Double-arc small experimental animal fixing forceps

Abstract

The utility model discloses a double arc small experimental animal fixing forceps belongs to experimental animal auxiliary equipment field. The device is by handle part, articulates and clamps the part and constitutes. Handle part is the annular 304 stainless steel structure of diameter 20-30mm, the built-in axle pin of articulates, connects handle part and clamps the part, makes it open and close, clamps the part and adopts double arc curved surface, forms the grading fixed area of adaptation animal neck (diameter 8-12mm) and head (diameter 12-16mm) when closing, and the arc edge is round angle (radius >=1mm). The total length of device is 120-200mm, and the material meets ISO10993 biological compatibility standard. The device realizes head and neck grading non - damage fixing through double arc structure, and promotes experimental efficiency and operating safety.

Description

Technical Field

[0001] This utility model relates to the field of laboratory animal auxiliary equipment technology, specifically to a neck and head fixation device suitable for small laboratory animals such as mice and rats, and more specifically to a double-arc small laboratory animal fixation clamp. Background Technology

[0002] In biomedical and pharmaceutical experimental fields, immobilizing small laboratory animals (such as mice and rats) is a necessary prerequisite for procedures such as drug administration, sampling, and dissection. Traditional laboratory animal immobilization tools mainly have the following problems:

[0003] 1. Limited fixation methods: These methods often use a single clamping surface or rigid constraint structure, which can only fix a certain part of the animal (such as the neck or head), making it difficult to restrict head and neck movement at the same time, leading to the animal struggling and escaping, which affects the efficiency of the experiment.

[0004] 2. High risk of animal injury: The clamping surfaces are mostly flat or sharp-angled, and the pressure is concentrated in a local area when clamping, which can easily cause injuries such as neck congestion and skin scratches in animals, which does not comply with the ethical standards for laboratory animals (such as "reduce injury" in the 4R principle).

[0005] 3. Poor biocompatibility: Ordinary carbon steel is easily corroded by disinfectants (such as alcohol and iodine), has a rough surface, and is prone to residual biological fluids, posing a risk of cross-contamination and failing to meet the requirements for aseptic operation in the laboratory.

[0006] 4. High risk of injury to experimenters: When experimenters restrain mice by hand, the mice have a stress defense instinct and may exhibit aggressive behavior, posing a direct threat to the safety of the experimenters.

[0007] Therefore, a small laboratory animal restraint tool that combines stability, safety, convenience, and biocompatibility is needed. Utility Model Content

[0008] I. Purpose

[0009] To address the problems of insecure fixation, easy damage to animals, insufficient biosafety, and high risk of injury to laboratory personnel in existing technologies, this utility model provides a double-arc small laboratory animal fixation clamp. Through a graded clamping structure, it achieves non-damaging and stable fixation of the animal's neck and head, improving the safety and efficiency of experimental operations, while meeting the ethical and biosafety requirements for laboratory animals.

[0010] II. Technical Solution

[0011] A double-arc-shaped small laboratory animal fixation clamp includes a handle portion 1, a hinge portion 2, and a clamping portion 3, such as... Figure 1 , Figure 2 , Figure 3 As shown, the specific structure is as follows:

[0012] 1. Handle part 1:

[0013] It adopts a ring structure with a ring diameter of φ20-30mm, which is suitable for adults to hold with one hand. The surface is polished (roughness ≤Ra0.8μm).

[0014] Made of 304 stainless steel, it meets biocompatibility standards (ISO10993) and can withstand high-temperature sterilization (121℃, 30 minutes) and alcohol wiping disinfection.

[0015] 2. Hinge 2:

[0016] Located 70-150mm from the end of the handle part 1, the handle part 1 is connected to the clamping part 3 by a stainless steel pin 8 (diameter φ1.5-3mm).

[0017] 3. Clamping part 3:

[0018] The structure employs a double-arc curved surface, forming two circular fixed areas at the front and rear when closed.

[0019] The first arc-shaped area 4 at the rear (neck fixation area): diameter φ8-12mm, radius of curvature R4-6mm. After the clamping part 3 is closed, there is a certain gap between the rounded edges 6 of the first arc-shaped area 4, which is adapted to the physiological curve of the neck of animals such as mice (neck diameter about 8-10mm) and rats (neck diameter about 10-12mm).

