Sliding shoe and plunger integrated injection mold with sliding shoe base body automatic closing-up function and injection molding machining method

Abstract

The invention provides a sliding shoe and plunger integrated injection mold with a sliding shoe base body automatic closing-in function and an injection molding machining method. The injection mold comprises an upper mold base plate (1), an upper mold top plate (2), a glue injection opening (3), a sprue bush (4), an upper mold plate (5), an upper mold inclined sliding block (6), an inner mold core upper cover (7), a lower mold plate (8), a lower mold inclined guide block (9), an inner mold inclined sliding block (10), a lower mold plate inclined guide column (11), an inner mold closing-in shape and position clamping plate (12), an inner mold core lower body (13), a lower mold bearing plate (14), an ejector pin (15), a lower mold spacing plate (16), an upper ejector pin plate (17), a lower ejector pin plate (18), a lower mold bottom plate (19), a lower mold base plate (20) and a lower mold guide column (21). The die comprises a lower die guide pillar spring (22), an upper die guide pillar (23), an upper die guide pillar copper sleeve (24) and an inner hexagon screw used for fixed connection. According to the water hydraulic pump sliding shoe plunger composite body machining and manufacturing method, the prominent defects that according to an existing water hydraulic pump sliding shoe plunger composite body machining and manufacturing method, batch machining is difficult, precision is insufficient, the pump suddenly loses efficacy due to insufficient shoe pulling-out force, and the manufacturing method is difficult are overcome, and the manufacturing precision and reliability of a water hydraulic pump are improved; the manufacturing method is optimized, and the water hydraulic pump sliding shoe and plunger composite with good consistency can be automatically produced in batches.

Description

Technical Field

[0001] The invention relates to an injection mold and a processing method, and in particular to a sliding shoe plunger integrated injection mold with a sliding shoe base automatic closing function. Background Art

[0002] In recent years, water hydraulic transmission and control technology has achieved rapid development and has been widely used in real industrial production. Water hydraulic technology has outstanding advantages such as environmental protection, cleanliness, high efficiency, easy use and maintenance, and low operating cost. It is widely used in many fields such as high-pressure fine water mist fire extinguishing system, high-pressure water cleaning and cutting system, buoyancy adjustment system, seawater desalination system, etc.

[0003] As the core component of water hydraulic transmission and control system, the importance of water hydraulic pump is self-evident. At present, three-plunger reciprocating pump is mainly used as the main power component in high-pressure water jet cutting and high-pressure water cleaning with pressure level greater than 21MPa. Its advantages are high pressure level and good reliability, but its disadvantages are also very obvious, such as large size, need for refueling and maintenance, short life of seals that need regular replacement, high price, small flow rate, etc.

[0004] In the medium and high pressure field of 1.6MPa-21MPa, the fully water-lubricated water hydraulic axial piston pump has become the first choice for system applications due to its outstanding advantages such as compact structure, small PV value, convenient manufacturing and processing, compact size and easy installation. For example, the Danish Danfoss series of fresh water pumps, sea water pumps, British WaterHydrulic series of fresh water pumps, water hydraulic axial piston pumps developed by Huazhong University of Science and Technology, pure water pumps developed by Zhejiang University, and water hydraulic pumps of Wuxi Huaxin Company all use the fully water-lubricated axial piston structure, which has become the preferred structure in this technical field.

[0005] Attached Figure 1 This is a typical schematic diagram of the structure of a water hydraulic axial piston pump. As can be seen from the diagram, the principle of the axial piston pump is to drive the sliding shoe piston complex to reciprocate under the action of the swash plate and the return plate, and cooperate with the structure of the distribution plate to achieve the process of water absorption and drainage. In this process, the sliding shoe piston complex is an alternating load during the movement, especially in the high-pressure and low-pressure switching process. Through actual measurement and simulation analysis, in this process, the plunger high-frequency impact on the ball socket part of the sliding shoe can easily cause damage to the sliding shoe, thereby causing overall damage to the high-pressure pump. This performance is a common feature of axial piston pumps, and this feature is also prominent in oil hydraulic pumps.

