Center frame for grinding machine

Abstract

The utility model provides a center frame for a grinding machine. The center frame comprises a base, a hydraulic cylinder, two pre-tightening force fine adjustment mechanisms, a fine adjustment mechanism installation seat and a workpiece supporting mechanism. A piston rod of the hydraulic cylinder is connected with the fine adjustment mechanism mounting seat; the two pre-tightening force fine adjustment mechanisms are arranged in parallel up and down, the adjusting rod is fixedly connected to the fine adjustment mechanism mounting seat, the compression spring is accommodated in the adjusting rod, the adjusting screw axially extrudes one end of the compression spring, and the ejector rod is in contact with the compression spring; the side supporting assembly comprises an anti-rotating rod and a first contact for supporting the side of a workpiece, the first contact is connected to an ejector rod, the bottom supporting assembly comprises an ejector rod piece, a rotating shaft, a tension spring and a second contact which supports the bottom of the workpiece and is connected to the ejector rod piece, and the ejector rod piece can rotate around the rotating shaft under the action of the ejector rod. And the tension spring keeps the ejector rod sheet in place when the ejector rod sheet does not rotate. Synchronous movement in two directions can be guaranteed without high-precision matching parts, the requirement for design precision is low, pretightening force can be manually and finely adjusted, and applicability is high.

Description

Technical Field

[0001] The utility model belongs to the field of grinding machine tools, and in particular relates to a center frame used for a grinding machine. Background Art

[0002] When grinding crankshafts or eccentric shafts, grinders generally use double-top grinding. Compared with ordinary shaft parts, crankshaft grinding has the following problems: 1. Due to the large eccentricity of the crankshaft or eccentric shaft itself, when the workpiece rotates with the headstock, the workpiece axis will swing under the action of centripetal force; 2. Due to the special structure of the crankshaft, the crankshaft will bend and deform due to the grinding force and the clamping force during double-top grinding.

[0003] Due to the characteristics of crankshaft processing itself, a set of center frames is needed to help center the workpiece and help unload the head and tail frames. At the same time, the tightening force of the center frame can be adjusted according to different grinding processes.

[0004] The existing grinding machine center frame, such as the hydraulic center frame for grinding machines proposed in the Chinese patent application with announcement number CN217143569U, includes a fine-tuning feed cylinder, a chute plate, a tension spring, two wedges, two support arms and two support blocks. Although the center frame can meet the use requirements, it needs to design the chute plate with high precision to ensure synchronous feeding in the horizontal and vertical directions, and it is also necessary to ensure that the inclination angles of the two wedges are the same to achieve simultaneous and equal displacement movement of the two support arms and the two support blocks. The design accuracy requirements are high. In addition, when the center frame is in use, the wear between the high-precision components and the related components is easy to affect the centering accuracy of the center frame. When wear occurs, manual adjustment is not allowed to fine-tune the preload force, so the applicability is poor. Utility Model Content

[0005] The utility model aims to solve the shortcomings of the prior art that the center frame of a grinding machine has high design precision requirements and poor applicability, and provides a center frame for a grinding machine, which has low design precision requirements, can also manually fine-tune the preload force, and has strong applicability.

[0006] To achieve the above purpose, the technical solution provided by the utility model is:

[0007] A center frame for a grinding machine, which is special in that it comprises a base, a hydraulic cylinder, two preload fine-tuning mechanisms, a fine-tuning mechanism mounting seat and a workpiece supporting mechanism;

[0008] The base is used to support the hydraulic cylinder, the preload fine-tuning mechanism and the workpiece support mechanism;

[0009] The hydraulic cylinder is mounted on the base to provide driving force for the workpiece support mechanism, and the piston rod of the hydraulic cylinder is connected to the fine-tuning mechanism mounting seat;

[0010] The two preload fine-tuning mechanisms are arranged in parallel up and down, and each comprises an adjusting rod, a compression spring, an adjusting screw, a locking nut and a push rod. The adjusting rod is arranged horizontally and fixedly connected to the fine-tuning mechanism mounting seat. The compression spring is horizontally accommodated in the adjusting rod. The adjusting screw is axially pressed on one end of the compression spring and locked by the locking nut. One end of the push rod contacts the other end of the compression spring.