[0020] The front second arc-shaped area 5 (head fixing area): diameter φ12-16mm, radius of curvature R6-8mm, adapted to the animal head (slightly larger than the neck). After the clamping part 3 is closed, there is a certain gap between the rounded edges 6 of the second arc-shaped area 5. The distance between the first arc-shaped area 4 and the second arc-shaped area 5 is 5-10mm, and they are connected by a smooth transition surface 7 with a radius of R60mm.

[0021] The rounded corners of the 6-inch plate are rounded (radius ≥ 1 mm) to form a non-sharp clamping surface, ensuring surface contact (contact area ≥ 150 mm²) when in contact with the animal's body surface, dispersing clamping pressure (pressure ≤ 0.5 MPa), and avoiding scratches or pressure damage.

[0022] 4. Overall Structure:

[0023] The total length of the clamp is 120-200mm. The components are assembled by argon arc welding and passivation treatment or by threaded connection (using medical-grade stainless steel bolts). The overall weight is 25-50g. It is ergonomically designed and does not cause fatigue during long-term operation.

[0024] III. Advantages and Positive Effects

[0025] 1. Graded fixation, stable and without damage:

[0026] The double-arc structure precisely matches the size differences of the animal's head and neck, restricting both the neck and head, limiting the animal's left and right swinging, forward and backward stretching, and 360° rotation.

[0027] The non-sharp curved surface and surface contact design ensures uniform distribution of clamping pressure. Experiments have verified that the incidence of neck pinching and bruising in animals is significantly reduced after using this device.

[0028] 2. Highly efficient, safe and convenient to operate:

[0029] The handle opening / closing operation can be completed with one hand, and it takes ≤5 seconds to fix a mouse on average (15-20 seconds with traditional tools or by hand), which significantly improves the efficiency of experimental preparation.

[0030] The ring-shaped handle design enhances grip stability and maintains good maneuverability when operating with gloves (such as nitrile gloves), reducing the risk of animal bites (90% improvement in operator hand protection).

[0031] 3. Biosafe, durable and easy to maintain:

[0032] The 304 stainless steel material can withstand routine disinfection treatments (including 75% alcohol, chlorine-containing disinfectant, and high-pressure steam sterilization), and its biocompatibility tests (cytotoxicity test and sensitization test) all meet the ISO10993 standard, avoiding experimental contamination. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of a double-arc-shaped small laboratory animal fixation clamp according to the present invention;

[0034] Figure 2 This is a schematic diagram of the structure of a double-arc-shaped small laboratory animal fixation clamp of the present invention;

[0035] Figure 3 This is a cross-sectional view AA of the hinge part of a double-arc-shaped small experimental animal fixation clamp according to this utility model.

[0036] Legend:

[0037] 1. Handle; 2. Hinge; 3. Clamping part; 4. First arc-shaped area; 5. Second arc-shaped area; 6. Rounded corner edge; 7. Transition surface; 8. Shaft pin. Detailed Implementation

[0038] I. Best Practices Example Figure 1 , Figure 2 , Figure 3 As shown:

[0039] (a) Component parameters

[0040] part Material Key dimensions Surface treatment Features Handle part 1 304 stainless steel Ring diameter 20-30mm Polishing, pickling and passivation Easy to hold with one hand, easy to clean, and corrosion resistant. Hinge 2 304 stainless steel 2mm in diameter, 5mm in length Polishing, pickling and passivation High wear resistance and corrosion resistance Clamping part 3 304 stainless steel Total length 30mm Polishing, pickling and passivation Double-curved surface reduces animal injury

[0041] (II) Processing Technology

[0042] Handle 1: It adopts a cold-forged ring structure, with a polished and pickled surface, which is easy to clean and corrosion resistant.

[0043] Clamping part 3: The steel bar is bent into a double arc surface by a bending machine. The rounded corner edge 6 of the arc surface is rounded (R1.5mm) to ensure smoothness without sharp edges. The distance between the first arc area 4 and the second arc area 5 is 5-10mm, and they are connected by a smooth transition surface 7 with a radius of R60mm.

[0044] Assembly: The handle part 1 and the clamping part 3 are hinged by the shaft pin 8. The end of the shaft pin 8 is deformed by pressure to prevent the hinge part 2 from coming off. All parts of the clamping part 3 are connected by argon arc welding and pickled and passivated.

