A fixture for machining castings

Abstract

The present application discloses a fixture for machining castings, belonging to the technical field of casting fixtures. It mainly includes a base plate, the bottom surface of which is provided with an embedded groove, and the base plate is provided with four groups of threaded holes; a locking mechanism, which is connected in the threaded holes; a cylinder, and a lifting plate is installed at the output end of the cylinder; a rack, which is composed of a smooth area and meshing teeth, a first support frame is installed on the base plate, and a support rod is connected to the bearing on the first support frame, and a first bevel gear is installed on the support rod, and a first gear is installed on the support rod; a first support ring, and a first rotating shaft is installed on the locking screw, and the upper end of the first support ring is movably sleeved on the first rotating shaft, and the first support ring bearing is installed with a second bevel gear; the side of the first rotating shaft has a boss. The fixture for machining castings of the present application converts the linear motion of the cylinder into a rotational motion to complete the all-round clamping of the workpiece, and provide stable clamping for the processing operation.

Description

Technical Field

[0001] The present application relates to the technical field of casting fixtures, and in particular to a fixture used for machining castings. Background Art

[0002] Casting cutting refers to the use of cutting tools (such as cutters) to remove excess material from the surface of the casting to obtain dimensional accuracy, shape accuracy and surface quality that meet the design requirements. Its main purpose is to eliminate the dimensional errors, shape defects, surface roughness and other problems generated during the casting process, so that the casting can meet the requirements of assembly and use;

[0003] Cutting of castings is a common processing method in metal processing. Traditional casting processing generally undergoes aging treatment after casting and rough processing, and limits the degree of freedom according to the simple six-point rule during clamping. When processing the inclined surface, the shape is generally milled into place first, and then a fixture with an inclined surface is made, and then the inclined surface is processed by secondary clamping. This clamping and processing method does not take into account the errors caused by processing deformation and positioning errors, and does not conduct a rational inspection of the process flow, which leads to many problems such as difficulty in workpiece processing, low processing efficiency, and low yield rate. Therefore, it is necessary to provide a fixture for casting machining to solve the above problems.

[0004] It should be noted that the above information disclosed in this background technology section is only for understanding the background technology of the present application concept, and therefore, it may contain information that does not constitute the prior art. Summary of the invention

[0005] Based on the above problems existing in the prior art, the problem to be solved by the present application is: to provide a fixture for machining castings, to complete the all-round clamping operation of the workpiece, and to provide stable clamping and positioning guarantee for related machining operations.

[0006] The technical solution adopted by the present application to solve its technical problem is: a fixture for machining castings, characterized in that it includes: a base plate, the bottom surface of which is provided with an embedded groove, and the base plate is provided with four groups of threaded holes; a locking mechanism, which is connected in the threaded holes, and the locking mechanism is composed of a locking seat, an eccentric sleeve and a locking screw; a cylinder, which is installed in the embedded groove, and the output end of the cylinder is installed with a lifting plate; a rack, which is installed on the lifting plate, and the rack is composed of a smooth area and meshing teeth, and a first support frame is installed on the base plate, The bearing on the first support frame is connected to a support rod, a first bevel gear is installed on the support rod, a first gear is installed on the support rod, and the first gear is in a smooth area; a first support ring, the first support ring is installed on the base plate, a first rotating shaft is installed on the locking screw, the upper end of the first support ring is movably sleeved on the first rotating shaft, a second bevel gear is installed on the bearing of the first support ring, and the first bevel gear is meshed with the second bevel gear; a side surface of the first rotating shaft has a boss, and the second bevel gear is slidably sleeved on the boss.

[0007] Furthermore, a chassis is mounted on the lifting plate, a bearing on the chassis is connected to a seat body, a rotating rod is mounted on the seat body, a spring is mounted on the seat body, a fixing seat is mounted on the bottom plate, the fixing seat is located at the upper end of the seat body, and one end of the spring is in contact with the bottom surface of the fixing seat;

[0008] The fixing seat is movably sleeved on the rotating rod, a pressing piece is installed on the top of the rotating rod, and a silicone pad is installed on the bottom of one end of the pressing piece.

[0009] Furthermore, a spiral groove is provided on the inner wall of the fixing seat, and the spiral groove has a starting groove. A sliding block is installed on the outer wall of the rotating rod. A first spiral groove is connected to the starting groove, and the groove direction of the first spiral groove is gradually increased and opened along the inner diameter of the fixing seat.

[0010] Furthermore, a flat groove is connected to the first screw groove, and the flat groove is opened along the inner diameter of the fixing seat.

