A saddle forming process

Abstract

The application relates to the technical field of saddle forming, in particular to a saddle forming process, which comprises the following steps: S1, a leather pre-forming stage; S11, laying release paper in a cavity of a pre-forming die and filling material for forming a saddle leather; S12, scraping off the excess material to ensure that the material completely fills a cavity groove of the pre-forming die; S13, heating or standing at room temperature to semi-solidify the leather; S2, a transferring and foaming stage: S21, transferring the semi-solidified leather to a lower die of a saddle foaming forming die and positioning and compressing; S22, vacuumizing, so that the leather enters a model cavity downwards and is attached to a lower die surface; S23, filling foaming material and then closing the die; and S24, opening the die to take out the formed saddle.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of saddle forming, in particular to a saddle forming process. BACKGROUND

[0002] The saddle is an important part of the bicycle, and the quality of the saddle affects the experience of the rider during the riding process.

[0003] The saddle includes a base, the base is covered with an outer leather cover, and there is a foamed material with elasticity between the base and the outer leather cover. During forming, the outer leather cover is placed in the saddle forming mold, and then after the processes of vacuumizing, injection molding, and mold closing, the saddle can be formed.

[0004] During the vacuumizing process, the outer leather cover will be stretched, and if the surface is damaged during subsequent use, the damage range will continue to expand due to the elasticity of the outer leather cover itself, ultimately leading to a shortened service life of the saddle and making it unable to continue to be used. SUMMARY

[0005] The present application provides a saddle forming process to solve the problems in the background art.

[0006] The above technical purpose of the present application is achieved through the following technical scheme:

[0007] A saddle forming process, comprising the following steps:

[0008] S1, leather pre-forming stage:

[0009] S11: lay release paper in the cavity of the pre-forming mold, and fill the material for forming the saddle leather;

[0010] S12: remove excess material to ensure that the material completely fills the cavity groove of the pre-forming mold;

[0011] S13: stand still to semi-solidify the leather;

[0012] S2, transfer and foaming stage:

[0013] S21: transfer the semi-solidified leather to the lower mold of the saddle foaming forming mold and position and press tightly;

[0014] S22: vacuumize, the leather enters the model cavity downward and adheres to the lower mold surface;

[0015] S23: mold after filling the foaming material;

[0016] S24: open the mold and take down the formed saddle.

[0017] By adopting the above scheme, in the preforming stage, the leather substrate is first filled into the preforming mold cavity, and when the leather substrate is in a semi-cured state, the material has moderate fluidity, can uniformly fill the groove and retain certain plasticity; after being transferred to the foaming mold, vacuum is extracted to make the semi-cured leather complete the final curing while completely adhering to the lower mold surface, avoiding problems such as local debonding, wrinkling or cracking caused by the difference in thermal expansion coefficient when the fully cured leather is directly foamed, and the subsequent foaming filling and mold closing are carried out under the condition that the leather has been stably set, so that the foaming material and the leather layer are more closely combined.

[0018] Further, the step S13 is specifically standing at room temperature, and the standing time is 3-15 minutes.

[0019] Further, in the step S13, standing is carried out while heating, and the heating temperature is 40-65 degrees Celsius.

[0020] Further, the heating time in the step S13 is 3-6 minutes.

[0021] Further, in the step S1, after the doctoring, the filling completeness of the cavity groove of the preforming mold filled with the leather substrate needs to be checked, and if it is not filled, the remaining material scraped off is filled into the groove to completely fill it.

[0022] Further, in the step S2, the lower mold of the saddle foaming forming mold includes a bearing part and a turnover part located above the bearing part, the turnover part is hinged to the bearing part, and the height of the position with the maximum cavity width of the lower mold is equal to or greater than the thickness of the whole bearing part.

[0023] In summary, the present application has the following technical effects:

[0024] 1. By setting the process, in the preforming stage, the leather substrate is first filled into the preforming mold cavity and heated to a semi-cured state, at which time the material has moderate fluidity, can uniformly fill the groove and retain certain plasticity; after being transferred to the foaming mold, vacuum is extracted to make the semi-cured leather complete the final curing while completely adhering to the lower mold surface, avoiding problems such as local debonding, wrinkling or cracking caused by the difference in thermal expansion coefficient when the fully cured leather is directly foamed, and the subsequent foaming filling and mold closing are carried out under the condition that the leather has been stably set, so that the foaming material and the leather layer are more closely combined, reducing defects such as bubbles and material shortages, compared with the traditional process, the leather is directly placed in the foaming mold in a cured state, this phased curing method significantly reduces the problems caused by the thermal stress deformation of the leather, achieves the effect of reducing the scrap rate, and reduces the heating time of the leather in the preforming stage, achieves the effect of improving the efficiency of producing saddles, and overcomes the problems pointed out in the background art.

