Outer circle grinding tool for hollow crankshaft

Abstract

The invention discloses a hollow crankshaft cylindrical grinding tool which comprises an adjusting connecting block, a deflector rod and a mandrel, and the two axial end faces of the mandrel are coaxially positioned and supported by a front center on a spindle driving head and a rear center of a machine tool in an abutting mode. The adjusting connecting block is radially and fixedly arranged on the outer wall of the main shaft driving head; the power output end of the adjusting connecting block is radially limited and hooked with the deflector rod relative to the front tip; the power output end of the driving lever is fixedly hooped on the mandrel, the driving lever provides rotating power for the mandrel, and the phase angle of the hollow crankshaft relative to the spindle driving head is adjusted by adjusting the connection block, the driving lever and an alignment plane radially arranged on the mandrel in a matched mode. According to the tool, crankshafts of different models can be ground by replacing the mandrel and the positioning ring, and the universality is high. And meanwhile, batch machining can be achieved through one-time alignment for workpieces produced in batches, the production efficiency is improved, and the consistency and the qualified rate of products are increased.

Description

Technical Field

[0001] The invention relates to the technical field of tooling and fixtures, in particular to a tooling for grinding the outer circle of a hollow crank shaft. Background Art

[0002] In recent years, the application field of industrial robots has been continuously developing, and the demand for high-precision, long-life, low-cost, and lightweight reducers for industrial robots has increased year by year. From the current industry perspective, the hollow reducer crankshaft external cylindrical processing tooling has poor rigidity, high product scrap rate, large grinding allowance, and low processing efficiency. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, one object of the present invention is to provide a hollow crankshaft cylindrical grinding tool, which can grind different types of crankshafts by replacing the mandrel and the positioning ring, and has strong versatility. At the same time, for batch-produced workpieces, batch processing can be achieved by aligning once, which improves production efficiency and increases product consistency and qualified rate.

[0004] In order to solve the above problems, the present invention provides a hollow crank shaft external cylindrical grinding tool, the tool includes an adjusting connecting block, a lever and a core shaft, wherein the two axial end faces of the core shaft are coaxially positioned and supported by the front center on the spindle drive head and the rear center of the machine tool; the adjusting connecting block is radially fixed on the outer wall of the spindle drive head, and the power output end of the adjusting connecting block is radially limited and hung with the lever relative to the front center; the power output end of the lever is fixedly clamped on the core shaft, and the lever provides rotational power to the core shaft, and the phase angle of the hollow crank shaft relative to the spindle drive head is adjusted by adjusting the connecting block, the lever and the radially opened alignment planes on the core shaft.

[0005] Preferably, a waist groove for connecting the main shaft drive head is opened in the middle of the adjustment connecting block, and a U-shaped groove for constraining the radial angle of the lever is opened at the power output end of the main shaft drive head; the lever is radially slidably inserted in the U-shaped groove, and a locking pin that slides and fits on the outer wall of the lever is fixedly inserted at the open end of the U-shaped groove.

[0006] Preferably, one end of the shift rod is made into a square rod, and the end and the surrounding outer walls of the square rod cooperate with the adjustment connecting block to accurately find the phase angle of the hollow crank shaft relative to the main shaft drive head; the other end of the shift rod is made into a clamping hoop, which is clamped and fixed on the power input end of the core shaft.

[0007] Preferably, the power output end of the core shaft is coaxially sleeved with: a positioning ring, a hollow crank shaft, a pressure cover and a fastening nut; the positioning ring and the pressure rod axially position and clamp the hollow crank shaft on the core shaft; the fastening nut is threadedly sleeved and connected to the core shaft.

[0008] Preferably, both the core shaft and the positioning ring are radially provided with an alignment plane, and the alignment plane cooperates with the adjustment connecting block to accurately locate the phase angle of the hollow crank shaft relative to the main shaft driving head.

[0009] Preferably, a limiting protrusion is integrally fixed to the shaft end of the positioning ring, and the limiting protrusion is clamped in the process groove of the shaft end of the hollow crank shaft to fix the positioning ring and the hollow crank shaft in circumferential rotation.