[0011] Furthermore, a cover is bolted onto the base plate.

[0012] Furthermore, a descending groove is connected to the flat groove, and the descending groove is opened along the inner diameter of the fixed seat. The rotation direction of the descending groove is a gradually descending trend. A circular groove is opened on the bottom surface of the seat body, and the depth of the circular groove gradually increases from shallow to deep.

[0013] Furthermore, a rotating rod is installed on the chassis, an anti-slip portion is provided on the rotating rod, and a side groove is opened on the side wall of the annular groove. In an initial state, the rotating rod is located at a shallow groove position on the annular groove.

[0014] Furthermore, the locking mechanism is made of steel.

[0015] Furthermore, six groups of mounting holes are provided on the bottom plate, a material discharge trough is provided on the bottom plate, a right-angle side surface of the material discharge trough is opened, and three groups of right-angle positioning reference surfaces are formed, namely a bottom surface and two side surfaces, and a workpiece is placed on the positioning reference surface;

[0016] The three groups of threaded holes are arranged transversely on the same horizontal line and are located on a side close to the long side of the workpiece, while the remaining group of threaded holes is located on one side of the short side of the workpiece.

[0017] Furthermore, the locking seat has a plane on its outer circle, a boss on its bottom surface, and an inner hole. The outer cylinder and inner cylinder of the eccentric sleeve are offset by 0.8 mm, a first rectangular flat wire is provided on the inner cylinder, and a second rectangular flat wire is provided on the outer circle of the locking screw.

[0018] The beneficial effect of the present application is that the clamp provided by the present application for machining castings realizes a multi-directional and stable clamping of the workpiece through the cooperation of the driving mechanism and the locking mechanism. The lifting plate is driven by the cylinder to move, and the upward and rotating movement of the rotating rod first restricts the top surface of the workpiece, and then the locking screw is driven to tighten in the threaded hole to clamp the long side of the workpiece through the gear bevel gear transmission; in this process, the top surface is always pressed, which effectively avoids the displacement and shaking of the workpiece during the clamping process, ensures the accurate positioning of the workpiece during processing, greatly improves the stability of the clamping, and is conducive to ensuring the processing accuracy.

[0019] In addition to the above-described purposes, features and advantages, the present application also has other purposes, features and advantages. The present application will be further described in detail with reference to the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings constituting part of the present application are used to provide a further understanding of the present application. The exemplary embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0021] Figure 1 It is an overall schematic diagram of a fixture used for machining castings in the present application;

[0022] Figure 2 for Figure 1 Schematic diagram of the local structure;

[0023] Figure 3 for Figure 1 A schematic diagram of the locking mechanism structure;

[0024] Figure 4 for Figure 2 Schematic diagram of the local structure;

[0025] Figure 5 for Figure 4 Schematic diagram of the local structure;

[0026] Figure 6 for Figure 5 A magnified schematic diagram of the middle A area;

[0027] Figure 7 for Figure 4 A magnified schematic diagram of the middle B area;

[0028] Figure 8 for Figure 5 Schematic diagram of the bottom structure;

[0029] Among them, the reference numerals in the figure are:

[0030] 1. Bottom plate; 101. Mounting hole; 102. Material discharge trough; 103. Threaded hole; 105. Workpiece; 107. Sealing groove; 108. Oil hole; 109. Rectangular groove; 110. Fixing hole;

[0031] 2. Locking mechanism; 201. Locking screw; 202. Eccentric sleeve; 203. Locking seat;

[0032] 3. Driving mechanism; 301. Cylinder; 302. Lifting plate; 303. Chassis; 304. Seat; 305. Spring; 306. Fixed seat; 307. Spiral groove; 308. First spiral groove; 309. Flat groove; 310. Descending groove; 311. Rotating rod; 314. Holding member; 316. Rack; 318. First supporting frame; 319. First gear; 320. First bevel gear; 321. First rotating shaft; 322. Second bevel gear; 323. First supporting ring; 339. Annular groove; 340. Rotating rod; 342. Cover shell. DETAILED DESCRIPTION

[0033] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0034] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0035] Embodiment 1: This embodiment describes the structure and working principle of a fixture for machining castings, specifically:

[0036] like Figure 1-Figure 3 As shown, the present application provides a fixture for machining castings, the casting is the workpiece 105 in the present application, the workpiece 105 is made of casting material, cast once, and after machining, has an inclined rectangular groove 109, an oil hole 108 and a sealing groove 107 perpendicular to the bottom surface, and a fixing hole 110 for mounting the workpiece 105. Because the workpiece 105 has a high precision, in order to avoid repeated positioning, a specific fixture is used for clamping;

