A die for forming eccentric steps of helical gears

Abstract

The present invention relates to the field of gear mold technology, and more specifically, to a mold for forming an eccentric step of a helical gear. The beneficial effect is that eccentric steps of different sizes can be integrally machined on a helical gear. A mold for forming an eccentric step of a helical gear comprises a mold box, a mold is fixedly connected to the mold box, a plurality of inclined screw grooves I are evenly distributed on the inner wall of the mold, a top cover is detachably connected to the mold box, a movable mold is detachably connected to the top cover, the movable mold is located between the top cover and the mold, a mold cavity is formed between the mold box, the mold, the movable mold and the top cover, an ejection mechanism for demolding is provided at the lower end of the mold cavity on the mold box, a core mold is installed on the core of the top cover, the core mold passes through the mold cavity and fits with the ejection mechanism, and two injection ports are symmetrically provided on the top cover relative to the core mold.

Description

Technical Field

[0001] The invention relates to the technical field of gear moulds, in particular to a mould for forming eccentric steps of helical gears. Background Art

[0002] Gears can achieve functions such as changing speed and torque, changing direction of movement, and changing the form of movement by transmitting with other toothed mechanical parts such as another gear, rack, and worm gear. The gear and shaft are integrated, and the small steps on both sides of the gear are mainly for easy assembly and to eliminate stress concentration. When the gear and shaft are integrated, since they are not separate, assembly convenience must be considered. If there are no steps, it is inevitable that the assembly of the housing will conflict with the matching gear during assembly. Secondly, due to the force relationship of the gear, if there are no steps, the diameter of the shaft and the bottom diameter of the gear tooth groove are similar, and the force on the tooth part is basically rigid. At startup, it is easy to cause the tooth part to break. With the steps, since the diameter of the shaft is smaller than the bottom diameter of the gear tooth groove, when the gear is under force, the shaft will twist to a certain extent, so that the force acting on the gear tooth part is dispersed and transmitted to the shaft, thereby avoiding damage to the tooth part.

[0003] Patent No. 202110781700.9 describes a one-time-molded multi-hole eccentric step helical gear and its processing technology. This invention overcomes the shortcomings of existing technologies by forming the gear in one go and improving its product performance and quality through multiple processing techniques. However, this device cannot integrally process eccentric steps of varying diameters on helical gears. Summary of the Invention

[0004] In order to overcome the deficiencies of the prior art, the present invention provides a die for forming an eccentric step of a helical gear, which has the beneficial effect of being able to integrally machine eccentric steps of different sizes on the helical gear.

[0005] The technical solution adopted by the present invention to solve its technical problem is:

[0006] A mold for forming an eccentric step of a helical gear comprises a mold box, a mold mold is fixedly connected to the mold box, a plurality of inclined screw grooves I are evenly distributed on the inner wall of the mold mold, a top cover is detachably connected to the mold box, a movable mold is detachably connected to the top cover, the movable mold is located between the top cover and the mold mold, a mold cavity is formed between the mold box, the mold mold, the movable mold and the top cover, an ejection mechanism for demoulding is provided at the lower end of the mold cavity on the mold box, a core mold is installed on the core of the top cover, the core mold passes through the mold cavity and fits with the ejection mechanism, and two injection ports are symmetrically provided on the top cover relative to the core mold.

[0007] It also includes two side groove frames symmetrically fixedly connected to the two ends of the top cover, both of which are inserted into the mold box, and both of which are provided with screw seats, and the two screw seats and the movable mold are detachably connected by screws; a lead screw is connected between the side groove frame and the screw seat on the same side.

[0008] The utility model also comprises a ruler fixedly connected to the top cover, and indicator plates are fixedly connected to the two screw seats, and the tips of the two indicator plates both point to the ruler.

[0009] The top cover and the core mold are slidably connected, two studs are threadedly connected on the core mold, and the two studs are both rotatably connected to the top cover.