[0011] The workpiece support mechanism includes a side support assembly and a bottom support assembly.

[0012] The side support assembly includes an anti-rotation rod and a first contact for supporting the side of the workpiece, the first contact is connected to the other end of the top rod of one of the two preload fine-tuning mechanisms located at the top, the anti-rotation rod is connected to the adjustment rod and the first contact and can move left and right relative to the adjustment rod.

[0013] The bottom support assembly includes a push rod piece, a rotating shaft, a tension spring and a second contact for supporting the bottom of the workpiece and connected to the push rod piece. The push rod piece contacts the other end of the push rod of one of the two preload fine-tuning mechanisms located at the bottom. The rotating shaft is fixed to the base. The push rod piece is installed on the rotating shaft and can rotate around the rotating shaft under the action of the push rod. One end of the tension spring is fixed to the base, and the other end is fixed to the push rod piece to keep the push rod piece in place when the push rod piece is not rotated.

[0014] Furthermore, the center frame for the grinding machine also includes a guide mechanism, which is used to guide the workpiece support mechanism and includes a linear bearing mounted to the base and a guide rod passing therethrough, and the guide rod is fixedly connected to the fine-tuning mechanism mounting seat.

[0015] Furthermore, the guide mechanism also includes a bearing mounting seat, the bearing mounting seat is connected to the base, and the linear bearing is accommodated in the bearing mounting seat.

[0016] Furthermore, one guide mechanism is arranged at each of the upper and lower ends of the fine-tuning mechanism mounting seat.

[0017] Furthermore, the bottom support assembly also includes a fixing plate and a fixing plate tightening screw, the fixing plate is fixedly connected to the base, and the rotating shaft passes through the fixing plate and is fixed by the fixing plate tightening screw.

[0018] Furthermore, the bottom support assembly also includes a rolling bearing, the inner ring of the rolling bearing is sleeved on the rotating shaft, and the outer ring is installed in the top rod piece.

[0019] Furthermore, the center frame for the grinding machine also includes a detection unit, which includes a sensor and a sensor bracket. The sensor bracket is installed on the base, and the sensor is connected to the sensor bracket for determining the position of the push rod through position detection.

[0020] Furthermore, the detection unit also includes a sensing bracket, which is connected to the fine-tuning mechanism mounting base to determine the position of the ejector rod by detecting the position of the sensing bracket.

[0021] The advantages of the utility model are:

[0022] 1. The center frame of the grinding machine of the utility model uses a hydraulic cylinder to drive a fine-tuning mechanism mounting seat and two preload fine-tuning mechanisms arranged in parallel up and down. The two preload fine-tuning mechanisms each include a horizontally arranged adjustment rod, a compression spring, an adjusting screw, a locking nut and a push rod. The push rod of one preload fine-tuning mechanism is connected to a first contact supporting the side of a workpiece, and the push rod of the other preload fine-tuning mechanism acts on a push rod piece that can surround a rotating shaft. The push rod piece drives the connected second contact to support the bottom of the workpiece, and the push rod piece is held in place by a tension spring when it is rotated into place. Therefore, through the utility model, the preload force of the workpiece can be adjusted in combination with the hydraulic cylinder and the preload force fine-tuning mechanism, wherein, when the hydraulic cylinder is used to adjust the preload force, the two preload force fine-tuning mechanisms are driven simultaneously along with the fine-tuning mechanism mounting seat to make the two push rods move horizontally at the same time, one push rod directly drives the first contact to move, and the other push rod pushes the push rod piece to rotate after being translated a certain distance, thereby driving the second contact to rotate, and the two contacts support the workpiece at the same time. Therefore, the utility model does not require high-precision matching components to ensure synchronous movement in two directions, and the design accuracy requirement is low; when the preload force fine-tuning mechanism is used to manually fine-tune the preload force, the adjusting screw therein can be screwed to move the push rod left and right through the compression spring, and then the adjusting screw can be locked with a locking nut. Therefore, in addition to realizing preload force adjustment through the hydraulic cylinder, the utility model can also manually fine-tune the preload force through the preload force fine-tuning mechanism, and has strong applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The features and advantages of the present invention will become more easily understood through the following description with reference to the accompanying drawings, which are not drawn to scale and some features are enlarged or reduced to show details of specific components. In the accompanying drawings:

[0024] Figure 1 This is a front view of the center frame used for the grinding machine of the utility model when the workpiece is not pressed against it;

[0025] Figure 2 yes Figure 1 A side view of a center rest for a grinding machine;

[0026] Figure 3 This is a front view of the center frame used for the grinding machine of the utility model when it is pressed against the workpiece;

[0027] Figure 4 It is a cross-sectional view of a preload fine-adjusting mechanism and a side support assembly in a center frame of a grinding machine according to the utility model;

[0028] Figure 5 It is a cross-sectional view of a bottom support assembly of the center frame of a grinding machine according to the present invention.

[0029] In the figure:

[0030] 1-base, 11-oil inlet, 12-oil outlet, 13-base fixing screw;

[0031] 2-Hydraulic cylinder;

[0032] 3- preload fine-tuning mechanism, 31- adjusting rod, 32- compression spring, 33- adjusting screw, 34- locking nut, 35- ejector rod, 36- adjusting rod jacking screw;

[0033] 4- Fine-tuning mechanism mounting seat;

[0034] 5-side support assembly, 51-anti-rotation rod, 52-first contact;

[0035] 6- bottom support assembly, 61- push rod, 62- rotating shaft, 63- tension spring, 64- second contact, 65- draw hook, 66- fixing plate, 67- rotating shaft tightening screw, 68- rolling bearing, 69- inner ring screw, 681- inner ring tightening gasket, 682- outer ring tightening screw;

[0036] 71- linear bearing, 72- guide rod, 73- bearing mounting seat, 74- bearing clamping screw, 75- sensor, 76- sensor bracket, 77- induction bracket;

[0037] 100-artifacts. DETAILED DESCRIPTION

[0038] The present invention will be described in detail below with reference to the accompanying drawings by means of exemplary embodiments of the present invention. It should be noted that the following detailed description of the present invention is only for the purpose of illustration, and is not intended to limit the present invention.

[0039] The utility model provides a center frame for a grinding machine, which is used for being fixed on a working table of the grinding machine and provides an adjustable pre-tightening force to a crankshaft or an eccentric shaft workpiece to be ground so as to assist the grinding of the workpiece.

[0040] Reference Figures 1 to 3As an exemplary embodiment of the utility model, a center frame for a grinding machine includes a base 1, a hydraulic cylinder 2, two preload fine-tuning mechanisms 3, a fine-tuning mechanism mounting seat 4 and a workpiece support mechanism. The base 1 is used to support the hydraulic cylinder 2, the preload fine-tuning mechanism 3 and the workpiece support mechanism. The hydraulic cylinder 2 is used to provide a driving force for the workpiece support mechanism and synchronously adjust the workpiece preload through the hydraulic system. The preload fine-tuning mechanism 3 is used to manually fine-tune the workpiece preload. The fine-tuning mechanism mounting seat 4 is used to install the preload fine-tuning mechanism 3. The workpiece support mechanism is used to support the side and bottom of the workpiece 100.

[0041] The base 1 can be connected to the grinding machine table by base fixing screws 13 .

[0042] The cylinder barrel of the hydraulic cylinder 2 is mounted to the base 1, and is particularly fixed to the base 1 by screw connection, and the piston rod of the hydraulic cylinder 2 is connected to the fine adjustment mechanism mounting seat 4. The oil inlet 11 and the oil outlet 12 of the hydraulic circuit can be arranged on the same side of the base 1, that is, an interface communicating with the oil port of the hydraulic cylinder 2 is arranged on the same side of the base 1.

[0043] Combination Figure 4 The two preload fine-tuning mechanisms 3 are arranged in parallel up and down, and each includes an adjustment rod 31, a compression spring 32, an adjustment screw 33, a locking nut 34 and a push rod 35 whose axis is arranged in the horizontal direction. The adjustment rod 31 is arranged horizontally and fixed to the fine-tuning mechanism mounting seat 4, and can be optionally fixed to the fine-tuning mechanism mounting seat 4 by two adjustment rod locking screws 36. The preload fine-tuning mechanism 3 is particularly arranged in front of the hydraulic cylinder 2 to facilitate the fixing and adjustment operation of the preload fine-tuning mechanism 3. The compression spring 32 is horizontally accommodated in the adjustment rod 31, the adjustment screw 33 is axially pressed on one end of the compression spring 32 and locked by the locking nut 34, one end of the push rod 35 is in contact with the other end of the compression spring 32, and the push rod 35 can also be designed to pass through the middle of the compression spring 32 to guide the compression spring 32. When the preload fine-tuning mechanism 3 is needed to fine-tune the preload of the workpiece, first loosen the locking nut 34 and then rotate the adjusting screw 33 to release or squeeze the compression spring 32 to move the push rod 35 left and right, and then lock the adjusting screw 33 with the locking nut 34.