[0010] The advantages of the present invention compared with the prior art are:

[0011] The hollow crank shaft external cylindrical grinding tool of the present invention uses the mandrel as the axial support and positioning of the hollow crank shaft, and uses the front center and rear center provided by the machine tool to axially position and clamp the mandrel, and then drives the spindle drive head and the mandrel to rotate synchronously by adjusting the connecting block and the lever to accurately control the phase angle of the two, and finally the hollow crank shaft is axially clamped and positioned on the mandrel by the positioning ring, the pressure cover and the fastening nut. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or technical descriptions will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0013] Figure 1 It is a three-dimensional exploded schematic diagram of the combined structure of the present invention;

[0014] Figure 2 It is a schematic diagram of the three-dimensional structure of the adjustment connection block in the present invention;

[0015] Figure 3 is a schematic diagram of the three-dimensional structure of the lever in the present invention;

[0016] Figure 4 It is a schematic diagram of the three-dimensional structure of the core shaft in the present invention;

[0017] Figure 5 It is a schematic diagram of the three-dimensional structure of the positioning ring in the present invention;

[0018] Figure 6 It is a schematic diagram of the three-dimensional structure of the hollow crank shaft of the present invention;

[0019] In the figure: 1-spindle drive head; 2-front center; 3-adjustment connection block; 4-locking pin; 5-push rod; 6-core shaft; 7-positioning ring; 8-hollow crank shaft; 9-pressure cover; 10-fastening nut; 11-rear center; 12-waist groove; 13-U-shaped groove; 14-hoop; 15-alignment plane; 16-limiting protrusion; 17-process groove. DETAILED DESCRIPTION

[0020] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0021] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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 mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0022] The present invention is further described in detail below in conjunction with the accompanying drawings.

[0023] The present invention discloses a tool for grinding the outer cylindrical surface of a hollow crank shaft, which comprises an adjusting connection block 3, a lever 5 and a core shaft 6, wherein two axial end faces of the core shaft are coaxially positioned and supported by a front center 2 on a spindle drive head 1 and a rear center 11 of a machine tool; the adjusting connection block is radially fixed on the outer wall of the spindle drive head, and the power output end of the adjusting connection block is radially limited and hung with the lever relative to the front center; the power output end of the lever is fixedly clamped on the core shaft, and the lever provides rotational power to the core shaft, and the phase angle of the hollow crank shaft relative to the spindle drive head is adjusted by adjusting the connection block, the lever and the alignment plane 15 radially opened on the core shaft.

[0024] Preferably, a waist groove 12 for connecting the main shaft drive head is opened in the middle of the adjustment connection block, and a U-shaped groove 13 for constraining the radial angle of the lever is opened at the power output end of the main shaft drive head; the lever is radially slidably inserted in the U-shaped groove, and a locking pin 4 that slides and fits on the outer wall of the lever is fixedly inserted at the open end of the U-shaped groove.

[0025] Preferably, one end of the lever is made into a square rod, and the end and the surrounding outer walls of the square rod cooperate with the adjustment connecting block to find the phase angle of the hollow crank shaft relative to the main shaft drive head; the other end of the lever is made with a clamp 14, which is clamped and fixed on the power input end of the core shaft.

[0026] Preferably, the power output end of the core shaft is coaxially sleeved with: a positioning ring 7, a hollow crank shaft 8, a pressure cover 9 and a fastening nut 10; the positioning ring and the pressure rod axially position and clamp the hollow crank shaft on the core shaft; the fastening nut is threadedly sleeved and connected to the core shaft.

[0027] Preferably, both the core shaft and the positioning ring are radially provided with an alignment plane, and the alignment plane cooperates with the adjustment connecting block to accurately locate the phase angle of the hollow crank shaft relative to the main shaft driving head.

[0028] Preferably, a limiting protrusion 16 is integrally fixed to the shaft end of the positioning ring, and the limiting protrusion is engaged in a process groove 17 at the shaft end of the hollow crank shaft to fix the positioning ring and the hollow crank shaft in circumferential rotation.

[0029] In order to more clearly illustrate the specific implementation mode of the present invention, an embodiment is provided below:

[0030] The present invention provides a hollow crankshaft cylindrical grinding tool,

[0031] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a grinding tool for a hollow crankshaft, which can grind crankshafts of different models by replacing the mandrel and the positioning ring, and has strong versatility. At the same time, for batch-produced workpieces, batch processing can be achieved by aligning once, thereby improving production efficiency and increasing product consistency and qualified rate.