[0006] Attached Figure 2This is a typical schematic diagram of the structure of the fully water-lubricated axial piston pump slipper plunger complex. In the existing technology, in the fully water-lubricated water hydraulic pump structure, the friction pair composed of hardened stainless steel and carbon fiber reinforced PEEK engineering plastics has become the first choice. Danfoss, WaterHydrulic, Huazhong University of Science and Technology, Zhejiang University, Wuxi Huaxin Company, etc. all adopt this technical solution. There are currently no commercial products such as ceramic materials and other engineering plastic materials, and most of them are mainly used for scientific research. Figure 2 The slide shoe-plunger complex structure shown in the figure has a plunger made of stainless steel metal material, and the sliding shoe inner ball socket of the plunger ball head is made of carbon fiber reinforced PEEK engineering plastic. The reinforced PEEK engineering plastic needs a metal insert as its supporting structure because of its insufficient strength. At the same time, the slide shoe needs to form a friction surface with the inner ring of the swash plate and the return plate respectively. The parts of the slide shoe that rub against the above two components are all made of PEEK engineering plastic reinforced material. Figure 2 It can be seen from the structure that the plunger ball head rotates in the ball socket inside the sliding shoe, and the ball socket inside the sliding shoe drives the plunger ball head to reciprocate. Under the coupling conditions of multiple movements, the stress condition of the ball socket inside the sliding shoe is particularly complex. The carbon fiber reinforced PEEK engineering plastic layer of the ball socket inside the sliding shoe is impacted and broken by the alternating load. The sliding shoe is pulled off, which is the most common fault of the plunger pump. Figure 3 This is a photo of a failure in which the sliding shoe was pulled off during actual construction. Figure 2 The distance D from the bottom end surface of the sliding shoe to the center of the plunger ball is a key dimension for the smooth return coupling motion of the plunger pump. Its position and size directly determine the smoothness of the pump motion and its life.

[0007] In the structure of a fully water-lubricated axial piston pump, the manufacturing of the slipper-piston complex becomes the key to affecting the life of the water hydraulic pump. At present, there are mainly two manufacturing technology solutions for the slipper-piston complex of a fully water-lubricated axial piston pump.

[0008] Attached Figure 4 This is method one, from the attached Figure 4It can be seen that the scheme is to first manufacture and process the metal sliding shoe base, injection-mold and rubber-coated the sliding shoe base, process the outer circle and ball head of the plunger, measure the actual value of the plunger ball head, use the actual value of the plunger ball head as a reference to coordinate and process the ball socket in the sliding shoe base, wrap the ball by a rotation method or wrap the ball by a pressure forming mold closing method, and roll the sliding shoe plunger. The assembly tool and assembly method for the plunger sliding shoe assembly for a hydraulic plunger pump published in CN103143891B and the plunger sliding shoe closing device published in CN210333884U are the above-mentioned rotation method of wrapping the ball, and the plunger sliding shoe closing tool published in CN113664088B is the above-mentioned pressure forming mold closing method. The above method is acceptable in the manufacture of oil pump slipper plunger complexes. In the manufacture of water hydraulic pump slipper plunger complexes with carbon fiber reinforced PEEK engineering plastics as contact friction surfaces, the advantages are that the slipper is a metal closing structure, the plunger slipper has a large pull-off force, and can be used in heavy-load situations. At the same time, the disadvantages are particularly obvious, as follows: Due to the low density and viscosity of water, the clearance for the same leakage is much smaller than that of oil pump products. Therefore, the inner ball socket after injection molding must be processed according to the actual value measured by the plunger ball head, which brings great difficulties to mass production.

[0009] During the subsequent rotational closing or extrusion closing process, the carbon fiber reinforced PEEK engineering plastic injected into the ball socket inside the sliding shoe is prone to cracking, the metal matrix peeling off, and the different closing gaps in batches lead to inconsistent performance of subsequent batch products, which seriously affect product performance and mass production.

[0010] The control accuracy of the closing position is poor, the concentricity of the plunger ball head and the ball socket in the sliding shoe is poor, and the distance D from the bottom end surface of the sliding shoe to the center of the plunger ball is difficult to control accurately. In long-life pump applications, subsequent wear is large, the pump noise is high, and the engineering plastic in the ball socket in the sliding shoe is prone to breakage, resulting in sudden failure of the pump.