[0044] The workpiece support mechanism includes a side support assembly 5 and a bottom support assembly 6, which support the side and bottom of the workpiece 100 respectively.

[0045] Combined with reference Figure 4The side support assembly 5 includes an anti-rotation rod 51 and a first contact 52 for supporting the side of the workpiece 100. The first contact 52 is connected to the other end of the top rod 35 of one of the two preload fine-tuning mechanisms 3 located at the top, and can be connected by screws as shown in the figure. The anti-rotation rod 51 is used to prevent the first contact 52 from rotating. The anti-rotation rod 51 connects the adjustment rod 31 and the first contact 52 and can move left and right relative to the adjustment rod 31 to allow the first contact 52 to move with the top rod 35 and not rotate when the top rod 35 moves.

[0046] like Figure 5 As shown, the bottom support assembly 6 includes a push rod piece 61, a rotating shaft 62, a tension spring 63, and a second contact 64 for supporting the bottom of the workpiece 100 and connected to the push rod piece 61. The second contact 64 can be screwed to the push rod piece 61. The push rod piece 61 contacts the other end of the push rod 35 of one of the two preload fine-tuning mechanisms 3 located at the bottom so as to be pushed by the push rod 35. The rotating shaft 62 is fixed to the base 1. The push rod piece 61 is installed on the rotating shaft 62 and can rotate around the rotating shaft 62 under the action of the push rod 35. The shape of the push rod piece 61 is not limited, but it is designed to be rotated under the push of the push rod 35 to drive the second contact 64 to support the workpiece 100 together with the first contact 52. One end of the tension spring 63 is fixed to the base 1, and the other end is fixed to the push rod piece 61 to keep the push rod piece 61 in place when the push rod piece 61 is not rotated, thereby preventing the second contact 64 from contacting the workpiece 100. In particular, both ends of the tension spring 63 may be fixed by the hooks 65 , respectively.

[0047] The first contact 52 and the second contact 64 are in contact with the workpiece 100, and the contacts will wear. Therefore, the use of wear-resistant materials can delay the wear of the contacts. When the contacts are worn to the point where they cannot be used, they can be replaced with new ones. In addition, the contacts are preferably in point contact with the outer diameter of the workpiece, so as to avoid the contacts affecting the processing accuracy. The front side of the contacts can be designed in the form of a large arc.

[0048] Preferably, the bottom support assembly 6 also includes a fixing plate 66 and a rotating shaft tightening screw 67, and the fixing plate 66 is fixedly connected to the base 1. In this case, the rotating shaft 62 passes through the fixing plate 66 and is fixed by the rotating shaft tightening screw 67, rather than being directly connected to the base 1. The rotating shaft tightening screw 67 can radially press the rotating shaft 62.

[0049] The bottom support assembly 6 may also include a rolling bearing 68 so that the push rod piece 61 can smoothly rotate around the rotating shaft 62. The inner ring of the rolling bearing 68 is sleeved on the rotating shaft 62. The inner ring can be pressed on the rotating shaft 62 by an inner ring pressing gasket 681 and fixed by an inner ring screw 69. The outer ring is installed in the push rod piece 61 and can be pressed by an outer ring pressing screw 682 to rotate with the push rod piece 61. When the hydraulic cylinder 2 is started, the two preload fine-tuning mechanisms 3 are driven simultaneously with the fine-tuning mechanism mounting seat 4 to make the two push rods move horizontally at the same time. One push rod directly drives the first contact 52 to move, and the other push rod pushes the push rod piece 61 to rotate after translating a certain distance, thereby driving the second contact 64 to rotate. The two contacts support the workpiece 100 at the same time.