[0032] The present invention provides a grinding tool for a hollow crankshaft, which has a simple structure, low cost, low technical requirements, high efficiency and is suitable for the external cylindrical grinding of various hollow crankshafts. The tool comprises an adjustment connection block, a lever, a mandrel, a positioning ring and a pressure cover.

[0033] 1) The drive head frame is connected to the machine tool spindle head frame with screws, and the spindle rotates, driving the drive head frame to rotate together;

[0034] 2) The driving head frame and the adjustment connecting block, the adjustment connecting block and the lever are also connected to each other with screws at their corresponding positions, wherein the lever is embedded in the groove of the adjustment connecting block and rotates with the adjustment connecting block.

[0035] 3) The locating ring is fixedly connected to the mandrel, and the alignment faces of the two parts are on the same plane, which is convenient for later alignment.

[0036] 4) The gland and the fastening nut are located at the threaded end of the core shaft and serve to clamp the workpiece (hollow crank shaft).

[0037] In the present invention, the mandrel is positioned by the front and rear double centers of the grinder, has good versatility, low cost, good rigidity, high repeated positioning accuracy, and is convenient for loading and unloading workpieces.

[0038] In the present invention, the clearance between the outer circle of the core shaft and the inner hole of the workpiece is less than or equal to 0.01mm, and the positioning accuracy is high, which eliminates the step of aligning each workpiece, saves a lot of time, and improves work efficiency; in addition, due to the small clearance and high accuracy, the grinding allowance of the workpiece can also be greatly reduced, thereby reducing the processing time and greatly improving work efficiency.

[0039] In the present invention, the positioning ring is designed with an alignment plane and a limiting protrusion, and the limiting protrusion cooperates with the process groove of the workpiece, so that only the eccentricity of the first workpiece needs to be aligned, and the remaining workpieces can be directly clamped and processed, which saves a lot of alignment time. The accurate positioning improves the processing accuracy and consistency of the workpiece, and also improves the processing efficiency.

[0040] In the present invention, the lever is embedded in the groove of the adjustment connection block, and under the connection of the set screw, the lever rotates along with the adjustment connection block, and the circumferential positioning consistency is good, thereby ensuring good consistency in workpiece processing.

[0041] The present invention can be used in small or large-scale mechanical processing of various precision outer circles and eccentric circles on lathes, grinders, etc. It has the characteristics of simple processing tooling structure, low cost, strong versatility, high product consistency and high qualified rate, and has very broad application prospects in this field.

[0042] like Figure 1-6 As shown, the tooling of the present invention mainly includes an adjustment connection block, a lever, a core shaft, a positioning ring and a gland:

[0043] 1) Adjust the connection block

[0044] Figure 2 To adjust the schematic diagram of the connection block, the connection block is connected to the drive head frame with screws. When the drive head frame rotates, the connection block also rotates.

[0045] 2) Lever

[0046] Figure 3 This is a schematic diagram of the lever, which is used to drive the spindle to rotate. Its open inner hole is connected to the outer circle of the left end of the spindle, and is fixedly connected to the spindle by a threaded connection hole; its positioning surface fits with a plane of the groove of the adjustment connection block, playing a role in circumferential positioning; the main function of the lever is to determine the circumferential position relationship between the spindle headstock and the spindle, and to transmit the rotational motion of the headstock to the spindle, driving the spindle to rotate together.

[0047] 3) Mandrel

[0048] Figure 4 The schematic diagram of the mandrel is used to install the workpiece. The mandrel is installed on the front and rear centers of the machine tool by two center holes, which can obtain better clamping rigidity and workpiece processing accuracy; the front face has the same function as the positioning ring front face, and is an auxiliary surface designed for aligning the phase angle of the eccentric shaft.

[0049] 4) Locating ring

[0050] Figure 5 This is a schematic diagram of the positioning ring. Figure 6The locating ring is a device used to determine the consistency of the phase angle of the eccentric shaft. The locating ring is connected to the mandrel by screws in order to obtain circular rotation. The front face of the locating ring is an auxiliary surface designed for aligning the phase angle of the eccentric shaft. This surface is slightly higher than the front face of the mandrel to prevent interference during timing with a meter and affect the accuracy. The limiting protrusion cooperates with the process groove of the workpiece to play a circumferential positioning role, so that only the first piece needs to be aligned with the eccentricity, and the remaining workpieces can be directly clamped and processed, which can save a lot of alignment time and has accurate positioning, improving the workpiece processing accuracy and consistency, and also improving the processing efficiency.