[0037] The fixture comprises a bottom plate 1, six groups of mounting holes 101 are formed on the bottom plate 1, the bottom plate 1 is fixed to the rotary table by connecting screws to the mounting holes 101, and a material discharge trough 102 is formed on the bottom plate 1, a right angle side surface of the material discharge trough 102 is opened, and three groups of right angle positioning reference surfaces (such as Figure 3 ), are respectively a bottom surface and two side surfaces, and a workpiece 105 is placed on the positioning reference surface, and the positioning reference surface is used to place and limit the workpiece 105;

[0038] It should be noted that the rotary table is generally the fourth axis of the machine tool, which can be rotated to any angle according to the needs;

[0039] At the same time, four groups of threaded holes 103 are opened on the bottom plate 1, three of which are arranged horizontally on the same horizontal line and are located on a side close to the long side of the workpiece 105, and the remaining group of threaded holes 103 is located on one side of the short side of the workpiece 105, and a locking mechanism 2 is connected in the threaded holes 103;

[0040] The locking mechanism 2 is made of 45 steel and consists of three parts: a locking seat 203, an eccentric sleeve 202 and a locking screw 201. The locking seat 203 has a plane on its outer circle and a boss on its bottom (such as Figure 6 ), and the locking seat 203 has an inner hole (not shown in the figure), which provides space for the installation of the eccentric sleeve 202, and the eccentric sleeve 202 is tightly nested in the inner hole;

[0041] The outer cylinder and the inner cylinder of the eccentric sleeve 202 are offset by 0.8 mm, and the inner cylinder is also provided with a first rectangular flat wire, which is installed in cooperation with the locking seat 203 (such as Figure 3 ), so that the eccentric sleeve 202 can perform a specific rotational motion in the locking seat 203, and the relative position and motion relationship between the two can be accurately defined;

[0042] At the same time, the outer circle of the locking screw 201 is provided with a second rectangular flat wire (such as Figure 3 ), the second rectangular flat wire enables the locking screw 201 to be accurately installed in the eccentric sleeve 202, thereby establishing a close mechanical connection relationship between the three;

[0043] When the workpiece 105 needs to be locked, the operator rotates the locking screw 201. Since the locking screw 201 is tightly connected to the eccentric sleeve 202 through the second rectangular flat wire, the second rectangular flat wire plays a role in force transmission and motion constraint during the rotation process, so that the rotational motion of the locking screw 201 can be accurately converted into the synchronous rotational motion of the eccentric sleeve 202.

[0044] As the eccentric sleeve 202 rotates, its offset outer cylinder and inner cylinder structure begin to work. Since the eccentric sleeve 202 is installed in the locking seat 203, the rotation of the eccentric sleeve 202 will generate an eccentric force, which will be transmitted to the locking seat 203. Specifically, the rotation of the eccentric sleeve 202 will cause the locking seat 203 to produce a slight displacement and angle change, thereby driving the plane on the outer circle of the locking seat 203 to gradually approach and finally press against the side of the workpiece 105.

[0045] In order to control the machining accuracy of the workpiece 105, the machining process is as follows:

[0046] The first step: forming a blank of the workpiece 105 by a casting process;

[0047] This step provides a basic shape for subsequent processing, but there is internal stress inside the workpiece 105 after casting, and the shape accuracy and surface quality cannot meet the final use requirements, and subsequent processing is required;

[0048] Step 2: Place the cast workpiece 105 flat on the aging rack, keep a proper distance to avoid collision, and then push it into the furnace, and move as slowly as possible. The aging furnace heats up to 550-600℃ at a rate of 100℃ / hour, then stops heating, keeps at this temperature for 4-6 hours, then cools down at a rate of 50℃ / hour, stops cooling at 200℃, turns off the power, and pulls the aging rack out slowly to air cool to room temperature.

[0049] The purpose of this aging treatment is to initially release the internal stress generated during the casting process and reduce the risk of deformation of the workpiece 105 during subsequent processing.

[0050] Step 3: Perform semi-finishing milling on the workpiece 105 after aging treatment, and leave a single-side allowance of 1 mm;

[0051] This reserves a certain amount of processing for the subsequent fine milling process, and can also further correct the external dimensions of the workpiece 105 to make it closer to the final design requirements. In the process, some casting surface defects and uneven allowances can be removed.