[0050] It should be pointed out that when the operator uses the center stand of the utility model to perform grinding operations on a grinding machine, the operator can use the hydraulic cylinder 2 and the two preload fine-tuning mechanisms 3 in combination for adjustment, that is, first use the hydraulic cylinder 2 to coarsely adjust the preload, and then use the preload fine-tuning mechanism 3 to manually fine-tune it.

[0051] In an exemplary embodiment of the present utility model, the center frame also includes a guide mechanism, which is used to guide the workpiece support mechanism and includes a linear bearing 71 mounted to the base 1 and a guide rod 72 passing therethrough, and the guide rod 72 is fixedly connected to the fine-tuning mechanism mounting seat 4. When the hydraulic cylinder 2 is required to provide a preload, the hydraulic cylinder 2 works, and its piston rod drives the fine-tuning mechanism mounting seat 4 and the two preload fine-tuning mechanisms 3 and the guide rod 72 connected thereto to move synchronously, and the guide rod 72 slides in the linear bearing 71 mounted to the base 1 and is guided, so that the fine-tuning mechanism mounting seat 4 is also guided, thereby ensuring the linear and smooth movement of the ejector rod 35 and improving the positioning accuracy of the workpiece 100.

[0052] The guide mechanism may further include a bearing mounting seat 73, the bearing mounting seat 73 is connected to the base 1, and the linear bearing 71 is accommodated in the bearing mounting seat 73. This method can simplify the structure of the base 1 and facilitate the processing of the base 1. In addition, the guide mechanism can be arranged one at each of the upper and lower ends of the fine-tuning mechanism mounting seat 4, that is, arranged close to the two preload fine-tuning mechanisms 3. The linear bearing 71 can be pressed against the bearing mounting seat 73 using a bearing clamping screw 74 to prevent the linear bearing 71 from moving.

[0053] In some embodiments, the center frame also includes a detection unit, which includes a sensor 75 and a sensor bracket 76. The sensor bracket 76 is installed on the base 1 and can be installed by screws. The sensor 75 is connected to the sensor bracket 76 for determining the position of the top rod 35 through position detection.

[0054] The detection unit may further include a sensing bracket 77, which is connected to the fine-tuning mechanism mounting base 4 and moves with the fine-tuning mechanism mounting base 4 to determine the position of the push rod 35 by detecting the position of the sensing bracket 77. The sensing bracket 77 may be made by bending a thin plate, one end of which is fixedly connected to the fine-tuning mechanism mounting base 4 by screws, and the other end is located directly above the sensor 75.

[0055] Now the process of grinding a workpiece using the center frame for a grinding machine of the utility model is described:

[0056] Step 1, install the center frame on the grinding machine workbench and connect the hydraulic pipeline of the center frame;

[0057] Step 2: Install the qualified workpiece on the grinding machine, install two dial gauges at the position where the workpiece is tightened, confirm that the dial gauge has a range in both the + / - direction and set the pointer to zero;

[0058] Step 3, start the hydraulic cylinder 2, so that the first contact 52 and the second contact 64 are pressed against the outer diameter of the workpiece, and adjust the two preload fine-tuning mechanisms 3;

[0059] Step 4, rotating the workpiece to control the runout of the dial indicator within the required range;

[0060] Step 5, remove the qualified workpiece and the dial indicator, install the blank and start grinding;

[0061] Step 6, check the machining accuracy of the blank. If the accuracy is qualified, it will be processed normally. If it is not qualified, repeat steps 2 to 4 and readjust the runout requirements of the micrometer until the machining accuracy of the workpiece is qualified.

[0062] As described above, through the utility model, the preload force of the workpiece can be adjusted by combining the hydraulic cylinder and the preload force fine-tuning mechanism, wherein, when the hydraulic cylinder is used to adjust the preload force, the two preload force fine-tuning mechanisms are driven simultaneously along with the fine-tuning mechanism mounting seat to make the two push rods move horizontally at the same time, one push rod directly drives the first contact to move, and the other push rod pushes the push rod piece to rotate after being translated a certain distance, thereby driving the second contact to rotate, and the two contacts support the workpiece at the same time. Therefore, the utility model does not require high-precision matching components to ensure synchronous movement in two directions, and the design accuracy requirement is low; when the preload force fine-tuning mechanism is used to manually fine-tune the preload force, the adjusting screw therein can be screwed to move the push rod left and right through the compression spring, and then the adjusting screw can be locked with a locking nut. Therefore, in addition to realizing preload force adjustment through the hydraulic cylinder, the utility model can also manually fine-tune the preload force through the preload force fine-tuning mechanism, and has strong applicability.