[0010] A plurality of inclined screw grooves II are evenly distributed on the outer wall of the mold. The thread lead angles of the screw grooves II and the screw grooves I are equal, and the screw grooves II and the screw grooves I are correspondingly arranged. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The present invention will be further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0012] Figures 1 to 3 This is a structural diagram of a die for forming an eccentric step of a helical gear;

[0013] Figure 4 Schematic diagram of the cross-sectional structure of the mold;

[0014] Figure 5 It is a schematic diagram of the structure of the top cover, movable mold and core mold;

[0015] Figure 6 It is a structural diagram of the cooperation between the mold box and the mold;

[0016] Figure 7 for Figure 6 Schematic diagram of the cross-sectional structure;

[0017] Figure 8 Schematic diagram of the structure of the mold box;

[0018] Figure 9 Schematic diagram of the structure of the mold;

[0019] Figure 10 Schematic diagram of the structure of the top plate;

[0020] Figure 11 Schematic diagram of the matching structure of the movable mold;

[0021] Figure 12 Schematic diagram of the matching structure of the top cover and the core mold;

[0022] Figure 13 Schematic diagram of the split structure of the top cover and the movable mold;

[0023] Figure 14 It is a structural diagram of a cylindrical rod;

[0024] Figure 15 This is a structural diagram of the indicator board and ruler. DETAILED DESCRIPTION

[0025] like Figures 1 to 7 As shown:

[0026] A mold for forming an eccentric step of a helical gear comprises a mold box 101, a mold 201 is welded inside the mold box 101, a plurality of inclined screw grooves I 305 are evenly distributed on the inner wall of the mold 201, a top cover 202 is detachably connected to the mold box 101, a movable mold 301 is movably connected to the top cover 202, the top cover 202 and the movable mold 301 are sealed and fitted together, the axes of the mold box 101, the top cover 202 and the mold 201 coincide, the movable mold 301 is eccentrically arranged between the top cover 202 and the mold 201, the movable mold 301 and the mold 201 are sealed and fitted together, the mold box 101, the mold 201, A mold cavity is formed between the movable mold 301 and the top cover 202. The mold cavity consists of an eccentric step cavity and a helical gear cavity. An eccentric step cavity is formed between the top cover 202 and the movable mold 301. A helical gear cavity is formed between the mold 201 and the mold box 101. An ejection mechanism for demoulding is provided at the lower end of the helical gear cavity on the mold box 101. A core mold 205 is sealed and installed on the core of the top cover 202. The axis of the arc-shaped part of the core mold 205 coincides with the axis of the top cover 202. The core mold 205 passes through the mold cavity and is sealed and fitted with the ejection mechanism. Two injection ports 204 are symmetrically provided on the top cover 202 relative to the core mold 205.

[0027] The raw material for forming the helical gear is injected into the mold cavity through the two injection ports 204, and the raw material is injected into the helical gear cavity between the mold 201 and the core mold 205. Due to the presence of multiple screw grooves I 305, the raw material in the helical gear cavity is directly formed to obtain the helical gear. Due to the setting of the core mold 205, the machined helical gear core has a mounting hole. Since the core mold 205 is provided with ridges, the mounting hole machined on the helical gear has a keyway; the raw material is injected into the eccentric step cavity between the movable mold 301 and the core mold 205, forming a step with a mounting hole and a keyway on the helical gear. Since the movable mold 301 is eccentrically arranged between the top cover 202 and the mold 201, the axis of the movable mold 301 does not coincide with the axis of the core mold 205, and there is a certain distance, which makes the step eccentric relative to the helical gear. Finally, the helical gear with an eccentric step is formed in one piece.

[0028] Secondly, an annular cavity is formed between the mold 201 and the mold box 101. Cooling water is injected into the annular cavity to cool the helical gear and promote its molding. The core mold 205 is hollow, which is also convenient for heat dissipation of the gear core. Cold water can also be injected into the core mold 205 to further promote heat dissipation of the gear core.

[0029] Since the top cover 202 is detachably connected to the mold box 101, after the top cover 202 is removed, the top cover 202 drives the movable mold 301 and the core mold 205 to be removed synchronously, and the formed eccentric step bevel gear is exposed. The eccentric step bevel gear is ejected from the mold cavity by controlling the ejection mechanism to achieve demoulding;

[0030] Since the movable mold 301 and the top cover 202 are detachably connected, the movable mold 301 with different inner diameters can be replaced, and eccentric steps with different diameters can be integrally machined on the helical gear.

