Low-stress high-speed milling diesel engine crankshaft machining device and method

Abstract

The invention provides a low-stress high-speed milling diesel engine crankshaft machining device and method. A supporting hoop body is fixed to a base, the top end of an execution screw of a hydraulic cylinder is fixedly connected with a connecting block, the connecting block is hinged to the bottom end of a compression bolt, and a rod body is in threaded connection with a locking nut; one end of the supporting hoop body is hinged to one end of the pressing hoop body, containing grooves are correspondingly formed in the other end of the pressing hoop body and the other end of the supporting hoop body, when the pressing hoop body is turned over to be combined with the supporting hoop body, the rod body of the pressing bolt can be turned over to be embedded into the containing grooves, and the locking nut can downwards abut against the other end of the pressing hoop body in a pressing mode. Therefore, the hydraulic cylinder provides clamping force for the pressing hoop body and the supporting hoop body through the pressing bolt and the locking nut. According to the milling process of the crankshaft counterweight joint surface, on the premise of ensuring the product design requirement, hydraulic automatic clamping and loosening can be achieved, the clamping time is shortened, the machining efficiency is greatly improved, the device is suitable for crankshaft parts with different journal sizes, the extra clamp manufacturing cost is reduced, and the cost is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of clamps, and in particular relates to a low-stress high-speed milling diesel engine crankshaft processing device. Background Art

[0002] The structure of the crankshaft generally consists of a main journal, a connecting rod journal, a crank, a balancing block, a front end and a rear end. The function of the crankshaft is to cooperate with the connecting rod to convert the gas pressure acting on the piston into a rotational force, transmit it to the transmission mechanism, and drive the valve mechanism, the oil supply system lubricating oil pump, the water pump and other devices at the same time. When working, the crankshaft is subjected to the effects of gas pressure, inertia force and rotational inertia, and is subjected to large and complex forces and the impact of alternating loads. In addition, since the crankshaft is a high-speed rotating part, the crankshaft requires sufficient rigidity and strength, good ability to withstand impact loads, good wear resistance and lubricity. The connecting part of the crankshaft crankshaft journal and the connecting rod journal has an elliptical interface. In order to balance the inertia force, a balancing block is cast (or fastened) on the crankshaft. The balancing block is used to balance the unbalanced centrifugal torque of the engine, and is sometimes used to balance part of the reciprocating inertia force to make the crankshaft rotate smoothly. The crankshaft balancing block targeted by the present invention is a split type, which is fastened to the crankshaft balancing weight joint surface by bolts, and the crankshaft balancing weight joint surface has dimensional accuracy and flatness requirements. In order to meet the product design requirements, the crankshaft balance weight mating surface is processed on a vertical boring and milling machine, one end of the crankshaft is clamped on the dividing head, and the crankshaft journal is supported and fixed by the support. At the same time, the journal and the support hole are ensured to rotate smoothly when the crankshaft indexes.

[0003] The traditional special fixture is used to position and clamp the crankshaft. First, when milling the crankshaft counterweight joint surface, the support fastening bolts need to be tightened to ensure that the tool chattering caused by insufficient clamping force is avoided during the cutting process. When the crankshaft rotates at indexing, the support fastening bolts need to be loosened. When the indexing is completed, the support fastening bolts need to be tightened again. Therefore, in the milling process of the crankshaft counterweight joint surface, the support fastening bolts need to be repeatedly tightened and loosened, which reduces the milling efficiency. Second, because the journal sizes of different types of crankshafts are different, and the diameter of the support hole is a fixed size, the traditional special support fixture is only suitable for the same type of crankshaft, and is not universal, resulting in high fixture costs. Summary of the invention

[0004] In view of the problems existing in the prior art, the present invention provides the following technical solutions:

[0005] A low-stress, high-speed milling diesel engine crankshaft processing device comprises a base, a supporting hoop body is fixed on the base, a hydraulic cylinder body is fixed to the base, the top end of the executing screw is fixedly connected to the bottom of the connecting block, the upper part of the connecting block is hinged to the bottom end of the clamping bolt, and a locking nut is screwed on the rod body of the clamping bolt; one end of the supporting hoop body is hinged to one end of the clamping hoop body, and the other end of the clamping hoop body and the other end of the supporting hoop body are correspondingly provided with accommodating grooves, when the clamping hoop body is flipped over to the other end thereof abutting and merging with the other end of the supporting hoop body, the rod body of the clamping bolt can be flipped over and embedded in the accommodating groove, and the locking nut on the rod body can be pressed downward against the other end of the clamping hoop body, so that the hydraulic cylinder provides clamping force for the clamping hoop body and the supporting hoop body through the clamping bolt and the locking nut.