[0011] Attached Figure 5 Method 2 is an improvement on Method 1. Figure 5 It can be seen that the solution is to first manufacture and process the metal shoe base, process the outer circle of the plunger and the ball head, integrally inject the shoe base and the plunger, and process the outer side of the injected shoe. A plunger shoe assembly injection molding method and an injection molding mold disclosed in CN113146937A are the above method. This method mainly uses two half-molds to clamp the plunger and the shoe base and then inject it. The gap between the plunger and the shoe is controlled by the shrinkage rate of the material to solve the problem of mass production. The post-processing process is relatively simple, and the size control of the plunger ball head does not need to be particularly precise, which reduces the production cost. This method has become one of the commonly used methods for manufacturing water hydraulic pump shoe plunger complexes. In actual applications, it is found that this method has the following prominent disadvantages: The plunger ball head is directly placed in the ball socket inside the metal matrix of the sliding shoe. Therefore, the diameter of the upper plunger ball head must be smaller than the radial dimension of the entrance of the inner ball socket. As a result, after the injection molding is completed, when the plunger ball head is pulled, the ball socket pressure mainly acts on the carbon fiber reinforced PEEK engineering plastic. Because the strength of the engineering plastic itself is much smaller than the strength of the metal, the thin layer of fiber reinforced PEEK engineering plastic injected in the ball socket is easily pulled off. This phenomenon is more obvious in high pressure, large flow and heavy load occasions. Figure 3 The failure phenomenon of the slipper being pulled off in actual engineering is the slipper-plunger complex produced by the same process method.

[0012] In the manufacturing process described in the second method, the process hole on the top of the sliding shoe is not injection molded. In the subsequent processing, the sliding shoe plunger is a movable fit, which can easily lead to the drill bit breaking during the processing and resulting in processing scrap.

[0013] During the injection molding process, the relative positions of the two half-molds clamping the plunger and the sliding shoe base cannot be accurately controlled, so the distance D from the bottom end surface of the sliding shoe to the center of the plunger ball is difficult to accurately control, resulting in prominent phenomena such as loud vibration and noise and unstable movement during the subsequent operation of the pump.

[0014] During the injection molding process described in the second method, the fiber-reinforced PEEK engineering plastic has poor thermal fluidity. After the workpiece plunger meets the plunger spherical surface after injection molding, the temperature drops rapidly, resulting in a more serious phenomenon of "incomplete filling". Summary of the invention

[0015] In order to solve the difficulties in the current processing, manufacturing and application of the slipper-plunger complex of the water hydraulic axial piston pump and achieve further breakthroughs in water hydraulic technology, the present invention provides an integrated injection mold for a slipper-plunger with an automatic closing function of a slipper base and an injection molding method.

[0016] Attached Figure 6 is a three-dimensional side perspective view of the injection mold of the present invention in a compacted state, Figure 7 is a three-dimensional side perspective view of the injection mold of the present invention in a semi-compacted state, Figure 8 It is a front cross-sectional view of the injection mold of the present invention, as shown in the attached Figure 6 , Attachment Figure 7 And attached Figure 8 As shown, the injection mold of the present invention includes an upper mold pad, an upper mold top plate, a glue injection port, a gate sleeve, an upper mold plate, an upper mold inclined slider, a lower mold inclined guide block, an inner mold inclined slider, a lower mold inclined guide pin, an inner mold closing shape clamp, an inner mold core lower body, a lower mold supporting plate, an ejector pin, a lower mold spacer plate, an upper ejector pin plate, a lower mold bottom plate, a lower mold pad, a lower mold guide pin, a lower mold guide pin spring, an upper mold guide pin, an upper mold guide pin copper sleeve and hexagon socket screws for fixed connection and general injection mold parts such as pins.