[0052] Step 4: Repeat the first aging treatment steps;

[0053] The internal stress generated during the semi-finishing milling process is further released to ensure the stability of the workpiece 105 and prevent deformation in subsequent processing.

[0054] Step 5: Perform fine milling on the four sides of the workpiece 105 to achieve the accuracy requirement of no allowance, and leave an allowance of 0.3mm on the bottom surface to prepare for subsequent fine grinding of the bottom surface, and leave an allowance of 0.5mm on the reference surface for subsequent fine milling;

[0055] Through precise milling processing, the outer dimensions and surface quality of the workpiece 105 are significantly improved, reaching a higher level of accuracy and meeting the requirements of the design drawings.

[0056] Step 6: Perform aging treatment again;

[0057] After the previous fine milling process, a certain amount of internal stress will be generated inside the workpiece 105. The internal stress is further eliminated through the aging treatment, thereby ensuring the dimensional stability of the workpiece 105 and reducing the possibility of deformation of the final product.

[0058] Step 7: Fine grinding is performed on the bottom surface of the workpiece 105 so that the bottom surface flatness requirement is not greater than 0.003 mm;

[0059] The high-precision bottom surface flatness is obtained through the grinding process, which provides an accurate positioning basis for subsequent processing steps based on the bottom surface, thereby ensuring the processing accuracy and assembly accuracy of the entire workpiece 105.

[0060] The plane, rectangular groove 109, fixing hole 110 and sealing groove 107 of the workpiece 105 are milled. The bottom surface and two side surfaces of the workpiece 105 are used as positioning references by a machining fixture. The other two side surfaces are pressed by a locking mechanism 2. The plane is first milled, and then the rectangular groove 109 and the sealing groove 107 are milled in sequence by rotating the rotary table to the required angle. In this process, since the plane and the inclined surface are clamped at one time, the consistency of different workpieces 105 is guaranteed to be good. At the same time, the flatness of the plane and the inclined surface is required to be no greater than 0.005mm, and the angle error is ≤5". Through the precise machining process and the coordination of the fixture, high-precision machining of the complex structure of the workpiece 105 is achieved, meeting the requirements of the sealing performance and assembly accuracy of the workpiece 105 in actual use.

[0061] Embodiment 2: Since there are many locking points, if the staff locks them one by one, the labor intensity of the staff will undoubtedly increase in the processing of a large number of workpieces 105. In order to solve this problem, this embodiment provides a linkage locking structure, specifically:

[0062] In this embodiment, since the four sets of locking mechanisms 2 have the same structure, one set of locking mechanisms 2 is taken as an example to explain the linkage locking structure in detail. Figure 2 The figure is subject to the leftmost locking mechanism 2 as an example for explanation;

[0063] like Figure 2 and 4 As shown, an embedded groove (not shown in the figure) is provided on the bottom surface of the bottom plate 1, and a cylinder 301 is fixedly installed inside the embedded groove, and a lifting plate 302 is fixedly installed at the output end of the cylinder 301, so that the lifting plate 302 can reciprocate in the vertical direction under the drive of the cylinder 301;

[0064] like Figure 4 and Figure 6-Figure 7 As shown, a plurality of driving mechanisms 3 are arranged on the lifting plate 302, and the plurality of driving mechanisms 3 correspond to the locking mechanisms 2 at different positions, so as to synchronously lock or loosen the locking mechanisms 2. Specifically, the driving mechanism 3 comprises a rack 316 fixedly mounted on the lifting plate 302, and a first support frame 318 is fixedly mounted on the bottom plate 1, and the first support frame 318 has a support rod connected with a bearing, and a first gear 319 is fixedly mounted on the support rod, and the first gear 319 is suitable for meshing and driving connection with the rack 316, so that during the movement of the lifting plate 302, the rack 316 can be driven to move synchronously, and the first gear 319 can be driven to rotate synchronously, and a first bevel gear 320 is fixedly mounted on the support rod, and the first bevel gear 320 is suitable for rotating synchronously with the first gear 319;

[0065] At the same time, a first support ring 323 is fixedly installed on the bottom plate 1, and a first rotating shaft 321 is fixedly installed on the locking screw 201. The upper end of the first support ring 323 is movably sleeved on the first rotating shaft 321, and a second bevel gear 322 is installed on a bearing. The second bevel gear 322 is meshed with the first bevel gear 320, so that the second bevel gear 322 can rotate under the drive of the first bevel gear 320;