[0031] like Figures 11 to 13 As shown:

[0032] A mold for forming an eccentric step of a helical gear, further comprising two side groove frames 203 symmetrically fixedly connected to both ends of a top cover 202, both side groove frames 203 being inserted into a mold box 101, the side groove frames 203 and the mold box 101 being detachably connected by screws, both side groove frames 203 being inserted with screw seats 302, the two screw seats 302 and the movable mold 301 being detachably connected by screws; a lead screw 303 being connected between the side groove frame 203 and the screw seat 302 on the same side, one end of the lead screw 303 being rotatably connected to the screw seat 302, and the other end of the lead screw 303 being threadedly connected to the side groove frame 203;

[0033] The movable mold 301 is provided with two threaded holes, and the screws on the two screw seats 302 are respectively threadedly connected to the two threaded holes on the movable mold 301 to achieve the installation and fixation of the movable mold 301; because the screw seats 302 can slide on the side groove frame 203, the two lead screws 303 are rotated at the same time, so that the two screw seats 302 move synchronously to the left or right, thereby changing the position of the movable mold 301 relative to the top cover 202, that is, changing the distance between the axes of the top cover 202 and the movable mold 301, thereby changing the eccentricity of the eccentric step, and processing the eccentric steps of the helical gears with different eccentricities, so that the helical gears are suitable for different stress environments; when changing the eccentricity of the movable mold 301, it is necessary to ensure that the top cover 202 always covers the inner ring of the movable mold 301, and the inner ring of the movable mold 301 does not exceed the outer ring of the mold 201, thereby preventing the raw material from leaking from the mold cavity;

[0034] After the movable mold 301 is removed, by changing the distance between the two screw seats 302, movable molds 301 of different sizes or movable molds 301 of different inner diameters can be installed, and eccentric steps of different diameters can be integrally machined on the helical gear.

[0035] After loosening the screws between the side groove frame 203 and the mold box 101, the top cover 202 can be removed, which makes it easy to replace the movable mold 301 of different sizes or to eject the bevel gear.

[0036] like Figures 11 to 13 and Figure 15 As shown:

[0037] A mold for forming an eccentric step of a helical gear, further comprising a scale 207 bonded to a top cover 202, two screw seats 302 each having an indicator plate 304 fixedly connected thereto by screws, the tips of the two indicator plates 304 both pointing to the scale 207;

[0038] When the position of the two screw seats 302 relative to the top cover 202 is changed by rotating the screw 303, the position between the indicator plate 304 and the scale 207 is also changed. Then, the distance between the movable mold 301 and the core mold 205 can be estimated by pointing the indicator plate 304 to the scale value on the scale 207, thereby determining the eccentricity between the machined eccentric step and the helical gear.

[0039] like Figures 11 to 12 As shown:

[0040] The top cover 202 and the core mold 205 are sealed and slidably connected, and two studs 206 are threadedly connected to the core mold 205, and the two studs 206 are rotatably connected to the top cover 202;

[0041] When the two studs 206 are rotated, the position of the core mold 205 relative to the top cover 202 can be changed, thereby changing the length of the core mold 205 at the lower end of the top cover 202. When the two side groove frames 203 on the top cover 202 are installed on the mold box 101 and fixed by screws, the bottom surface of the core mold 205 is still sealed and fitted with the ejection mechanism, thereby changing the distance between the top cover 202 and the bottom surface of the mold box 101. Since the height of the mold 201 is fixed, the overall height of the processed eccentric step can be changed while the height of the molded eccentric gear remains unchanged, thereby adapting to different usage scenarios.

[0042] like Figure 9 As shown:

[0043] A plurality of inclined screw grooves II 306 are evenly distributed on the outer wall of the mold 201. The screw grooves II 306 and the screw grooves I 305 have the same thread lead angle, and the screw grooves II 306 and the screw grooves I 305 are arranged correspondingly.