[0017] Similar to conventional injection molds, the upper mold pad and the injection port are fixedly installed on the upper top surface of the upper mold top plate by hexagon socket screws, the center of the injection port coincides with the center hole of the upper mold top plate, the gate sleeve is installed in the center hole of the upper mold top plate and the center hole of the upper mold plate, the upper end surface of the gate sleeve is against the lower bottom surface of the injection port, the lower end surface of the upper large diameter of the gate sleeve is against the upper surface of the upper large diameter center hole of the upper mold top plate, the upper mold top plate and the upper mold plate are fixedly connected by hexagon socket screws uniformly distributed along the circumferential direction, the upper mold inclined slider is a centrally slotted inclined structure, the inclination angle is the same set value as the inner mold inclined slider, the lower mold inclined guide block and the lower mold plate inclined guide column mounting hole, the top surface of the upper mold inclined slider and the lower groove of the upper mold plate The grooves are abutted against each other and are fixedly connected by hexagon socket screw mounting countersunk holes evenly distributed on the top of the upper template and the threaded holes on the top of the upper mold inclined sliding block; a conical central flow channel hole for glue injection is arranged in the center of the inner mold core upper cover; the top surface of the inner mold core upper cover and the grooves below the upper template are abutted against each other and are fixedly connected by hexagon socket screw mounting countersunk holes evenly distributed on the top of the upper template and the threaded holes on the top of the inner mold core upper cover; the bottom surface of the inner mold core upper cover is provided with grooves that conform to the injection shape and annularly arranged intermittent protrusions that are used to directly act on the sliding shoe base of the injection molded workpiece; the upper mold guide column copper sleeves are evenly distributed around the corners of the upper template and the upper mold top plate; the above structure constitutes the upper mold structure part of the present invention.

[0018] The bottom surface of the lower die inclined guide block and the groove on the top surface of the lower die plate are butted against each other, and the countersunk holes and the threaded holes at the bottom of the lower die inclined guide block are fixedly connected by hexagon socket screws evenly distributed on the bottom of the lower die plate. The lower die inclined guide column is installed in the inclined hole of the lower die inclined guide block with a clearance fit. The upper end surface of the large circular protrusion at the bottom of the lower die inclined guide column and the large circular lower end surface of the inclined hole of the lower die inclined guide block are butted against each other. The inner die inclined slider passes through the side inclined hole and the lower die inclined guide column and slides along the inclined surface direction in the form of clearance sliding fit with the outermost inclined surface and the inner inclined surface of the lower die inclined guide block. The inner die closing shape is located on the side of the clamping plate The inner surface of the side groove of the inner mold inclined slider is abutted against, and the hexagon socket screw mounting countersunk holes evenly distributed on the top of the inner mold inclined slider and the threaded holes on the top of the inner mold closing shape clamping plate are fixedly connected with hexagon socket screws. The inner mold closing shape clamping plate is installed in the square through holes on the left and right sides of the lower body of the inner mold core with intermittent sliding cooperation and can slide to the left and right sides along the radial direction. The lower body of the inner mold core can slide up and down in the central groove of the lower template in a clearance fit manner. The top center circular hole of the lower body of the inner mold core is provided with an annular hole that cooperates with the injection workpiece sliding shoe base to form the workpiece required for injection molding. Four holes are arranged around the support plate and the lower template to match the lower mold guide column. The upper and lower end surfaces of the upper large circular part of the lower mold guide column are respectively fixedly mounted against the lower mold support plate of the lower template. The top of the ejector pin is a needle-shaped structure with the same shape requirement as the required injection molded workpiece. The large conical end surface of the ejector pin is against the conical surface of the inner hole of the injection molded workpiece plunger. The upper end of the large circular ring surface at the bottom of the ejector pin is against the lower end surface of the annular groove of the upper ejector plate, and the lower end of the large circular ring surface at the bottom of the ejector pin is against the upper end surface of the lower ejector plate. The upper ejector plate is installed with hexagon socket screws evenly distributed around the countersunk holes and the bottom of the lower ejector plate. The threaded holes on the top are fixedly connected by hexagon socket screws, the lower die bottom plate is fixedly connected by hexagon socket screw mounting countersunk holes evenly distributed around and the threaded holes at the bottom of the lower die spacer plate by hexagon socket screws, the lower die pad is mounted on the lower die bottom plate by hexagon socket screw mounting countersunk holes evenly distributed around the periphery, and holes are provided at the center and left and right sides of the lower die bottom plate for a lifting device to push the lower ejector plate upward. The lower die supporting plate connects the lower template, the lower die inclined guide block, the lower die spacer plate and the lower die bottom plate through threaded holes and through holes arranged around and inside to form the lower die structure part of the present invention.