[0066] The side of the first rotating shaft 321 has a boss, and the second bevel gear 322 is slidably sleeved on the boss, so that the second bevel gear 322 can drive the first rotating shaft 321 to rotate through the boss, and then drive the locking screw 201 to rotate, so as to drive the locking seat 203 to eccentrically tighten, thereby achieving the purpose of locking the workpiece 105;

[0067] In this embodiment, because the second bevel gear 322 is slidably connected to the first rotating shaft 321 through the boss, the meshing state of the second bevel gear 322 and the first bevel gear 320 will not be affected by the vertical movement of the first rotating shaft 321 during the locking and unlocking process of the locking screw 201;

[0068] In summary, when multiple sets of locking mechanisms 2 need to be locked synchronously, it is only necessary to start the cylinder 301 to drive the lifting plate 302 to move upward, and through the action of multiple sets of driving mechanisms 3, the corresponding locking screws 201 can be rotated, and vice versa, multiple sets of locking mechanisms 2 can be unlocked synchronously;

[0069] In order to better lock the workpiece 105, the locking mechanisms 2 on both sides can be locked first, and then the locking mechanism 2 in the middle can be locked. The above operation can change the locking order of different locking mechanisms 2, so as to achieve a better control locking effect;

[0070] In order to achieve the above purpose, the rack 316 can be improved. Specifically, the meshing teeth of the rack 316 can be set to the same length, so that multiple sets of locking mechanisms 2 can achieve the purpose of complete locking. At the same time, a smooth section is provided on the rack 316, and the smooth section does not mesh with the first gear 319. Therefore, even if the rack 316 moves vertically, the first gear 319 cannot be driven to rotate in the smooth section area, and thus it will not contribute to the locking of the locking mechanism 2.

[0071] Therefore, different locking sequences can be achieved by matching meshing teeth of the same length and smooth sections of different lengths and positions to meet different locking requirements.

[0072] Embodiment three:

[0073] During the process of locking the workpiece 105, the workpiece 105 is easily moved upward because of the locking support at the bottom, which may cause the workpiece 105 to tilt after the locking is completed;

[0074] In order to solve the above problems, Figure 4-Figure 7 As shown, a base plate 303 is fixedly mounted on the lifting plate 302, a seat body 304 is bearing-connected on the base plate 303, and a rotating rod 311 is fixedly mounted on the seat body 304;

[0075] A spring 305 is installed on the seat body 304, and a fixing seat 306 is fixedly installed on the bottom plate 1. The fixing seat 306 is located at the upper end of the seat body 304, and one end of the spring 305 is in contact with the fixing seat 306. At the same time, the fixing seat 306 is movably sleeved on the rotating rod 311, and a pressing member 314 is fixedly installed on the top of the rotating rod 311. A silicone pad (not shown in the figure) is fixedly installed at the bottom of one end of the pressing member 314.

[0076] In the initial state, the spring 305 is in a naturally extended state, and its elastic force maintains the relative balance of the entire mechanism. Under the elastic force of the spring 305, the holding member 314 is in a relatively low position and is on one side of the workpiece 105. When the cylinder 301 is started, the output end of the cylinder 301 pushes the lifting plate 302 to move upward. Since the lifting plate 302 is fixedly connected to the chassis 303, the chassis 303 moves upward with the lifting plate 302, and drives the rotating rod 311 to move upward, so as to push the holding member 314 to move upward, and at the same time squeeze the spring 305.

[0077] In order to enable the workpiece 105 to be pressed vertically during the upward movement of the pressing member 314, as shown in FIG. Figure 4-Figure 7 As shown, a spiral groove 307 is opened on the inner wall of the fixing seat 306, and the spiral groove 307 has an initial starting groove. At the same time, a slider adapted to the width of the spiral groove 307 is fixedly installed on the outer wall of the rotating rod 311, and a first spiral groove 308 is opened in communication with the starting groove. The groove direction of the first spiral groove 308 is gradually increased and opened along the inner diameter of the fixing seat 306;

[0078] It should be noted that the slider is initially located at the starting slot. When the slider moves from the starting slot to the first screw slot 308, due to the special shape of the first screw slot 308 (gradually rising and spiral), the slider will not only rise in the vertical direction, but will also be guided by the spiral of the slot during its movement. The spiral guidance will give the slider a tangential force, so that the slider drives the rotating rod 311 to rotate. Since the slider is fixed on the rotating rod 311, the rotating rod 311 will move with the movement of the slider. In the process of the slider sliding from the starting slot to the high point of the first screw slot 308, the rotating rod 311 achieves a 45-degree rotation while moving upward. At this time, the rotating rod 311 drives the holding member 314 to rotate 45 degrees while moving upward. At this time, the silicone pad at the bottom of the holding member 314 is in close contact with the upper surface of the workpiece 105, so as to exert a certain downward squeezing force on the workpiece 105.