[0044] The multiple screw grooves I 305 on the inner ring of the mold 201 and the multiple screw grooves II 306 on the outer ring are distributed in the same shape, angle and direction, so that the screw grooves I 305, whether at the root or the tip of the tooth, are all in contact with the cold water in the mold box 101. The thickness of the mold 201 is equal, so that after the helical gear is formed, the tip and root of the tooth can dissipate heat evenly, so that the strength of the tooth part of the helical gear after forming is consistent.

[0045] like Figures 6 to 10 As shown:

[0046] The ejection mechanism includes a top plate 103. The bottom surface of the mold box 101 is provided with a receiving groove 102 for accommodating the top plate 103. The lower end of the top plate 103 is fixedly connected to the shaft rod 104. The shaft rod 104 is sealed and rotatably connected to the mold box 101. The bottom surface of the core mold 205 is attached to the top plate 103.

[0047] The top plate 103 located inside the receiving groove 102 is coplanar with the bottom surface of the mold box 101. When the top cover 202 is opened, the shaft 104 drives the top plate 103 to move upward. The top plate 103 moves upward and drives the formed helical gear to move upward and rotate clockwise along the inclined direction of the screw groove Ⅰ305, thereby realizing the demolding of the helical gear and the mold 201.

[0048] like Figure 8 and Figure 10 As shown:

[0049] A plurality of screw threads 308 are evenly distributed on the circumferential surface of the top plate 103. The screw threads 308 have the same lead angle as the screw grooves I 305. A plurality of screw grooves III 307 matching the screw threads 308 are evenly distributed on the circumferential surface of the receiving groove 102. The screw grooves III 307 are connected to the core mold 205.

[0050] The screw thread 308 corresponds to the gear tooth portion on the helical gear, so that when the top plate 103 rotates upward to drive the helical gear to be demolded, the top plate 103 can contact the entire bottom surface of the helical gear, and the contact area is large, so that the helical gear is subjected to more uniform force during the demolding process, thereby avoiding deformation of the helical gear during the demolding process; the shaft 104 drives the top plate 103 to move upward while rotating clockwise, so that the screw thread 308 on the top plate 103 rotates upward and enters the screw thread groove I 305, and then the screw thread 308 rotates upward along the path of the screw thread groove I 305. During this process, the screw thread 308 always maintains contact with the gear teeth on the helical gear, and also provides support and support for the gear tooth portion, and then pushes the helical gear to rotate upward along the path of the screw thread groove I 305 to be demolded.

[0051] like Figure 7 and Figure 14 As shown:

[0052] The lower end of the shaft 104 is fixedly connected to the groove wheel 105, which is inserted into the edge frame 106. The two ends of the two edge frames 106 are slidably connected to a side frame 107, and the two side frames 107 are fixedly connected to the mold box 101; an electric push rod is fixedly connected between the mold box 101 and the edge frame 106, and the telescopic rod of the electric push rod is fixedly connected to the edge frame 106; two arc-shaped plates are symmetrically fixedly connected inside the edge frame 106, and both arc-shaped plates are inserted into the groove wheel 105 to limit the groove wheel 105 so that the groove wheel 105 can only rotate;

[0053] The electric push rod starts to drive the edge frame 106 to move upward, and the edge frame 106 drives the shaft rod 104 and the top plate 103 to move upward to demould the helical gear through cooperation with the groove wheel 105, without affecting the rotation of the groove wheel 105 and the shaft rod 104.

[0054] like Figure 10 and Figure 14 As shown:

[0055] The shaft 104 is provided with a spiral groove 109, and a cylindrical rod 108 is inserted at the upper end of the spiral groove 109, and the cylindrical rod 108 is fixedly connected to a side frame 107; when the shaft 104 moves upward, the cylindrical rod 108 slides in the spiral groove 109, thereby driving the shaft 104 to rotate, so that the shaft 104 rotates and moves upward, realizing the rotational upward demoulding of the helical gear, and the demoulding process is stable.