[0019] The inner mold core upper cover and the inner mold core lower body are arranged with flow passages connected end to end, and are connected to the oil inlet and outlet of the mold temperature controller through the oil pipe joints installed on the front and rear sides. Fig. 9 This is a partial enlarged view of the bottom of the inner mold core cover. The discontinuous protrusions that counteract the bottom of the inner mold core cover and the substrate of the injection molded workpiece slide shoe are arranged in a ring, and the protrusion gap area is not greater than the set value of the total area. The effective extension length of the upper mold guide pin is greater than the total length of the workpiece. After the upper mold slides out, the middle size of the upper and lower molds is greater than the workpiece removal length.

[0020] Attached Fig.10This is a front cross-sectional view of the inner mold closing shape clamp. The upper end of the closing shape is a multi-line segment arc structure, and the lower end is a ring-shaped matching shape of the lower end of the spherical surface of the injection molded workpiece plunger. The material is made of high-hardness mold steel and has been hardened by high-temperature heat treatment. There are annular gaps and flow holes on the top and side of the injection molded workpiece sliding shoe base.

[0021] The materials of the lower template inclined guide column and the lower die inclined guide block are soft and hard matching materials, among which the material of the lower template inclined guide column is aluminum bronze with lower hardness, and the lower die inclined guide block is a mold steel material that has been strengthened; the upper end surface of the lower die inclined guide block and the lower template inclined guide column that contacts to form a sealing surface is finely ground.

[0022] The technical effects of the present invention are embodied in: 1. Combining the advantages and disadvantages of existing processing methods, the mold with integrated design of closing and injection molding collects the advantages of existing processing methods, solves many shortcomings of existing sliding shoe plunger complex processing methods, and has a major technical breakthrough for the further development of water hydraulic pump technology.

[0023] 2. It solves the problem of complicated pre-processing and post-processing technology and the lack of mass production in the existing technology, laying a foundation for the mass and automated production of water hydraulic technology.

[0024] 3. Through the shape positioning of the inner mold closing shape clamp, the injection molding is completed as attached Figure 2 The precise control of the distance D from the bottom end surface of the sliding shoe to the center of the plunger ball shown in the figure improves the processing consistency of the sliding shoe-plunger complex and lays the foundation for the subsequent improvement of the comprehensive performance of the pump.

[0025] 4. The integrated ejector pin design simplifies the subsequent processing of the center hole of the sliding shoe and improves the yield rate in the manufacturing process.

[0026] 5. A new design of sliding injection mold is proposed. With the joint action of multiple sliders, molds, guide pillars, and action clamps, the injection mold is pressed down to lock the mold while the metal base of the sliding shoe is closed, thereby improving the anti-pull-off performance of the sliding shoe.

[0027] 6. According to the different workpieces, a process method of heating the mold and workpiece at the same time and post-injection treatment of the workpiece is proposed to improve the injection molding yield.

[0028] Attached Fig.11The invention discloses an injection molding process method, which is specifically as follows: generally processing a metal substrate of a sliding shoe, generally processing an outer circle and a ball head of a plunger, fine grinding an outer circle and a ball head of the plunger, preheating the metal substrate of the sliding shoe and the plunger to a set temperature and keeping the temperature for a set time, heating a mold core in an injection mold to a set temperature, placing the metal substrate of the sliding shoe and the plunger into the injection mold, pressing the upper mold down to a set position to close and lock the mold, injection molding, ejecting the injection-molded sliding shoe-plunger complex to demold, placing the injection-molded sliding shoe-plunger complex into a heating box and keeping the temperature at a set temperature for a set time, and processing the outer end surface to form the sliding shoe-plunger complex. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 Schematic diagram of a typical water hydraulic axial piston pump structure.

[0030] Figure 2 Schematic diagram of the typical all-water-lubricated axial piston pump slipper-piston complex structure.

[0031] Figure 3 Photos of failures caused by the skid shoes being pulled off during actual engineering work.

[0032] Figure 4 A diagram of the existing manufacturing process for a sliding shoe plunger complex that is first processed and then closed.

[0033] Figure 5 A diagram of the existing one-piece injection molding manufacturing process for an unclosed sliding shoe plunger complex.

