Stirring shaft of ice cream machine

Abstract

The novel ice cream machine stirring shaft design overcomes the defects that an existing stirring shaft is insufficient in heat exchange efficiency, weak in conveying capacity, unstable in operation, difficult to clean and maintain, high in cost and the like, and inherits the advantages of existing design. The technical scheme of the invention is characterized in that a spiral scraper (Figure 5) with a clamping groove is arranged on a spiral body (Figure 6) with a fixing pin. Compared with the prior art, the stirring shaft disclosed by the invention has the advantages of high heat exchange efficiency, good product production continuity, better product quality, stable operation and convenience in cleaning and maintenance.

Description

Technical Field

[0001] The present invention relates to the technology of food processing machinery, and particularly to the design and manufacturing technology of a stirring shaft of an ice cream machine Background Art

[0002] The stirring shaft (also known as the stirrer or auger) is a key component of an ice cream machine. The stirring shaft not only needs to extrude the ice cream but also play a role in increasing heat exchange. In actual production, the design of the stirring shaft plays a decisive role in the product quality and production efficiency. The existing relatively mature designs of the stirring shaft are as follows:

[0003] 1. Nylon stirring shaft ( Figure 1 ), a stirring shaft formed by injection molding. Its advantages are simple structure and low manufacturing cost. The disadvantages are low heat exchange efficiency, inability to fully fit the refrigeration cylinder due to low-temperature shrinkage, poor overrun and fineness of the ice cream, possible expansion and locking of the stirring shaft due to frictional heat generation during cleaning, resulting in mechanical failures, and only the whole can be replaced after wear.

[0004] 2. Stirring shaft with a flat scraper installed ( Figure 2 ), a stirring shaft formed by welding a single helix and a support member, with one or more plastic scrapers distributed axially. The advantage is that the scraper automatically presses tightly against the inner wall of the refrigeration cylinder when rotating, which can maximize the heat exchange efficiency and help improve the output and fineness of the ice cream. The disadvantage is that only one scraper can be placed on a single circumference to ensure the conveying capacity and normal fitting of the scraper, and a rocking moment will be generated during operation, which needs to be strengthened in design or a support structure needs to be set up to suppress it. When there is overload or installation error, abnormal wear is likely to occur.

[0005] 3. Stirring shaft with a scraping strip installed ( Figure 3 ), a stirring shaft with two helices symmetrically distributed, and two plastic scraping strips are fixedly covered on the helices. The advantages are that the scraping strip fits tightly with the inner wall of the refrigeration cylinder, resulting in good heat exchange effect, high overrun and fineness of the ice cream, and stable operation and strong conveying performance of the stirring shaft. The disadvantages are that the gap between the scraping strip and the helix cannot be effectively cleaned, it is inconvenient to replace after wear, and special tools or special skills are required for disassembly and assembly.

[0006] 4. Precision stirring shaft ( Figure 4 ), a stirring shaft with two helices symmetrically distributed, and the helix itself plays a role similar to that of a scraper by controlling the fitting accuracy between the stirring shaft and the refrigeration cylinder. The advantages are simple structure, stable operation and strong conveying performance, and no problem of scraper wear. The disadvantages are that the stirring shaft cannot fully fit the wall of the refrigeration cylinder, resulting in poor heat exchange efficiency; high precision control requirements and high processing cost; once deformed by external force or the positioning bushing wears, it will cause serious damage to the stirring shaft and the refrigeration cylinder. Summary of the Invention

[0007] The present invention relates to a new design of the stirring shaft of an ice cream machine, aiming to solve the disadvantages of the existing stirring shaft, such as insufficient heat exchange efficiency, weak conveying capacity, unstable operation, difficult cleaning and maintenance, and high cost, and inherit the advantages of the existing design.

[0008] To achieve the above object, the technical solution of the present invention is: an ice cream machine stirring shaft, characterized in that: 1. a spiral scraper with a card slot ( Figure 5 ); 2. a spiral body with a fixing pin ( Figure 6 ).

[0009] Compared with the prior art, the stirring shaft design of the present invention has the following advantages:.

[0010] 1. The cutting edge of the scraper elastically fits the refrigerating cylinder to ensure effective scraping and high heat exchange efficiency.

[0011] 2. The scraper and the spiral body together form a spiral surface, which does not hinder the conveying and has good product continuity.

[0012] 3. It effectively reduces the shear of the milk slurry, making the texture of the product more dense and smooth.

[0013] 4. The spiral bodies on both sides are symmetrically distributed, the scraper is evenly stressed, the operation is stable, and the overload resistance is strong.

[0014] 5. The scraper can be easily disassembled, the cleaning has no dead corners, and it is convenient to replace after wear.

[0015] 6. The structure is simple and the production efficiency is high. Description of the Drawings

[0016] Figure 1 Nylon stirring shaft.

[0017] Figure 2 Stirring shaft with flat scraper installed.

[0018] Figure 3 Stirring shaft with scraping strip installed.

[0019] Figure 4 Precision stirring shaft.