[0079] A flat groove 309 tending to be arranged horizontally is connected to the first screw groove 308, and the flat groove 309 is also opened along the inner diameter of the fixing seat 306. As the output end of the cylinder 301 continues to push, the rotating rod 311 slides along the high point of the first screw groove 308 to the flat groove 309 through the slider, and then slides from the flat groove 309. At this time, the rotating rod 311 completes a 90-degree rotation in the horizontal direction again, that is, drives the holding member 314 to rotate 90 degrees in the horizontal direction. At this time, since the distance between the holding member 314 and the top surface of the workpiece 105 remains unchanged, the holding restriction on the top surface of the workpiece 105 can be continuously maintained;

[0080] When locking the workpiece 105, the cylinder 301 is started to push the lifting plate 302 to move upward, so as to drive the rotating rod 311 to slide from the starting groove to the high point of the first screw groove 308 through the slider. The rotating rod 311 realizes a 45-degree rotation while moving upward, and at the same time drives the silicone pad at the bottom of the pressing member 314 to contact the upper surface of the workpiece 105, so as to firstly limit the workpiece 105 downward;

[0081] Then, as the telescopic end of the cylinder 301 continues to extend, the rotating rod 311 continues to slide along the high point of the first screw groove 308 to the flat groove 309 through the slider, and slides in the flat groove 309. At this time, the rotating rod 311 completes a 90-degree rotation relative to the horizontal direction again, and the holding member 314 maintains a horizontal restriction on the top surface of the workpiece 105. During the process again, the output end of the cylinder 301 synchronously pushes the lifting plate 302 to make a vertical linear motion upward. Since the lifting plate 302 is fixed with a rack 316, as the lifting plate 302 rises, the rack 316 moves upward synchronously. Since the first gear 319 is in the position of the smooth section of the rack 316 in the initial state, the start of the cylinder 301 can first drive the holding member 314 to rotate 45 degrees and make the silicone pad contact with the top surface of the workpiece 105;

[0082] As the telescopic end of the cylinder 301 continues to extend, at this time, due to the support rod bearing connection of the first support frame 318 on the bottom plate 1, the first gear 319 fixed on the support rod is in contact and meshing with the rising rack 316, and the rack 316 drives the first gear 319 to rotate, and the first bevel gear 320 fixed on the support rod rotates synchronously with the first gear 319, and the first bevel gear 320 is meshed with the second bevel gear 322, thereby driving the second bevel gear 322 to rotate, and the second bevel gear 322 drives the first rotating shaft 321 to rotate through the sliding sleeve connection with the side boss of the first rotating shaft 321, and the first rotating shaft 321 drives the locking screw 201 to rotate synchronously, and the locking screw 201 rotates to make the locking seat 203 eccentrically tightened, and finally the workpiece 105 is locked;

[0083] That is, during the locking process, the two sides of the workpiece 105 are clamped together, and the pressing member 314 simultaneously keeps the top surface of the workpiece 105 restricted, thereby ensuring the stability of the clamping of the workpiece 105;

[0084] The motion transmission of the entire mechanism is realized by starting the cylinder 301. First, the movement of the rotating rod 311 (including upward movement and rotation) is used to limit the top surface of the workpiece 105 by the holding member 314. Subsequently, the locking screw 201 is driven to rotate synchronously through the gear bevel gear transmission system. This realizes the synchronous clamping of both sides of the workpiece 105, ensuring that the top surface of the workpiece 105 is always restricted by the holding member 314 during the entire clamping process, and firmly clamping the workpiece 105 from multiple dimensions, ensuring the accurate positioning and stability of the workpiece 105 during the clamping process, avoiding the displacement and shaking of the workpiece 105 during the clamping process, and improving the processing accuracy and reliability of the clamping process.

[0085] A cover shell 342 is bolted onto the base plate 1 , and the cover shell 342 is used to shield the driving mechanism 3 from dust.