[0034] Figure 6 A three-dimensional side perspective view of the injection mold of the present invention in a compacted state.

[0035] Figure 7 A three-dimensional side perspective view of the injection mold of the present invention in a semi-pressed state.

[0036] Figure 8 Front cross-sectional view of the injection mold of the present invention.

[0037] Fig. 9 A partial enlarged view of the inner mold core.

[0038] Fig.10 Front cross-sectional view of the inner mold closing shape clamp.

[0039] Fig.11 Diagram of the injection molding manufacturing process of the present invention. DETAILED DESCRIPTION

[0040] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0041] As attached Figure 6 , Attachment Figure 7 And attached Figure 8As shown, the present invention includes an upper mold pad 1, an upper mold top plate 2, a glue injection port 3, a gate sleeve 4, an upper mold plate 5, an upper mold inclined slider 7, a lower mold inclined guide block 9, an inner mold inclined slider 10, a lower mold inclined guide column 11, an inner mold closing shape clamp 12, an inner mold core lower body 13, a lower mold supporting plate 14, an ejector pin 15, a lower mold spacer plate 16, an upper ejector pin plate 17, a lower mold bottom plate 19, a lower mold pad 20, a lower mold bottom plate sleeve 21, a lower mold guide column spring 22, an upper mold guide column 23, an upper mold guide column copper sleeve 24 and hexagon socket screws for fixed connection and other common mold parts such as pins.

[0042] According to the present invention Fig.11 The process method described above generally processes the metal substrate of the sliding shoe first. On the premise of ensuring the shape and position tolerance of the substrate, the surface roughness can be roughly processed to ensure the processing efficiency and the adhesion of the subsequent injection-molded engineering plastics; the outer circle and the ball head of the plunger need to be precisely processed in place, and the size and surface roughness should meet the required standards. In order to ensure the processing efficiency, the size tolerance of the ball head can be appropriately relaxed, but the shape error of the ball head should be guaranteed; the metal substrate of the sliding shoe and the plunger are preheated in an insulation box to a set temperature and kept warm for a set time to complete the preparation work before injection molding.

[0043] The injection mold of the present invention is installed on an injection molding machine, and the mold temperature controller is turned on. After the upper and lower bodies of the inner mold core of the injection mold are heated to a set temperature through the mold temperature controller circulating oil circuit, the sliding shoe metal matrix and the plunger are placed in the injection mold. At this time, the lower body of the inner mold core is located at the upper part of the lower mold plate, and the ejector pin is located at the lower part of the center hole of the workpiece. Under the action of the lower mold inclined guide block, the inner mold inclined slide block, and the lower mold plate inclined guide column, the inner mold closing shape clamps on both sides are in an open position, and the sliding shoe plunger can be installed as a whole in the center hole of the lower body of the inner mold core and can slide freely up and down. After reaching the set injection temperature, the upper mold descends under the downward pressure of the hydraulic cylinder on the injection molding machine. The upper mold is pressed down by the upper mold inclined slider installed on the upper template, and under the action of the lower mold inclined guide block, the inner mold inclined slider and the lower template inclined guide column, the inner mold closing shape clamps on both sides are closed to the center position. At the same time, the lower ejector is against the injection workpiece plunger through the upper conical large end face to limit the plunger from continuing to move downward. The inner mold closing shape clamp continues to move toward the middle until the inner mold closing shape clamp is tightened and stuck in the annular groove at the bottom of the plunger ball head. At the same time, the intermittent protrusion on the inner mold cover that acts on the bottom and the injection workpiece sliding shoe base presses down the sliding shoe metal base and the inner arc surface of the inner mold closing shape clamp interacts with each other to complete the closing process and the clamping process.

[0044] After completing the closing and clamping processes at the same time, the injection molding machine injects PEEK engineering plastics into the inner and outer surfaces and annular grooves of the metal matrix of the sliding shoe at the set temperature. In order to improve the fluidity of the injection molding of PEEK engineering plastics, holes of set aperture sizes are evenly distributed in the axial and radial directions in the metal matrix. After completing the injection molding and pressure holding processes, the upper mold opens under the pulling force of the upper hydraulic cylinder of the injection molding machine. At the same time, the lower hydraulic cylinder of the injection molding machine pushes the upper and lower plates of the ejector to drive the ejector to move up, pushing the inner mold core to move up. Under the action of several inclined sliders and inclined guide pillars, the inner mold closing shape clamp opens, and the ejector ejects the workpiece.