[0056] Further:

[0057] The thread lead angles of the spiral groove 109 and the screw groove I 305 are equal; therefore, when the spiral groove 109 on the shaft 104 passes through the cylindrical rod 108, the cylindrical rod 108 can drive the shaft 104 to rotate, and at the same time, the rotation angle and the rising height of the shaft 104 are equal to the rotation angle and the rising height of the screw 308 in the screw groove I 305, thereby achieving the screw 308 on the top plate 103 being able to rotate upward to drive the helical gear to demold.

Claims

1. A die for forming an eccentric step of a helical gear, characterized by: The invention comprises a mold box (101), wherein a mold (201) is fixedly connected to the mold box (101), a plurality of inclined screw grooves I (305) are evenly distributed on the inner wall of the mold (201), a top cover (202) is detachably connected to the mold box (101), a movable mold (301) is detachably connected to the top cover (202), the movable mold (301) is located between the top cover (202) and the mold (201), a mold cavity is formed between the mold box (101), the mold (201), the movable mold (301) and the top cover (202), an ejection mechanism for demoulding is provided at the lower end of the mold cavity on the mold box (101), a core mold (205) is installed on the core of the top cover (202), the core mold (205) passes through the mold cavity and is fitted with the ejection mechanism, and two injection ports (204) are symmetrically provided on the top cover (202) relative to the core mold (205); It also includes two side groove frames (203) symmetrically fixedly connected to both ends of the top cover (202), the two side groove frames (203) are both inserted into the mold box (101), and the two side groove frames (203) are both inserted with screw seats (302), and the two screw seats (302) and the movable mold (301) are detachably connected by screws; a lead screw (303) is connected between the side groove frame (203) and the screw seat (302) on the same side; It also includes a ruler (207) fixedly connected to the top cover (202), and indicator plates (304) fixedly connected to the two screw seats (302), with the tips of the two indicator plates (304) pointing to the ruler (207).

2. The mold for forming the eccentric step of a helical gear according to claim 1, characterized in that: The top cover (202) and the core mold (205) are slidably connected, and two studs (206) are threadedly connected to the core mold (205), and the two studs (206) are both rotatably connected to the top cover (202).

3. The mold for forming the eccentric step of a helical gear according to claim 1, characterized in that: A plurality of inclined screw grooves II (306) are evenly distributed on the outer wall of the mold (201), the screw grooves II (306) and the screw grooves I (305) have the same thread lead angle, and the screw grooves II (306) and the screw grooves I (305) are arranged correspondingly.

4. The mold for forming the eccentric step of a helical gear according to claim 2, characterized in that: The ejection mechanism includes a top plate (103), a bottom surface of the mold box (101) is provided with a receiving groove (102) for accommodating the top plate (103), a lower end of the top plate (103) is fixedly connected to a shaft rod (104), and the shaft rod (104) is sealed and rotatably connected to the mold box (101), and the bottom surface of the core mold (205) is attached to the top plate (103).

5. The mold for forming the eccentric step of a helical gear according to claim 4, characterized in that: A plurality of screw threads (308) are evenly distributed on the circumferential surface of the top plate (103), and the screw threads (308) have the same thread lead angle as the screw thread grooves I (305). A plurality of screw thread grooves III (307) matching the screw threads (308) are evenly distributed on the circumferential surface of the receiving groove (102).

6. The mold for forming the eccentric step of a helical gear according to claim 4, characterized in that: The lower end of the shaft (104) is fixedly connected to a groove wheel (105), and the groove wheel (105) is inserted into the edge frame (106). Both ends of the two edge frames (106) are slidably connected to a side frame (107), and the two side frames (107) are fixedly connected to the mold box (101).

7. The mold for forming the eccentric step of a helical gear according to claim 6, characterized in that: The shaft rod (104) is provided with a spiral groove (109), the upper end of the spiral groove (109) is inserted with a cylindrical rod (108), and the cylindrical rod (108) is fixedly connected to a side frame (107).

8. The die for forming the eccentric step of a helical gear according to claim 7, characterized in that: The thread lead angles of the spiral groove (109) and the thread groove I (305) are equal.

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