[0051] The working principle of the present invention is:

[0052] a) Install the drive head and the front center on the grinder headstock, use the mandrel to adjust the axial distance between the rear center and the front center, the front center and the rear center are respectively firmly matched with the left and right center holes of the mandrel, so that the center penetrates 30mm on the mandrel. According to the center pressure diagram, the tip pressure is preferably 200N;

[0053] b) Install the adjustment connection block on the drive head frame through the waist groove with screws;

[0054] c) Install the lever and positioning ring on the core shaft by screws;

[0055] d) Install the workpiece (hollow crankshaft) on the mandrel and press the clamping nut onto the mandrel through the gland to prevent axial and radial movement between the workpiece and the mandrel;

[0056] e) Connecting the mandrel processing assembly with a double center through a lever and an adjustment connection block to realize the main motion of the grinding process, i.e., the rotation of the workpiece;

[0057] f) Use a lever micrometer to align the positioning ring and the front side. The error is less than or equal to 0.002. At this time, the highest point of the workpiece (hollow crankshaft) is the grinding wheel tool setting point. Operate the machine tool to set this point as the C-axis zero point, and the tool setting and installation steps before workpiece processing are completed;

[0058] If the workpiece needs to be replaced, only the mandrel needs to be removed, the fastening nut is loosened, and a new blank is replaced. The workpiece can be quickly replaced without repeating the operation process a)---f).

[0059] The present invention and its embodiments are described above, and such description is not restrictive. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. In short, if ordinary technicians in the field are inspired by it, without departing from the purpose of the invention, they can design a structure and embodiment similar to the technical solution without creativity, which should belong to the protection scope of the present invention.

Claims

1. A hollow crankshaft cylindrical grinding tool, characterized in that: The tooling includes an adjustment connection block, a lever and a core shaft, wherein the two axial end faces of the core shaft are coaxially positioned and supported by the front center on the spindle drive head and the rear center of the machine tool; the adjustment connection block is radially fixed on the outer wall of the spindle drive head, and the power output end of the adjustment connection block is radially limited and hung with the lever relative to the front center; the power output end of the lever is fixedly clamped on the core shaft, and the lever provides rotational power to the core shaft, and the phase angle of the hollow crank shaft relative to the spindle drive head is adjusted by adjusting the connection block, the lever and the radially opened alignment planes on the core shaft.

2. The hollow crankshaft cylindrical grinding tool according to claim 1, characterized in that: A waist groove for connecting the main shaft driving head is provided in the middle of the adjustment connecting block, and a U-shaped groove for constraining the radial angle of the shift rod is provided at the power output end of the main shaft driving head; the shift rod is radially slidably inserted in the U-shaped groove, and a locking pin that slides and fits on the outer wall of the shift rod is fixedly inserted at the open end of the U-shaped groove.

3. The hollow crankshaft cylindrical grinding tool according to claim 1, characterized in that: One end of the shift rod is made into a square rod, and the end and the surrounding outer walls of the square rod cooperate with the adjustment connection block to find the phase angle of the hollow crank shaft relative to the main shaft driving head; the other end of the shift rod is made into a clamping hoop, which is clamped and fixed on the power input end of the core shaft.

4. The hollow crankshaft cylindrical grinding tool according to claim 1, characterized in that: The power output end of the core shaft is provided with: a positioning ring, a hollow crank shaft, a pressure cover and a fastening nut in sequence; the positioning ring and the pressure rod are used to axially position and clamp the hollow crank shaft on the core shaft; the fastening nut is threadedly sleeved and connected to the core shaft.

5. The hollow crankshaft cylindrical grinding tool according to claim 4, characterized in that: The core shaft and the positioning ring are radially provided with an alignment plane, and the alignment plane cooperates with the adjustment connection block to accurately locate the phase angle of the hollow crank shaft relative to the main shaft driving head.

6. The tool for grinding the outer cylindrical surface of a hollow crankshaft according to claim 4, characterized in that: The shaft end of the positioning ring is integrally provided with a limiting protrusion, and the limiting protrusion is clamped in the process groove of the hollow crank shaft end to fix the positioning ring and the hollow crank shaft in circumferential rotation.

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