[0086] Embodiment 4:

[0087] When the cylinder 301 is started to drive the rotating rod 311 to slide in the spiral groove 307 through the slider to realize a rotation of 135 degrees, the slider is in the position of the flat groove 309, and the rotating rod 311 rotates 45 degrees to press the surface of the workpiece 105 until the rotating rod 311 rotates 90 degrees again, and still keeps pressing the surface of the workpiece 105, and when the rotating rod 311 rotates 135 degrees, the pressing member 314 slides over the workpiece 105, but because the spiral groove 307 tends to rise gradually, when the rotating rod 311 rotates 135 degrees, the horizontal height of the pressing member 314 and the bottom plate 1 is greater than the horizontal height of the top surface of the workpiece 105 and the bottom plate 1, thereby affecting the subsequent processing of the workpiece 105;

[0088] like Figure 5 and Figure 8 As shown, different from the above-mentioned embodiment, a descending groove 310 is connected to the flat groove 309 in the fixing seat 306, and the descending groove 310 is opened along the inner diameter of the fixing seat 306, and the rotation direction of the descending groove 310 is a gradually descending trend, and the seat body 304 is no longer connected to the bearing of the chassis 303, and at the same time, a circular groove 339 is opened on the bottom surface of the seat body 304, and the groove depth of the circular groove 339 is from shallow to deep;

[0089] It should be noted that when the rotating rod 311 slides from the flat groove 309 to the descending groove 310 through the slider, the rotating rod 311 completes a 180-degree rotation;

[0090] A rotating rod 340 is fixedly mounted on the chassis 303, and an anti-slip portion is provided on the rotating rod 340. A side groove adapted to the anti-slip portion is provided on the side wall of the annular groove 339, and in the initial state, the rotating rod 340 is located at a shallow groove position of the annular groove 339;

[0091] When the cylinder 301 starts to work, it pushes the rotating rod 311 to move upward. During this process, the rotating rod 311 cooperates with the spiral groove 307 through the slider on its outer wall and starts to rotate.

[0092] As the telescopic end of the cylinder 301 continues to extend, the rotating rod 311 will continue to move. When the telescopic end of the cylinder 301 moves to the extreme position, the rotating rod 311 synchronously completes a 135-degree rotation. While the rotating rod 311 rotates, the spring 305 will be compressed. At the same time, the seat body 304 will move synchronously. Since the annular groove 339 on the bottom surface of the seat body 304 cooperates with the rotating rod 340 on the chassis 303, the seat body 304 will rotate around the rotating rod 340. As the rotating rod 311 moves, the rotating rod 340 will slide from the shallow groove position of the annular groove 339 to the deep groove position, because the position of the rotating rod 340 is fixed on the chassis 303, and there is a certain distance between the deep groove of the annular groove 339 and the top of the rotating rod 340.

[0093] When the rotating rod 340 slides toward the deep groove, under the elastic force of the spring 305, the seat body 304 will be subjected to an elastic reaction force, and this reaction force will cause the rotating rod 311 to slide from the flat groove 309 to the descending groove 310 through the slider, and finally the holding member 314 will follow the movement of the rotating rod 311, so that the horizontal height of the holding member 314 and the bottom plate 1 is less than the horizontal height of the top surface of the workpiece 105 and the bottom plate 1, thus ensuring that the holding member 314 will not affect the subsequent processing of the workpiece 105, leaving enough space for the subsequent processing operations, avoiding the interference caused by the holding member 314 being in a higher position when the workpiece 105 is subjected to subsequent processing operations such as milling, drilling, and grinding, thereby ensuring the smooth progress of the processing process;

[0094] A connecting groove (not shown in the figure) is connected to the descending groove 310. The connecting groove is opened along the inner diameter of the fixing seat 306 and shows a gradually descending trend. The connecting groove is connected to the starting groove, and the starting position of the connecting groove is higher than the starting position of the starting groove.

[0095] Therefore, when the workpiece 105 is processed, the telescopic end of the cylinder 301 is reset, and the rotating rod 311 is synchronously driven by the telescopic end of the cylinder 301. The rotating rod 311 slides from the descending groove 310 to the connecting groove through the slider, and then slides from the connecting groove to the starting groove. At this time, the holding member 314 completes the rotation of 180 degrees again, and the rotating rod 311 rotates and gradually descends, so that the slider on the rotating rod 311 returns to the starting groove, so as to synchronously drive the linkage unit and the transmission unit to move synchronously to restore the initial state.