[0063] The features mentioned and / or shown in the above description of the exemplary embodiments of the utility model can be combined in the same or similar manner into one or more other embodiments, combined with the features in other embodiments or replace the corresponding features in other implementations. The technical solutions obtained by these combinations or replacements should also be deemed to be included in the protection scope of the utility model.

Claims

1. A center frame for a grinding machine, characterized in that: It includes a base, a hydraulic cylinder, two preload fine-tuning mechanisms, a fine-tuning mechanism mounting seat and a workpiece supporting mechanism; The base is used to support the hydraulic cylinder, the preload fine-tuning mechanism and the workpiece supporting mechanism; The hydraulic cylinder is mounted on the base to provide driving force for the workpiece support mechanism, and the piston rod of the hydraulic cylinder is connected to the fine-tuning mechanism mounting seat; The two preload fine-tuning mechanisms are arranged in parallel up and down, and each comprises an adjusting rod, a compression spring, an adjusting screw, a locking nut and a push rod, the adjusting rod is horizontally arranged and fixedly connected to the fine-tuning mechanism mounting seat, the compression spring is horizontally accommodated in the adjusting rod, the adjusting screw is axially pressed on one end of the compression spring and locked by the locking nut, and one end of the push rod is in contact with the other end of the compression spring; The workpiece support mechanism includes a side support assembly and a bottom support assembly, The side support assembly includes an anti-rotation rod and a first contact for supporting the side of the workpiece, the first contact is connected to the other end of the top rod of one of the two preload fine-tuning mechanisms located at the top, the anti-rotation rod connects the adjustment rod and the first contact and can move left and right relative to the adjustment rod, The bottom support assembly includes a push rod piece, a rotating shaft, a tension spring and a second contact for supporting the bottom of the workpiece and connected to the push rod piece, the push rod piece is in contact with the other end of the push rod of one of the two preload fine-tuning mechanisms located at the bottom, the rotating shaft is fixed to the base, the push rod piece is mounted on the rotating shaft and can rotate around the rotating shaft under the action of the push rod, one end of the tension spring is fixed to the base, and the other end is fixed to the push rod piece to keep the push rod piece in place when the push rod piece is not rotated.

2. The center stand for a grinding machine according to claim 1, characterized in that: It also includes a guiding mechanism, which is used to guide the workpiece supporting mechanism and includes a linear bearing installed on the base and a guide rod passing through it, and the guide rod is fixedly connected to the fine-tuning mechanism mounting seat.

3. The center stand for a grinding machine according to claim 2, characterized in that: The guide mechanism further comprises a bearing mounting seat, the bearing mounting seat is connected to the base, and the linear bearing is accommodated in the bearing mounting seat.

4. The center stand for a grinding machine according to claim 2, characterized in that: The guide mechanism is arranged at each of the upper and lower ends of the fine-tuning mechanism mounting seat.

5. The center stand for a grinding machine according to claim 1 or 2, characterized in that: The bottom support assembly also includes a fixing plate and a fixing plate tightening screw. The fixing plate is fixedly connected to the base. The rotating shaft passes through the fixing plate and is fixed by the fixing plate tightening screw.

6. The center stand for a grinding machine according to claim 1 or 2, characterized in that: The bottom support assembly also includes a rolling bearing, the inner ring of the rolling bearing is sleeved on the rotating shaft, and the outer ring is installed in the top rod sheet.

7. The center stand for a grinding machine according to claim 1 or 2, characterized in that: It also includes a detection unit, which includes a sensor and a sensor bracket. The sensor bracket is installed on the base, and the sensor is connected to the sensor bracket to determine the position of the push rod through position detection.

8. The center stand for a grinding machine according to claim 7, characterized in that: The detection unit further comprises a sensing bracket, which is connected to the fine-tuning mechanism mounting seat so as to determine the position of the ejector rod by detecting the position of the sensing bracket.

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