[0020] Figure 5 Spiral scraper with card slot.

[0021] Figure 6 Spiral body with fixing pin.

[0022] Figure 7 Stirring shaft of the present invention. Detailed Embodiment

[0023] As Figure 7As shown in the figure, the main body of the stirring shaft of the present invention is composed of a spiral body, support pieces (or support rings), a bottom plate and spiral blades welded together. An eccentric shaft or a central rod can be installed in the center. A plurality of identical spiral scrapers are continuously installed on the spiral body end to end through fixing pins. The spiral body is cast and can withstand high torque. The fixing pins are distributed on the spiral body according to the positions required by the scrapers. The support pieces are used to maintain the distance between the two spiral bodies, keep the radial dimension stable, and at the same time play the role of fixing the eccentric shaft or the central rod. The spiral blades mainly provide continuous and stable extrusion ability, and the central hole also plays a positioning role. Highlights of the present invention

[0024] The present invention designs a spiral scraper with a card slot. The scraper is made of polyurethane, and its cross-sectional shape is a T-shaped letter.

[0025] The scraper is installed on the spiral body through two card slots. The opening of the card slot is smaller than the diameter of the fixing pin, and the bottom hole is larger than the fixing pin. When installing, the fixing pin is embedded in the card slot.

[0026] The relationship between the axial length covered by the scraper and the circumferential angle is consistent with that of the spiral body.

[0027] The circumferential diameter of the cross-section where the cutting edge of the scraper is located is larger than the diameter of the refrigeration cylinder. After the stirring shaft is installed, the cutting edge of the scraper always adheres to the wall of the refrigeration cylinder to ensure effective scraping.

[0028] Only one side of each scraper is the cutting edge. To avoid misinstallation, the two card slots are asymmetrically distributed. If installed in reverse, it will cause part conflict and unable to install.

[0029] The cross-sectional angle between the cutting edge of the scraper and the wall of the refrigeration cylinder is 60°, and it can still ensure that the scraper fits tightly under load.

[0030] The present invention designs a spiral body with fixing pins. The spiral body is made of stainless steel, its cross-section is fan-shaped, and one of its side surfaces and the outer arc surface provide support for the spiral scraper.

[0031] There are fixing pins for installing scrapers on one side of the spiral surface. The fixing pins are perpendicular to the spiral surface, and there are limiting steps at the head of the pins.

[0032] The spacing distance of the fixing pins corresponds to the card slots on the scraper. The spacing between the two fixing pins of the same scraper and the spacing between the adjacent fixing pins of two scrapers cannot be the same. The purpose is to prevent misinstallation of the scraper.

[0033] The fixing pins on the two spiral bodies are slightly misaligned. The purpose is to make the scrapers on the two spiral bodies cover each other's installation gaps.

[0034] The thrust direction of the spiral surface on the scraper is away from the center of the circle, that is, when rotating, the spiral body has the effect of squeezing the scraper against the wall of the refrigeration cylinder, which helps the scraper to fit tightly against the refrigeration cylinder.

[0035] The scraper will not fall off after being installed on the spiral body, and there is no dead angle after removal, which is convenient for cleaning and disinfection.

[0036] The two spiral bodies are the main structures of the stirring shaft. To ensure rigidity and appropriate dimensional accuracy, multiple short spiral bodies are spliced on the longer stirring shaft.

Claims

1. An ice cream machine stirring shaft, comprising a scraper (1), a spiral body (2), a support sheet (or a support ring), a bottom plate, a spiral blade and an eccentric shaft (or a center rod), characterized in that: The scraper is mounted on the spiral body.

2. The stirring shaft according to claim 1, characterized in that: The relationship between the axial length and the circumferential angle covered by the scraper is consistent with that of the spiral body.

3. The stirring shaft according to claim 1, characterized in that: The scraper has a cross-sectional shape of the letter T, with one and only one side being a cutting edge (3), and the diameter of the cross-sectional circle where the cutting edge is located is greater than the inner diameter of the refrigeration cylinder.

4. The stirring shaft according to claim 1, characterized in that: The cross section of the spiral body is fan-shaped, and one side surface and the outer arc surface thereof provide support for the scraper.

5. The stirring shaft according to claim 1 or 4, characterized in that: A fixing pin (4) is provided on one side of the spiral body. The fixing pin is perpendicular to the spiral surface, and a limiting step (5) is provided on the pin head.

6. The stirring shaft according to claim 1, 2 or 3, characterized in that: Each scraper has two slots (6), the positions of the slots are asymmetric relative to the center of the scraper, the slot opening is smaller than the diameter of the fixing pin, and the bottom hole is larger than the fixing pin.

7. The stirring shaft according to claim 5 or 6, characterized in that: The position of the fixing pin corresponds to the slot on the scraper, and the spacing distance between two fixing pins installed on the same scraper is different from the spacing distance between adjacent fixing pins of the two scrapers.

8. The stirring shaft according to claim 5 or 6, characterized in that: There is an overall misalignment of the fixing pins on the two spirals.

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