[0006] Furthermore, a cushion block is sandwiched between the base and the supporting hoop body.

[0007] Furthermore, the clamping hoop body is detachably connected with an upper liner and an upper supporting tile via screws, and the supporting hoop body is detachably connected with a corresponding lower liner and a lower supporting tile via screws.

[0008] Furthermore, the executing screw rod passes through the base and the supporting hoop body from bottom to top respectively.

[0009] Furthermore, the upper part of the connection block is hingedly connected to a hinge sleeve to which the bottom end of the clamping bolt is fixed.

[0010] Furthermore, a travel space is formed directly below the other end of the supporting hoop body, which allows the connecting block to be lifted and lowered within a certain travel range driven by the actuating screw of the hydraulic cylinder.

[0011] The present invention also provides a method for machining a diesel engine crankshaft by low-stress and high-speed milling, which is characterized in that the above-mentioned device for machining a diesel engine crankshaft by low-stress and high-speed milling is used.

[0012] Specifically,

[0013] First, fix the base on the machine tool workbench with bolts, then fix the cushion block and the supporting hoop body on the base in turn, hinge one end of the clamping hoop body with one end of the supporting hoop body through a pin, fix the hydraulic cylinder on the base, screw the connecting block on the hydraulic cylinder's actuator screw, connect the clamping bolt with the connecting block through a pin, fasten the locking nut, and finally fix the upper gasket, lower gasket, upper supporting pad, and lower supporting pad on the clamping hoop body and the supporting hoop body with screws, connect the hydraulic pipeline of the hydraulic cylinder with the machine tool, and ensure that it can be executed through the CNC program action;

[0014] Adjust the position of the device to ensure that the deviation between the axis of the lower bearing shoe and the axis of the dividing head is within the allowable range;

[0015] When disassembling the crankshaft, first loosen the three-jaw chuck of the dividing head, loosen the locking nut, turn the clamping bolt horizontally, turn the clamping hoop body open, and lift the crankshaft out;

[0016] When clamping the crankshaft, first hoist the crankshaft to a suitable position, support the corresponding shaft neck with the supporting hoop body, flip the clamping hoop body to press it, flip the fastening bolt to vertical and insert it into the receiving groove, manually tighten the locking nut to press it against the other end of the clamping hoop body, and after alignment, lock the three-jaw chuck of the indexing head, and the CNC program controls the hydraulic cylinder to tighten the fastening bolt;

[0017] After the machining of one crankshaft counterweight joint surface is completed, the CNC program controls the hydraulic cylinder to loosen the fastening bolts. After the CNC indexing head rotates a certain angle, the CNC program controls the hydraulic cylinder to tighten the fastening bolts and continue machining the next crankshaft counterweight joint surface. The reciprocating hydraulic cylinder loosens and tightens to achieve automatic indexing rotation during the machining process.

[0018] The present invention develops a hydraulic clamping quick-change support structure for the milling process of the crankshaft counterweight joint surface. Under the premise of ensuring product design requirements, it can be hydraulically clamped and released automatically, reducing clamping time and greatly improving processing efficiency. At the same time, by replacing the support bushing, it can adapt to crankshaft parts with different journal sizes, reduce the cost of additional fixture manufacturing, and reduce scientific research and production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings that constitute a part of the present invention are used to provide further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 It is a three-dimensional schematic diagram of the present invention;

[0021] Figure 2 It is a three-dimensional schematic diagram of the present invention in an opened state;

[0022] Figure 3 This is a three-dimensional schematic diagram of the clamping state of the crankshaft according to the present invention.

[0023] The reference numerals in the figure are: base 1, hydraulic cylinder 2, cushion block 3, supporting hoop body 4, connecting block 5, pin shaft 6, fastening bolt 7, locking nut 8, clamping hoop body 9, upper gasket 10, upper supporting shoe 11, lower gasket 12, lower supporting shoe 13, screw 14. DETAILED DESCRIPTION

[0024] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0025] In the description of the embodiments of the present invention, it should be noted that the indicated orientation or position relationship is based on the orientation or position relationship shown in the accompanying drawings, or is the orientation or position relationship in which the application product is usually placed when in use, or is the orientation or position relationship commonly understood by those skilled in the art. It is only for the convenience of describing the present invention or simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed or operate in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0026] The term "plurality" in the present invention refers to more than two (including two). The terms "first", "second", etc. are only used to distinguish and describe, and should not be understood as indicating or implying relative importance.