[0096] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A fixture for machining castings, characterized in that: include: A bottom plate (1), the bottom surface of the bottom plate (1) being provided with an embedded groove, and the bottom plate (1) being provided with four groups of threaded holes (103); A locking mechanism (2), the locking mechanism (2) being connected in the threaded hole (103), the locking mechanism (2) being composed of a locking seat (203), an eccentric sleeve (202) and a locking screw (201); A cylinder (301), the cylinder (301) is installed in the embedded groove, and a lifting plate (302) is installed at the output end of the cylinder (301); A rack (316), the rack (316) being mounted on the lifting plate (302), a first support frame (318) being mounted on the bottom plate (1), a support rod being connected to a bearing on the first support frame (318), a first bevel gear (320) being mounted on the support rod, and a first gear (319) being mounted on the support rod; a first support ring (323), the first support ring (323) being mounted on the base plate (1), the locking screw (201) being mounted with a first rotating shaft (321), the upper end of the first support ring (323) being movably sleeved on the first rotating shaft (321), the first support ring (323) being mounted with a second bevel gear (322) on a bearing, the first bevel gear (320) being meshed with the second bevel gear (322); The side surface of the first rotating shaft (321) is provided with a boss, and the second bevel gear (322) is slidably sleeved on the boss; The lifting plate (302) is provided with a chassis (303), a bearing on the chassis (303) is connected to a seat body (304), a rotating rod (311) is provided on the seat body (304), a spring (305) is provided on the seat body (304), a fixing seat (306) is provided on the bottom plate (1), the fixing seat (306) is located at the upper end of the seat body (304), and one end of the spring (305) is in contact with the bottom surface of the fixing seat (306); The fixing seat (306) is movably sleeved on the rotating rod (311), a pressing piece (314) is installed on the top of the rotating rod (311), and a silicone pad is installed at the bottom of one end of the pressing piece (314); The inner wall of the fixing seat (306) is provided with a spiral groove (307), the spiral groove (307) has a starting groove, the outer wall of the rotating rod (311) is provided with a sliding block, the starting groove is connected to a first spiral groove (308), the groove direction of the first spiral groove (308) is gradually increased and is provided along the inner diameter of the fixing seat (306); A flat groove (309) is connected to the first screw groove (308), and the flat groove (309) is opened along the inner diameter of the fixing seat (306); The movement of the rotating rod (311) causes the pressing member (314) to restrict the top surface of the workpiece, and the silicone pad at the bottom of the pressing member (314) is in close contact with the upper surface of the workpiece, so as to exert a certain downward pressing force on the workpiece; The locking screw (201) is driven to rotate synchronously through the gear bevel gear transmission system to achieve synchronous clamping of both sides of the workpiece, ensuring that the top surface of the workpiece is always restricted by the holding member (314) during the entire clamping process, firmly clamping the workpiece from multiple dimensions, ensuring accurate positioning and stability of the workpiece during the clamping process, avoiding displacement and shaking of the workpiece during the clamping process, and improving processing accuracy and reliability of the clamping process.

2. A fixture for machining castings according to claim 1, characterized in that: A cover shell (342) is bolted onto the bottom plate (1).

3. A fixture for machining castings according to claim 2, characterized in that: The flat groove (309) is connected to a descending groove (310), which is opened along the inner diameter of the fixed seat (306). The rotation direction of the descending groove (310) is a gradually descending trend. The bottom surface of the seat body (304) is opened with an annular groove (339), and the groove depth of the annular groove (339) is gradually deepened.

4. A fixture for machining castings according to claim 3, characterized in that: A rotating rod (340) is mounted on the chassis (303), and an anti-slip portion is provided on the rotating rod (340). A side groove is provided on the side wall of the annular groove (339). In an initial state, the rotating rod (340) is located at a shallow groove position on the annular groove (339).

5. A fixture for machining castings according to claim 4, characterized in that: The locking mechanism (2) is made of steel.

6. A fixture for machining castings according to claim 5, characterized in that: The bottom plate (1) is provided with six groups of mounting holes (101), the bottom plate (1) is provided with a material discharge trough (102), a right-angled side surface of the material discharge trough (102) is open, and three groups of right-angled positioning reference surfaces are formed, namely a bottom surface and two side surfaces, and a workpiece (105) is placed on the positioning reference surface; The three groups of threaded holes (103) are arranged transversely on the same horizontal line and are located on a side close to the long side of the workpiece (105), while the remaining group of threaded holes (103) is located on one side of the short side of the workpiece (105).

7. A fixture for machining castings according to claim 6, characterized in that: The locking seat (203) has a plane on its outer circle, a boss on its bottom surface, and an inner hole. The outer cylinder of the eccentric sleeve (202) is offset from the inner cylinder by 0.8 mm, a first rectangular flat wire is formed on the inner cylinder, and a second rectangular flat wire is formed on the outer circle of the locking screw (201).

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