[0045] (III) Usage Steps

[0046] Open state: Open handle 1 and use your fingers to control the handle to open, creating an opening and closing space larger than the size of the animal's head and neck;

[0047] Fixed operation: Hold the handle with your left hand, with your thumb and index finger passing through the ring handle, and your middle finger pressing against the rear side of the hinge 2 to close the clamping part 3;

[0048] Align the clamping part 3 with the back of the mouse's neck and slowly move it until the neck (first arc-shaped area 4) and the head (second arc-shaped area 5) are respectively in contact, ensuring that the curved surface completely covers the head and neck;

[0049] The right hand can be used to perform drug administration, gavage, and other operations simultaneously. At this time, the animal's head movement range is ≤5mm and the axial movement distance of the neck is ≤3mm.

[0050] Release procedure: Loosen handle 1, use your fingers to open the handle to release the animal from its restraints. The animal can then detach freely. The entire process does not require contact with the animal's body, thus avoiding stress reactions.

[0051] II. Variant Implementation

[0052] Material variation: The clamping part 3 can be replaced with medical-grade titanium alloy (such as Ti-6Al-4V), which has a lower density (4.5g / cm³) and a 30% weight reduction, making it suitable for long-term, high-frequency operation scenarios.

[0053] Size adjustment: For larger animals such as guinea pigs, the diameter of the first arc area 4 can be increased to 12-14mm, and the diameter of the second arc area 5 can be increased to 16-20mm. Multi-species adaptation can be achieved by replacing the clamping parts 3 with different specifications.

[0054] Surface treatment variation: The surface of clamping part 3 can be sprayed with a medical-grade polytetrafluoroethylene coating (thickness 5-10μm) to further reduce the surface friction coefficient (μ≤0.1) and reduce animal hair adhesion.

[0055] III. Verification of Technical Effects

[0056] Fixation stability test: 50 C57BL / 6 mice (weighing 20-25g) were fixed and the number of escape attempts was recorded: the escape rate of this device was 2% (1 / 50), while the escape rate of the traditional tool was 34% (17 / 50), and the difference was significant (P<0.01).

[0057] Comparison of safety among laboratory personnel:

[0058] Hand-grabbing group: When experimental novices grasped the skin of the head and neck of C57BL / 6 mice with their bare hands, the bite rate was 80% (40 / 50).

[0059] In the capture group using this device: when the experimental novices used this device to capture the skin on the head and neck of C57BL / 6 mice, none of them were bitten.

[0060] Animal injury assessment: After 30 minutes of fixation, the neck skin was observed. No bruising or scratches were found in the device group (0 / 50), while the incidence of bruising in the traditional tool group was 38% (19 / 50), demonstrating that the non-sharp curved surface effectively reduces physical injury.

[0061] Operational efficiency comparison: Skilled operators used this device to fix a single C57BL / 6 mouse in an average of 4.2 seconds, while the average time using traditional tools was 18.5 seconds, increasing efficiency by 4.4 times (time of traditional tools / time of this device).

[0062] This invention systematically solves the defects of existing laboratory animal fixation tools through a double-arc structure and medical-grade materials and processes. It has significant practicality and innovation, and can be widely used in laboratory animal operations, veterinary clinical examinations and other scenarios.

Claims

1. A double-arc-shaped small laboratory animal fixation clamp, characterized in that: Handle (1), hinge (2), clamping part (3), first arc-shaped area (4), second arc-shaped area (5), rounded edge (6); the handle (1) is a ring structure and is made of 304 stainless steel; the hinge (2) is located 70-150mm from the end of the handle (1) and is connected to the clamping part (3) by a stainless steel shaft pin, so that the clamping part (3) can open and close around the hinge point; the clamping part (3) is a double arc-shaped curved surface structure, which forms a first arc-shaped area (4) that fits the neck of a small experimental animal and a second arc-shaped area (5) that fits the head when closed. After the clamping part (3) is closed, there is a certain gap between the rounded edges (6) of the two arc-shaped areas, and the rounded edges (6) are rounded.

2. The double-arc-shaped small laboratory animal fixation clamp according to claim 1, characterized in that: The handle (1), hinge (2) and clamping (3) are all passivated and have a surface roughness ≤ Ra0.8μm.

3. The double-arc-shaped small laboratory animal fixation clamp according to claim 1, characterized in that: The surface is pickled and passivated to ensure long-term use under humid and disinfection conditions.

4. The double-arc miniature laboratory animal fixation clamp according to claim 1, characterized in that: The small experimental animals are mice, rats, or guinea pigs.

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