[0027] Unless otherwise clearly specified and limited, the terms "setting", "installation" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium.

[0028] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0029] As shown in the figure, the present invention includes a base 1, on which a cushion block 3 and a supporting hoop body 4 are stacked and fixed in sequence, one end (hinge end) of a clamping hoop body 9 is hinged to one end of the supporting hoop body 4 through a pin, an upper pad 10 and an upper supporting shoe 11 are detachably connected to the clamping hoop body 9 through screws, and a corresponding lower pad 12 and a lower supporting shoe 13 are detachably connected to the supporting hoop body 4 through screws, when the clamping hoop body 9 is flipped to its other end (free end) to abut and merge with the other end of the supporting hoop body 4, the upper supporting shoe 11 and the lower supporting shoe 13 are combined to clamp the corresponding shaft neck.

[0030] The cylinder body of the hydraulic cylinder 2 is fixed on the base 1. After the actuating screw rod (i.e., telescopic rod) of the hydraulic cylinder 2 passes through the base 1, the cushion block 3, and the supporting hoop body 4 from bottom to top, the top of the actuating screw rod is screwed and fixed to the bottom of the connecting block 5. The upper part of the connecting block 5 is hinged to the hinge sleeve fixed to the bottom end of the clamping bolt 7 through the pin 6. A locking nut 8 is screwed on the rod body of the clamping bolt 7. The relative position of the locking nut 8 on the rod body of the clamping bolt 7 can be adjusted by rotation; the other end of the clamping hoop body 9 and the other end of the supporting hoop body 4 are correspondingly provided with a receiving groove for the clamping bolt 7 rod body to be flipped and embedded, and a groove for the clamping bolt 7 rod body to be turned over and embedded is formed directly below the other end of the supporting hoop body 4. The connecting block 5 is driven by the actuator screw of the hydraulic cylinder 2 to rise and fall within a certain stroke range. When the clamping hoop body 9 is flipped to its other end (free end) to abut and merge with the other end of the supporting hoop body 4, the rod body of the clamping bolt 7 can be flipped around the pin shaft 6 hinged to the connecting block 5 and embedded into the accommodating groove (41, 91), and the locking nut 8 on the rod body of the clamping bolt 7 can adjust its position on the rod body so that its lower end face is pressed downward against the end face of the other end of the clamping hoop body 9, thereby the hydraulic cylinder 2 provides a stronger and more stable clamping force for the upper supporting pad 11 of the clamping hoop body 9 and the lower supporting pad 13 of the supporting hoop body 4 through the clamping bolt 7 and the locking nut 8.

[0031] Processing method using this device:

[0032] First, fix the base 1 on the machine tool workbench (not shown in the figure) with bolts, then fix the cushion block 3 and the support hoop body 4 on the base in turn, hinge one end of the clamping hoop body 9 with one end of the support hoop body 4 through a pin, fix the hydraulic cylinder 2 on the base 1, screw the connecting block 5 on the actuator screw of the hydraulic cylinder 2, connect the clamping bolt to the connecting block through a pin, and tighten the locking nut. Finally, fix the upper gasket, lower gasket, upper support pad, and lower support pad on the clamping hoop body 9 and the support hoop body 4 with screws, and connect the hydraulic pipeline of the hydraulic cylinder to the machine tool to ensure that it can be executed through the CNC program action. Adjust the position of this device to ensure that the deviation between the axis of the lower support pad 13 and the axis of the dividing head is within the allowable range.

[0033] When disassembling the crankshaft, first loosen the three-jaw chuck of the dividing head (not shown in the figure), loosen the locking nut 8, turn the clamping bolt horizontally, turn the clamping hoop body 9 over and open, and hoist the crankshaft out; when clamping the crankshaft, first hoist the crankshaft to a suitable position, support the corresponding shaft neck with the supporting hoop body 4, turn the clamping hoop body 8 over and press it, turn the fastening bolt to vertical and embed it into the receiving groove, manually tighten the locking nut 8 to press it against the other end of the clamping hoop body 8, and after alignment, lock the three-jaw chuck of the dividing head, and the CNC program controls the hydraulic cylinder to tighten the fastening bolt.