[0045] In the process method, the injection-molded sliding shoe plunger complex is placed in a heating box and kept warm at a set temperature for a set time before the outer end surface can be processed and formed.

[0046] The above embodiments are only to illustrate the basic principles and characteristics of the present invention. The present invention is not limited by the above examples. Without departing from the spirit and scope of the present invention, the present invention may be subject to various changes and modifications, which are within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A one-piece injection mold for a sliding shoe plunger with an automatic closing function for the sliding shoe base, characterized in that The utility model comprises an upper mold pad (1), an upper mold top plate (2), a glue injection port (3), a sprue sleeve (4), an upper mold plate (5), an upper mold inclined slide block (6), an inner mold core upper cover (7), a lower mold plate (8), a lower mold inclined guide block (9), an inner mold inclined slide block (10), a lower mold inclined guide column (11), an inner mold closing shape clamp (12), an inner mold core lower body (13), a lower mold support plate (14), an ejector pin (15), a lower mold spacer plate (16), an upper ejector pin plate (17), a lower ejector pin plate (18), a lower mold bottom plate (19), a lower mold pad (20), a lower mold guide column (21), and a lower mold guide column. The spring (22), the upper die guide pin (23), the upper die guide pin copper sleeve (24) and the hexagon socket screws for fixing the connection, the upper die pad (1) and the glue injection port (3) are fixedly mounted on the upper top surface of the upper die top plate (2) by means of the hexagon socket screws, the center of the glue injection port (3) coincides with the center hole of the upper die top plate (2), the gate sleeve (4) is mounted in the center hole of the upper die top plate (2) and the center hole of the upper mold plate (5), the upper end surface of the gate sleeve (4) abuts against the lower bottom surface of the glue injection port (3), the lower end surface of the upper large diameter of the gate sleeve (4) and the upper large diameter center hole of the upper die top plate (2) coincide with each other. The upper mold top plate (2) and the upper mold plate (5) are fixedly connected by hexagon socket screws evenly distributed along the circumferential direction. The upper mold inclined slider (6) is a centrally slotted inclined surface structure. The inclination angle is the same as the setting value of the inner mold inclined slider (10), the lower mold inclined guide block (9) and the lower mold inclined guide column (11) installation hole. The top surface of the upper mold inclined slider (6) and the lower groove of the upper mold plate (5) are abutted and fixedly connected by hexagon socket screws evenly distributed on the top of the upper mold plate (5) and the threaded hole on the top of the upper mold inclined slider (6). The center of the inner mold core upper cover (7) is provided with a hole for injection molding. The conical center flow channel hole of the glue, the top surface of the inner mold core cover (7) and the groove on the bottom of the upper mold plate (5) are abutted and fixedly connected by hexagon socket screw mounting countersunk holes evenly distributed on the top of the upper mold plate (5) and the threaded holes on the top of the inner mold core cover (7), the bottom surface of the inner mold core cover (7) is provided with grooves corresponding to the injection shape and annularly arranged intermittent protrusions for directly acting on the injection workpiece sliding shoe base (26), the upper mold guide column copper sleeve (24) is evenly distributed along the four sides at the corners of the upper mold plate (5) and the upper mold top plate (2), the above structure constitutes the upper mold structure part of the present invention.

