A screw for a Varian accelerator fixing bracket

Abstract

The present invention relates to a screw for a Varian accelerator mounting bracket. The screw comprises a nut and a screw rod. The screw rod comprises an integrally formed threaded portion, a rotating portion, and a head. The nut is hollow and defines a circular hole for inserting the screw rod head. A first spring stopper is provided at the bottom end of the head, and a second spring stopper is provided on the inner wall of the circular hole. A spring in a tensioned state is interposed between the first and second spring stops. Compared with existing technologies, the present invention has the advantages of improved accelerator safety, high reliability, and excellent performance.

Description

Technical Field

[0001] The invention relates to the field of accelerator safety maintenance, in particular to a screw used for a Varian accelerator fixing bracket. Background Art

[0002] Currently, the screw securing the bracket to the interface assembly on all Varian accelerator models is a solid metal screw that protrudes from the surface. This makes it easy for clinicians to accidentally collide the rotating gantry with the treatment table when performing off-center patient plans, increasing the risk of machine failure and potentially causing patient injury. The vast majority of these collisions occur at this protruding screw.

[0003] Although most Varian accelerators are equipped with laser anti-collision systems to reduce the probability of collisions, this system has been abandoned by most customers due to design flaws and its incompatibility with domestic usage habits. Summary of the Invention

[0004] The purpose of the present invention is to provide a screw for a Varian accelerator fixing bracket in order to overcome the defects of the above-mentioned prior art.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] A screw for a Varian accelerator fixing bracket comprises a nut and a screw rod. The screw rod comprises an integrally formed threaded portion, a rotating portion and a head. The nut is hollow and has a circular hole for inserting the screw rod head. A first spring stop is provided at the bottom end of the head, and a second spring stop is provided on the inner wall of the circular hole opening. A spring in a stretched state is provided between the first and second spring stops.

[0007] The first spring stopper is embedded in a groove at the outer edge of the bottom end of the head.

[0008] The second spring stopper is embedded in a groove on the inner wall of the circular hole opening.

[0009] The first spring stopper and the second spring stopper are both made of steel.

[0010] The threaded portion is provided with threads, and the threads account for 4 / 5 of the total length of the threaded portion.

[0011] The outer surface of the rotating part is evenly provided with a plurality of planes along the circumference for rotation by a wrench.

[0012] The lower surface of the nut is provided with a fluorescent layer.

[0013] Compared with the prior art, the present invention has the following advantages:

[0014] 1. Improve the safety of the accelerator: reduce the protrusion length (from the original 1cm to about 0.3-0.5mm) to reduce the probability of collision, the spring connection structure reduces the damage caused by collision, and a fluorescent layer is coated on the outside of the nut to enhance the warning effect.

[0015] 2. High reliability: Pure mechanical structure, no electronic components, the product itself has no risk of failure.

[0016] 3. Good use effect: The purpose of the improvement is to enhance safety, and the size and function of the screw core are consistent with the original product. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the present invention.

[0018] Figure 2 Schematic diagram of the cross section of the rotating part.

[0019] Description of the marks in the figure:

[0020] 1. Nut, 11. First spring stopper, 21. Threaded portion, 22. Rotating portion, 23. Head, 231. Second spring stopper, 3. Spring. DETAILED DESCRIPTION

[0021] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] Example

[0023] like Figure 1 As shown, a screw for a Varian accelerator fixing bracket, the thread of the screw fixes the Varian accelerator fixing bracket upward, includes a nut 1 and a screw, the screw includes an integrally formed threaded portion 21, a rotating portion 22 and a head 23, the nut 1 is hollow, and a circular hole is provided for inserting the screw head 23, a first spring stop 11 is provided at the bottom end of the head 23, and a second spring stop 231 is provided on the inner wall of the circular hole opening, a spring 3 in a stretched state is provided between the first spring stop 11 and the second spring stop 231, and under normal conditions, the nut 1 will be retracted by the tension of the spring, so that the height of the nut protrusion becomes smaller.

[0024] The first spring stopper 11 is embedded in the groove at the outer edge of the bottom end of the head 23, and the second spring stopper 231 is embedded in the groove on the inner wall of the circular hole opening. The first spring stopper 11 and the second spring stopper 231 are both arc-shaped stoppers made of steel.

[0025] The threaded portion 21 is provided with threads, which account for 4 / 5 of the total length of the threaded portion 21 , and a 1 / 5 position is reserved at the lower portion for a wrench to twist the rotating portion 22 .

[0026] The outer surface of the rotating portion 22 is uniformly provided with a plurality of planes along the circumference for rotation by a wrench, such as Figure 2 As shown, four planes are opened in this example.

[0027] The lower surface of the nut 1 is provided with a fluorescent layer to remind the user not to touch it in a dimly lit environment, thereby ensuring safety.

[0028] The screw has a coil of spring between the screw body and the screw rod. When not in use, the spring force will make the screw body closer to the machine. When it is needed, you only need to align the bracket socket with the screw. The nut will reach its normal position under the action of gravity and the squeezing of the bracket socket itself.

[0029] When the screw collides, the improved nut is no longer made of solid metal and can quickly break off from the machine, avoiding more serious damage.

Claims

1. A screw for a Varian accelerator fixing bracket, characterized in that: The screw comprises a nut (1) and a screw rod, wherein the screw rod comprises an integrally formed threaded portion (21), a rotating portion (22) and a head (23), the nut (1) being hollow and having a circular hole for inserting the screw rod head (23), a first spring stopper being provided at the bottom end of the head (23), a second spring stopper being provided on the inner wall of the circular hole opening, and a spring (3) in a tensioned state being provided between the first spring stopper and the second spring stopper; The first spring stopper is embedded in a groove at the outer edge of the bottom end of the head (23); The second spring stopper is embedded in a groove on the inner wall of the circular hole; The first spring stopper and the second spring stopper are both made of steel; The threaded portion (21) is provided with a thread, and the thread accounts for 4 / 5 of the total length of the threaded portion (21); The outer surface of the rotating portion (22) is evenly provided with a plurality of planes along the circumference for rotation by a wrench; The lower surface of the nut (1) is provided with a fluorescent layer; Under normal conditions, the nut (1) will be retracted due to the tension of the spring, so that the height of the nut protrusion becomes smaller; When the screw collides, the improved nut is no longer made of solid metal and can quickly break off from the machine, avoiding more serious damage.

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