[0034] After the machining of one crankshaft counterweight joint surface is completed, the CNC program controls the hydraulic cylinder to loosen the fastening bolts. After the CNC indexing head rotates a certain angle, the CNC program controls the hydraulic cylinder to tighten the fastening bolts and continue machining the next crankshaft counterweight joint surface. The reciprocating hydraulic cylinder loosens and tightens to achieve automatic indexing rotation during the machining process.

[0035] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A low-stress high-speed milling diesel engine crankshaft processing device, characterized in that: It includes a base, on which a supporting hoop body is fixed, a hydraulic cylinder body is fixed to the base, the top end of the executing screw is fixedly connected to the bottom of the connecting block, the upper part of the connecting block is hinged to the bottom end of the clamping bolt, and a locking nut is screwed on the rod body of the clamping bolt; one end of the supporting hoop body is hinged to one end of the clamping hoop body, and the other end of the clamping hoop body and the other end of the supporting hoop body are correspondingly provided with accommodating grooves, when the clamping hoop body is flipped to the point where its other end abuts and merges with the other end of the supporting hoop body, the rod body of the clamping bolt can be flipped and embedded in the accommodating groove, and the locking nut on the rod body can press downward against the other end of the clamping hoop body, thereby the hydraulic cylinder provides clamping force for the clamping hoop body and the supporting hoop body via the clamping bolt and the locking nut.

2. A low stress high speed milling diesel engine crankshaft processing device as claimed in claim 1, characterized in that: A cushion block is also sandwiched between the base and the supporting hoop body.

3. A low stress high speed milling diesel engine crankshaft processing device as claimed in claim 1, characterized in that: The clamping hoop body is detachably connected with an upper liner and an upper supporting tile via screws, and the supporting hoop body is detachably connected with a corresponding lower liner and a lower supporting tile via screws.

4. A low stress high speed milling diesel engine crankshaft processing device as claimed in claim 1, characterized in that: The executing screw rod passes through the base and the supporting hoop body from bottom to top respectively.

5. A low stress high speed milling diesel engine crankshaft processing device as claimed in claim 1, characterized in that: The upper part of the connecting block is hingedly connected to a hinge sleeve to which the bottom end of the clamping bolt is fixed.

6. A low stress high speed milling diesel engine crankshaft machining device as claimed in claim 1, characterized in that: A travel space is formed directly below the other end of the supporting hoop body, which can be used for the connecting block to be lifted and lowered within a certain travel range under the drive of the execution screw rod of the hydraulic cylinder.

7. A low-stress high-speed milling method for a diesel engine crankshaft, characterized in that: A low-stress, high-speed milling diesel engine crankshaft machining device as claimed in claim 1 is used.

8. A low stress high speed milling diesel engine crankshaft processing method as claimed in claim 7, characterized in that: First, fix the base on the machine tool workbench with bolts, then fix the cushion block and the support hoop body on the base in turn, hinge one end of the clamping hoop body with one end of the support hoop body through a pin, fix the hydraulic cylinder on the base, screw the connecting block on the hydraulic cylinder's actuator screw, connect the clamping bolt with the connecting block through a pin, fasten the locking nut, and finally fix the upper gasket, lower gasket, upper support pad, and lower support pad on the clamping hoop body and the support hoop body with screws, connect the hydraulic pipeline of the hydraulic cylinder with the machine tool, and ensure that it can be executed through the CNC program action; Adjust the position of the device to ensure that the deviation between the axis of the lower bearing shoe and the axis of the dividing head is within the allowable range; When disassembling the crankshaft, first loosen the three-jaw chuck of the dividing head, loosen the locking nut, turn the clamping bolt horizontally, turn the clamping hoop body open, and lift the crankshaft out; When clamping the crankshaft, first hoist the crankshaft to a suitable position, support the corresponding journal with the support hoop, flip the clamping hoop to press it, flip the fastening bolt to vertical and insert it into the receiving groove, manually tighten the locking nut to press it against the other end of the clamping hoop, and after alignment, lock the three-jaw chuck of the indexing head, and the CNC program controls the hydraulic cylinder to tighten the fastening bolt; After the machining of one crankshaft counterweight joint surface is completed, the CNC program controls the hydraulic cylinder to loosen the fastening bolts. After the CNC indexing head rotates a certain angle, the CNC program controls the hydraulic cylinder to tighten the fastening bolts and continue machining the next crankshaft counterweight joint surface. The reciprocating hydraulic cylinder loosens and tightens to achieve automatic indexing rotation during the machining process.

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