2. A one-piece injection mold for a sliding shoe and a plunger with an automatic closing function for the sliding shoe base, characterized in that: The bottom surface of the lower die inclined guide block (9) and the groove on the top surface of the lower die plate (8) are abutted against each other and the countersunk holes and the threaded holes at the bottom of the lower die inclined guide block (9) are fixedly connected by hexagon socket screws evenly distributed at the bottom of the lower die plate (8). The lower die plate inclined guide column (11) is installed in the inclined hole of the lower die inclined guide block (9) with a clearance fit. The upper end surface of the large circular protrusion at the bottom of the lower die plate inclined guide column (11) and the large circular lower end surface of the inclined hole of the lower die inclined guide block (9) are abutted against each other. The inner die inclined slide block (10) slides along the inclined surface in the form of a clearance sliding fit through the side inclined hole and the lower die plate inclined guide column (11) and through the outermost inclined surface and the inner inclined surface of the lower die inclined guide block (9). The side surface and the inner surface of the inner die closing clamp (12) are connected. The inner surface of the side groove of the mold inclined slider (10) is abutted against each other, and the hexagon socket screw mounting countersunk holes evenly distributed on the top of the inner mold inclined slider (10) and the threaded holes on the top of the inner mold closing shape clamping plate (12) are fixedly connected by hexagon socket screws. The inner mold closing shape clamping plate (12) is installed in the square through holes on the left and right sides of the inner mold core lower body (13) in an intermittent sliding fit and can slide to the left and right sides along the radial direction. The inner mold core lower body (13) can slide up and down in the central groove of the lower mold plate (8) in a clearance fit manner. The top center circular hole of the inner mold core lower body (13) is provided with an annular hole that cooperates with the injection workpiece sliding shoe base (26) to form the workpiece required for injection molding. The lower mold support plate (14) and the lower mold plate (8) are connected to the inner mold core lower body (13) and the inner mold core lower body (13) are connected to the inner mold core lower body (13). ) is provided with four holes around the lower mold guide column (21) to match, the upper and lower end surfaces of the upper large circular part of the lower mold guide column (21) are respectively fixedly mounted against the lower mold plate (8) and the lower mold support plate (14), the top of the ejector pin (15) is a needle-shaped structure with the same shape requirements as the required injection molded workpiece, the large conical end surface of the ejector pin (15) is against the conical surface of the inner hole of the injection molded workpiece plunger (25), the upper end of the large circular ring surface at the bottom of the ejector pin (15) is against the lower end surface of the annular groove of the upper ejector plate (17), the lower end of the large circular ring surface at the bottom of the ejector pin (15) is against the upper end surface of the lower ejector plate (18), the upper ejector plate (17) is installed with countersunk holes and the lower ejector plate (18) through hexagon socket screws evenly distributed around the upper ejector plate (17). ) is fixedly connected with the threaded holes at the bottom by hexagon socket screws, the lower die base plate (19) is fixedly connected with the threaded holes at the bottom of the lower die spacer plate (16) by hexagon socket screws evenly distributed around the lower die base plate (19), the lower die pad (20) is installed on the lower die base plate (19) by hexagon socket screws evenly distributed around the lower die base plate (19), the center and left and right sides of the lower die base plate (19) are provided with holes through which a lifting device for pushing the lower ejector plate (18) to move upward passes, and the lower die support plate (14) is connected to the lower die plate (8), the lower die inclined guide block (9), the lower die spacer plate (16), and the lower die base plate (19) by threaded holes and through holes arranged around and inside to form the lower die structure part of the present invention.

3. A sliding shoe plunger integrated injection mold with a sliding shoe base automatic closing function according to claim 1 or 2, characterized in that: The inner mold core upper cover (7) and the inner mold core lower body (13) are provided with flow passages which are connected end to end and are connected to the oil inlet and outlet of the mold temperature controller via oil pipe joints installed on the front and rear sides.

4. A one-piece injection mold for a sliding shoe plunger with an automatic closing function for a sliding shoe base according to claim 1 or 2, characterized in that: The intermittent protrusions that counteract the inner mold core cover (7) and the injection molded workpiece sliding shoe base (26) are three or four in an annular arrangement, and the protrusion gap area is not greater than a set value of the total area.

5. A one-piece injection mold for a sliding shoe plunger with an automatic closing function for a sliding shoe base according to claim 1 or 2, characterized in that: The effective extension length of the upper die guide pin (23) is greater than the total length of the workpiece, and after the upper die slides out, the middle dimension of the upper and lower dies is greater than the removal length of the workpiece.

6. A sliding shoe plunger integrated injection mold with a sliding shoe base automatic closing function according to claim 1 or 2, characterized in that: The upper end of the inner mold closing shape clamping plate (12) is a multi-line segment spliced ​​arc structure, and the lower end is a ring-shaped matching shape of the lower end of the spherical surface of the injection workpiece plunger (25). The material is made of high-hardness mold steel and has undergone high-temperature hardening heat treatment.

Images