[0025] 2. By setting the process, in step S1, the filling completeness of the preformed mold cavity groove is checked after scraping, and the unfilled area is supplemented by scraping the excess material, which can significantly improve the uniformity and structural stability of the saddle leather layer;

[0026] 3. By setting the process, the heating temperature is accurately controlled at 40-65 degrees Celsius, and the leather substrate is semi-cured in the preforming stage through mild heating. This process design not only avoids the risk of leather fiber shrinkage, hardening or surface cracking caused by high temperature, but also promotes the moderate crosslinking of substrate molecules through sufficient heat penetration, forming a transition state structure with certain plasticity but not completely shaped, so that it can be more closely fitted to complex curved surfaces through vacuum extraction when transferred to the foaming mold, while leaving room for complete curing reaction for secondary heating, ultimately improving the interfacial bonding strength between the leather layer and the foaming layer, reducing defects such as delamination and bubbles, and maintaining the flexibility and durability of the leather. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 is a process flow chart of an environmentally friendly and energy-saving saddle forming step of the present application;

[0028] Figure 2 is a process flow chart of the leather preforming stage of step S1 of the present application;

[0029] Figure 3 is a process flow chart of the transfer and foaming stage of step S2 of the present application;

[0030] Figure 4 is a structural schematic diagram of the saddle foaming forming mold of the present application.

[0031] In the figure, 1, lower mold; 11, bearing part; 12, turning part. DETAILED DESCRIPTION

[0032] The present application will be further described in detail below with reference to the accompanying drawings.

[0033] Referring to Figures 1-4 The saddle forming process provided by the present embodiment includes a leather preforming stage and a transfer and foaming stage, and the specific operation steps are as follows:

[0034] S1, leather preforming stage:

[0035] S11: Laying release paper in the cavity of the preforming mold and filling the material for forming the saddle leather

[0036] S12: Scraping excess material to ensure that the material completely fills the cavity groove of the preforming mold;

[0037] S13: Heating and standing or standing at room temperature to semi-cure the leather.

[0038] The above steps are to preliminarily shape the leather material through accurate pre-forming mold cavity filling and controlled thermal curing process. Specifically, step S11, laying release paper in the pre-forming mold cavity, which mainly prevents the material from adhering to the pre-forming mold cavity and ensures that the semi-finished product is intact during subsequent demolding; step S12, filling the material and removing the excess part, which forces the material to fully fill the pre-forming mold cavity, eliminates bubbles and voids, and ensures that the leather profile in the semi-cured state is clear and the thickness is uniform; step S13, heating and standing, which activates the crosslinking agent or resin in the material through heat to initiate partial crosslinking reaction of molecular chains, realizes the semi-cured state, so that the material has certain mechanical strength to maintain the shape, and at the same time retains moderate plasticity for subsequent continuous processing. The leather in the semi-cured state with stable structure and accurate size laid in this stage lays a foundation for the subsequent steps and avoids the problem of internal stress concentration or cracking during later processing caused by direct complete curing of the leather.

[0039] S2, transfer and foaming stage:

[0040] S21: transferring the semi-cured leather to the lower mold 1 of the saddle foaming forming mold, positioning and pressing;

[0041] S22: vacuumizing, the leather enters the model cavity downward and is attached to the lower mold 1 profile;

[0042] S23: filling the foaming material and closing the mold;

[0043] S24: opening the mold and taking out the formed saddle.

[0044] It should be noted that in step S2, the semi-cured leather is tightly attached to the lower mold 1 cavity by vacuum negative pressure, which eliminates bubbles and wrinkles and ensures that the leather is attached to the mold with zero gap; then in step S23, the foaming material is filled and the mold is closed, which makes the foaming material decompose and generate gas under heat in the mold, forming a uniform closed-cell foam structure, and at the same time the saddle leather is completely cured by heating.

[0045] In this embodiment, the heating temperature in step S13 is 60-65 degrees Celsius and the standing time is 3-6 minutes.

[0046] In this embodiment, in step S1, the filling completeness of the pre-forming mold cavity groove needs to be checked after the doctor blade coating, and if it is not filled, the excess material is used to fill the groove completely.

[0047] In this embodiment, in step S2, the lower mold 1 of the saddle foaming forming mold includes a bearing part 11 and a turnover part 12 located above the bearing part 11, the turnover part 12 is hinged to the bearing part 11, and the height of the position with the maximum cavity width of the lower mold 1 is equal to or greater than the thickness of the whole bearing part 11.

[0048] The embodiments are only illustrative of the present application, and are not intended to limit the present application, and those skilled in the art can make modifications to the embodiments without creative contribution after reading the specification, but as long as the modifications are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A saddle forming process, characterized in that, Includes the following steps: S1, Leather Pre-forming Stage: S11: Lay release paper flat in the cavity of the pre-forming mold and fill it with the material for forming the saddle leather; S12: Scrape off excess material to ensure that the material completely fills the cavity groove of the preform mold; S13: Let stand while heating at a temperature of 40-65 degrees Celsius for 3-6 minutes to semi-cure the leather; S2, Transfer and Foaming Stage: S21: Transfer the semi-cured leather to the lower mold of the saddle foam molding mold, and position and press it; S22: Vacuum is drawn, and the leather enters the model cavity downwards and fits the lower model surface; S23: After filling with foaming material, close the mold; S24: Open the mold and remove the formed saddle.

2. The saddle forming process according to claim 1, characterized in that: In step S1, after scraping, it is necessary to check the integrity of the cavity groove of the preform mold. If it is not filled, use the scraped-off material to fill until the groove is completely filled.

3. The saddle forming process according to claim 1, characterized in that: In step S2, the lower mold (1) of the saddle foam molding mold includes a supporting part (11) and a flipping part (12) located above the supporting part (11). The flipping part (12) is hinged to the supporting part (11). The height of the position where the cavity width of the lower mold (1) is the largest is equal to or greater than the overall thickness of the supporting part (11).

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