In order to make it easy to understand the technical means, creative features, objectives and effects achieved by the present invention, the present invention will be further explained below in conjunction with specific drawings.
 The leather carving background processing method includes the following steps:
 First, place the leather sculpture background forming mold in a vacuum-sealable cavity. The cavity adopts a regular external shape, such as a square cross-section and longitudinal section. The leather sculpture background forming mold has a work for forming. The working surface can have any external shape. Usually the working surface has an uneven surface. The concave and convex parts of the working surface are consistent with the required product surface form. The background of the leather carving mold and the side of the cavity Close contact and there is a molding space between the working surface and the top of the cavity.
 Second, start the heating system in the cavity enclosure structure at a constant temperature of 50±5°C, preferably 50°C. The heating system has a flow channel provided in the cavity enclosure structure and a thermal fluid that can flow along the flow channel. The hot fluid is provided by an external heating system, the fluid can be water or oil, and the flow channel can be arranged in a serpentine arrangement.
 Third, lay the leather on the working surface of the leather carving background forming mold. The area of the leather is slightly larger than the projected area of the working surface. The decorative surface of the leather faces the working surface and the whole leather is fixed to the cavity of the cavity by the leather fixing frame arranged in the circumferential direction. The upper surface of the side, the lower surface of the leather and the upper surface of the cavity side are in close contact and form a sealed structure under the action of the leather fixing frame. Under the action of the vacuum pump, the leather is pressed on the cavity side by the leather fixing frame The upper surface of the leather part and the lower space of the leather, that is, the part of the cavity where the leather carving background forming mold is installed, can be evacuated. The projected area of the leather is larger than that of the cavity, so the peripheral edge of the leather can be used to form a sealing ring structure. Since the side of the cavity is composed of the front side wall, the rear side wall, the left side wall and the right side wall, the leather fixing frame can be pressed on the side part. Therefore, during the vacuuming process, the leather fixing frame plays a role Prevent leather shrinkage. The lower surface of the leather can have an effective sealing effect due to the particularity of its material.
 Fourth, lock the leather fixing frame and evacuate the cavity so that the leather fits closely with the working surface. There are more vacuum equipment, such as vacuum pumps.
 Fifth, the polyurethane mixture is injected into the molding space where the leather is laid, and then the bottom skin is laid on the surface of the polyurethane mixture. So far, the molding space is distributed with leather, polyurethane mixture and bottom skin from bottom to top.
 Fifth, close the cavity and use the heating system to continuously heat the cavity to make the polyurethane mixture foam and form.
 Finally, after the polyurethane mixture is foamed for 6±2 minutes, the vacuum system is closed, the cavity is opened, the product is taken out, and the remaining material around the product is cut to obtain the finished product.
 The aforementioned processing method uses the vacuum principle to closely adhere the leather to the working surface, which is not easy to produce hollow drums, etc., and the product quality can be guaranteed.
 See Figure 1-3 , A machine used for background processing of leather sculptures, which has: a cavity K surrounded by a lower template 1, an openable upper template 2 and a side 3 arranged between the upper and lower templates, The upper and lower surfaces of the side parts have sealing structures with the upper and lower templates respectively. The cavity here is a square columnar structure. Similarly, the leather carving background molding mold adopts a structure consistent with the shape of the cavity, and the projection area of the leather carving background molding mold is roughly the same as the projection area of the cavity, and the leather carving background molding The periphery of the mold and the side wall of the cavity can be taken and placed freely, and no large gap should be generated. Otherwise, the leather at the edge of the cavity will deform to the bottom of the cavity during the vacuuming process.
 See Figure 2-3 The lower template has a vacuum hole 4 connected with a vacuum system, and the vacuum system has a vacuum pump structure.
 See Figure 2-3 The lower template has a jacking device that can push the leather carving background forming mold out of the cavity. The jacking device has a top block 5 and a screw 6 arranged on the lower template. The top of the screw is connected to the top block. A sealing ring 7 is arranged between the concave part of the top block and the top block of the template installation. The jacking device is arranged in the lower template in a centered manner. This structural design is beneficial for jacking the leather carving background forming mold.
 The lower template is provided with a curved flow channel (not shown in the figure), and the flow channel is connected to the heating system for supplying hot fluid. The flow channel can be arranged in a serpentine manner, and the curved flow channel is convenient for heating. The fluid conducts sufficient heat exchange with the lower template. In view of the need for heat exchange, the lower template can be made of metal materials, such as iron, aluminum and other materials.
 See figure 2 , A locking mechanism is provided between the upper template and the lower template. The locking mechanism includes: a lock module 10 arranged at the non-hinging end of the upper template; a lock buckle (not shown in the figure) located on the side and matched with the lock module.
 See Figure 1-3 , The upper surface of the side part has a leather fixing frame 8 circumferentially arranged on the periphery of the cavity. The leather fixing frame has a circumference larger than the upper template and is hinged to the upper surface of the side part. A sealing ring 9 is provided between the upper surfaces.
 The upper surface of the upper template has a number of regularly or irregularly arranged concave structures, such as staggered concave structures arranged on the upper surface of the upper template, which is more conducive to the exhaust operation during the vacuuming process.
 Among them, the openable upper template and the side are connected by a hinge device, and a bearing 11 is sleeved between the hinge seat and the hinge rod of the hinge device. The hinge device has two adjustments arranged at one end of the upper template. The block W and the hinge seat matched with the adjusting block, the hinge shaft is arranged in the hinge seat and the adjusting block, and the bearing is installed on the adjusting block.
 Among them, the lower template and the side are detachably connected, for example, the lower template and the side are assembled by screws, which is convenient for maintenance and disassembly.
 The vacuum system and the system for supplying thermal fluid can be placed on the base under the lower template, and a single base can be designed with double stations.
 The description of the known technology is omitted in the text.