricate the bearings of the gear rack transmission mechanism and the indexing gear shaft 2, thereby improving the overall service life.

[0051] Embodiment 3, in combination with Figures 1 to 4 , a hydraulic three-division mechanism, based on embodiment 1 or 2, the hydraulic three-division mechanism of this embodiment is used for a connecting rod neck grinder to perform fine grinding on a connecting rod neck;

[0052] The finishing steps are as follows:

[0053] S1. Stop the fixture from rotating, loosen the crankshaft clamping mechanism, check the crankshaft positioning main journal and positioning pin hole, wipe them clean with a cloth, and wipe the positioning surface on the fixture to prevent impurities from affecting the crankshaft positioning accuracy;

[0054] Hoist the crankshaft into the fixture for positioning, align the positioning pin hole on the crankshaft with the positioning pin and pry the crankshaft axially so that the positioning pin on the fixture is inserted into the positioning pin hole on the crankshaft;

[0055] S2. When machining the 1st and 6th connecting rod necks of the crankshaft: give an indexing signal, the hydraulic system is controlled by the solenoid valve, the hydraulic oil interface of the right end cover 5 is connected to the pressure oil, and the hydraulic oil interface of the left end cover 4 is connected to the oil return line, the stepped piston shaft 3-1 moves to the left under the action of the pressure oil, and the hydraulic oil in the left oil chamber flows back to the oil tank through the hydraulic oil interface of the left end cover 4; when the first indexing positioning surface of the stepped piston shaft 3-1 contacts the left end cover 4, the stepped piston shaft 3-1 stops moving;

[0056] S3, the positioning piston sleeve 3-7 continues to move to the left under the action of the hydraulic oil. When the positioning piston sleeve 3-7 contacts the step surface of the housing 1, the positioning piston sleeve 3-7 stops moving, completing the first step of 120° indexing action;

[0057] S4, the crankshaft clamping mechanism clamps the workpiece and performs fine grinding of the 1st and 6th connecting rod necks of the crankshaft. After the processing is completed, the fixture stops rotating in a directional manner;

[0058] S5. When machining the 2nd and 5th connecting rod necks of the crankshaft: the crankshaft clamping mechanism is loosened, a division signal is given, the hydraulic oil interface of the left end cover 4 is connected to the pressure oil, the hydraulic oil interface of the right end cover 5 is connected to the pressure oil, and the stepped piston shaft 3-1 moves to the right under the pressure;

[0059] S6, when the second and third division positioning surfaces of the stepped piston shaft 3-1 come into contact with the positioning piston sleeve 3-7, the stepped piston shaft 3-1 stops moving rightward, and the second 120° division action is realized;

[0060] S7, the crankshaft clamping mechanism clamps the workpiece and performs fine grinding of the 2nd and 5th connecting rod necks of the crankshaft. After the processing is completed, the fixture stops rotating in a directional manner;

[0061] S8, when machining the 3rd and 4th connecting rod necks of the crankshaft: the crankshaft clamping mechanism is loosened, a division signal is given, the hydraulic oil interface of the left end cover 4 is connected to the pressure oil, the hydraulic oil interface of the right end cover 5 is connected to the return oil circuit, and the stepped piston shaft 3-1 continues to move to the right with the positioning piston sleeve 3-7;

[0062] S9, when the second and third division positioning surfaces of the stepped piston shaft 3-1 contact the right end cover 5, the stepped piston shaft 3-1 stops moving and completes the third 120° division;

[0063] S10, the crankshaft clamping mechanism clamps the workpiece and performs fine grinding of the third and fourth connecting rod necks of the crankshaft. After the machining is completed, the fixture stops rotating in a directional manner and the crankshaft clamping mechanism is released;

[0064] S11, give the indexing signal, the solenoid valve controls the hydraulic oil circuit, the hydraulic oil interface of the right end cover 5 is connected to the pressure oil, and the hydraulic oil interface of the left end cover 4 is connected to the return oil circuit, returning to the first indexing position of 120°.

[0065] S12, pull the crankshaft out of the fixture locating pin, lift the crankshaft to flow into the next process, and lift the crankshaft to be finely ground for processing.

[0066] The parts of the present invention that are not described in detail are prior art. It is obvious to those skilled in the art that the present invention is not limited to the details of the above-mentioned exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive, and it is intended that all changes that fall within the meaning and scope of equivalent elements are included in the present invention.

Claims

1. A hydraulic three-division mechanism, characterized by: The invention comprises a housing (1), a graduated gear shaft (2) and a driving assembly (3); a stepped oil cylinder hole (1-1) is provided in the housing (1); a small-diameter end and a large-diameter end of the stepped oil cylinder hole (1-1) are respectively provided with a left end cover (4) and a right end cover (5) with hydraulic oil inlet and outlet; a side of the housing (1) corresponding to the stepped oil cylinder hole (1-1) is rotatably connected to the graduated gear shaft (2); a driving assembly (3) is installed in the stepped oil cylinder hole (1-1) and can stop at three positions, namely, left, middle and right, of the stepped oil cylinder hole (1-1) by controlling the inflow and outflow of hydraulic oil at both ends of the stepped oil cylinder hole (1-1); the driving assembly (3) is transmission-connected to the graduated gear shaft (2) through a gear rack transmission mechanism, and drives the graduated gear shaft (2) to rotate three degrees.

2. The hydraulic three-division mechanism according to claim 1, characterized in that: The driving assembly (3) comprises a stepped piston shaft (3-1) that can move left and right along the stepped oil cylinder hole (1-1); the small diameter end of the stepped piston shaft (3-1) faces the large diameter end of the stepped oil cylinder hole (1-1); and the large diameter end of the stepped piston shaft (3-1) is provided with a countersunk hole (3-2) having a diameter larger than the diameter of the shaft body at the small diameter end; the shaft body movable sleeve of the small diameter end of the stepped piston shaft (3-1) is provided with a sliding sleeve that is compatible with the inner cavity of the large diameter end of the stepped oil cylinder hole (1-1); A positioning piston sleeve (3-7) is provided with a movable fit; a sealing ring (3-3) is provided between the positioning piston sleeve (3-7) and the stepped oil cylinder hole (1-1), between the positioning piston sleeve (3-7) and the stepped piston shaft (3-1), and between the large diameter end of the stepped piston shaft (3-1) and the large diameter inner cavity of the stepped oil cylinder hole (1-1); and a rack (3-4) is installed on the large diameter end of the stepped piston shaft (3-1) and meshes with the indexing gear shaft (2).

3. The hydraulic three-division mechanism according to claim 2, characterized in that: An adjusting washer (3-5) is provided on the shaft body sleeve between the small diameter end of the stepped piston shaft (3-1) and the step surface of the stepped piston shaft (3-1) and the positioning piston sleeve (3-7).

4. The hydraulic three-division mechanism according to claim 2, characterized in that: A limiting retaining ring (3-6) is installed on the small-diameter end surface of the stepped piston shaft (3-1) to prevent the positioning piston sleeve (3-7) from separating from the stepped piston shaft (3-1).

5. The hydraulic three-division mechanism according to claim 2, characterized in that: The large diameter end of the stepped piston shaft (3-1) is provided with a recessed groove corresponding to and matching the rack (3-4).

6. The hydraulic three-division mechanism according to claim 1, characterized in that: The housing (1) is provided with an oil injection hole (1-2) at a position corresponding to the connection between the small-diameter end and the large-diameter end of the stepped oil cylinder hole (1-1).

7. The hydraulic three-division mechanism according to claim 1, characterized in that: Adjustment pads are provided between the left end cover (4) and the right end cover (5) and the housing (1).

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