A medical oscillating saw based on an equal-width cam mechanism

Abstract

This invention discloses a medical oscillating saw based on an equal-width cam mechanism, comprising a body, a blade, and an equal-width cam mechanism. The oscillating follower has a shaft hole and multiple protrusions evenly distributed around the shaft hole. The body includes a base and threaded upper and lower pressure plates. The base has a through-hole axial stepped hole, and the upper pressure plate has a groove that cooperates with the oscillating follower and the blade. A pressure spring, the base, the oscillating follower, and the blade pass through the upper and lower pressure plates. When the blade is clamped, the pressure spring presses against the stepped surface of the stepped hole in the base and the rod of the lower pressure plate, fixing the blade. A magnetic attraction device is provided between the base and the lower pressure plate; when changing the blade, the attraction force prevents the upper and lower pressure plates from sliding downwards, thus allowing for blade replacement. This medical oscillating saw improves the motion performance of the follower and reduces mechanical wear during high-frequency motion. Simultaneously, the transmission mechanism operates smoothly, significantly reducing vibration, mechanical friction, and impact noise, helping doctors concentrate on surgical procedures.

Description

Technical Field

[0001] This invention relates to a medical oscillating saw, specifically a medical oscillating saw based on an equal-width cam mechanism. Background Technology

[0002] In surgical procedures, especially orthopedic surgery, the medical oscillating saw is an indispensable tool. Primarily used for cutting bone and other hard tissues, it is commonly employed in joint replacement, arthroscopic, and joint reconstruction surgeries, characterized by its high efficiency, precision, and safety. Currently, the main transmission mechanism of the medical oscillating saw utilizes an eccentric wheel and its driven component. A motor drives the eccentric wheel to rotate at high speed, causing the driven component to oscillate rapidly, which in turn drives the cutting tool to swing, thus achieving the cutting action.

[0003] Eccentric wheel drive, currently the most common transmission form in medical oscillating saws, also has some limitations. When the eccentric wheel rotates at high speed, it generates unbalanced inertial forces, causing vibrations during operation. These vibrations not only affect the cutting accuracy of the surgery but may also cause unnecessary vibration interference to the patient's surgical area, increasing surgical risks. Simultaneously, due to the mechanical friction and vibration of the eccentric wheel drive system, it generates significant noise during operation. This noise not only affects the quiet environment of the operating room but may also adversely affect the surgeon's concentration and psychological state. Summary of the Invention

[0004] To address the aforementioned shortcomings of the prior art, this invention provides a medical oscillating saw based on an equal-width cam mechanism. It replaces the eccentric wheel drive in the prior art with an equal-width cam drive mechanism. Compared to an eccentric wheel, the equal-width cam improves the motion performance of the driven component, reducing mechanical wear during high-frequency motion. Simultaneously, the transmission mechanism operates smoothly, significantly reducing vibration, mechanical friction, and impact noise, minimizing interference with the patient and allowing the surgeon to concentrate on the surgical procedure.

[0005] To address the aforementioned technical problems, this invention proposes a medical oscillating saw based on an equal-width cam mechanism, comprising a body, a cutting tool, and an equal-width cam mechanism that drives the cutting tool to oscillate. The equal-width cam mechanism includes an equal-width cam and an oscillating follower. The oscillating follower has an axial hole at its oscillating end and multiple protrusions evenly distributed circumferentially around the axial hole. The end of the cutting tool furthest from the blade is a circular mounting plate. The circular mounting plate has a mounting hole and positioning holes evenly distributed circumferentially around the axis of the mounting hole, matching the shape and position of the multiple protrusions on the oscillating follower. The body includes a base, an upper pressure cover, and a lower pressure cover. The base has a through axial stepped hole with the smaller opening at the top. The upper pressure cover includes a rod A and an upper cap, and the lower pressure cover includes a rod B and a lower cap. The tail of rod A is a threaded rod. The tail of rod B is provided with a threaded hole that mates with the threaded rod of rod A; the inner diameter of the small opening of the axial stepped hole, the inner diameter of the shaft hole of the swing follower, and the inner diameter of the mounting hole on the circular mounting plate are all clearance-fitted with the outer diameter of rod A; the inner diameter of the large opening of the axial stepped hole is clearance-fitted with the outer diameter of rod B; the bottom surface of the upper cap is provided with grooves that match the shape of multiple protrusions on the swing follower and are positioned one-to-one; the bottom of the base is provided with a magnetic protrusion, the top of the lower cap is provided with a recess that matches the magnetic protrusion, and the bottom of the recess is provided with a magnetic block that attracts the magnetic protrusion; a pressure spring, the base, the swing follower, and the cutter pass through from bottom to top between the lower pressure cover and the upper pressure cover; the threaded rod of rod A is threadedly engaged with the threaded hole of rod B and screwed in.

[0006] Furthermore, in the medical oscillating saw of the present invention:

[0007] The mounting hole of the cutting tool is fitted onto the rod A of the upper pressure rod. At the same time, the multiple positioning holes of the cutting tool are fitted onto the multiple protrusions of the swing follower. The multiple protrusions of the swing follower pass through the multiple positioning holes and are embedded in the multiple grooves on the bottom surface of the upper cap.

[0008] The equal-width cam is fixed on the transmission shaft, and the inner contour surface of the oscillating follower contacts the contour surface of the equal-width cam.

[0009] The circular mounting plate has an opening groove with a width consistent with the diameter of the mounting hole, extending from the center of the mounting hole along the opposite direction of the blade.

[0010] The equal-width cam is connected to the drive shaft by a key, and the two ends of the drive shaft are fixed to the equal-width cam by lock nuts.

[0011] Compared with the prior art, the beneficial effects of the present invention are:

[0012] (1) Using a cam of equal width instead of an eccentric wheel results in better high-speed performance.

[0013] (2) The equal-width cam mechanism achieves efficient and precise oscillation control of the saw blade through precise contour design. Compared with eccentric wheel drive, the equal-width cam mechanism reduces mechanical friction and energy loss, and improves transmission efficiency.

[0014] (3) The equal-width cam mechanism operates smoothly with less mechanical friction and impact noise, which significantly reduces vibration and noise during operation.

[0015] (4) The clamping device design makes the tool replacement process simpler and faster, allowing doctors to complete the tool replacement in a short time, reducing surgical interruption time and improving surgical efficiency. Attached Figure Description

[0016] Figure 1 This is an exploded view of the overall structure of the medical oscillating saw of this invention;

[0017] Figure 2 yes Figure 1 The diagram shows the structure of a medical oscillating saw.

[0018] Figure 3 yes Figure 2 The front view of the medical oscillating saw shown;

[0019] Figure 4 yes Figure 2 A schematic diagram of the equal-width cam 1 and the follower 2 shown in the figure;

[0020] Figure 5 yes Figure 1 An exploded view of the equal-width cam 1 before it is connected to the drive shaft 4;

[0021] Figure 6 yes Figure 1 A schematic diagram showing the connection relationship between the upper pressure cover 51 and the lower pressure cover 52 shown in the figure;

[0022] Figure 7 yes Figure 2 A partial sectional view of the machine body section cut by the P-section plane;

[0023] Figure 8-1 yes Figure 1 A schematic diagram of the structure of the main body, the lower pressure cover 52, and the magnetic block protrusion 91 shown in the figure;

[0024] Figure 8-2 yes Figure 1 The diagram shows the structure of the main body, the lower pressure cover 52, and the lower magnetic block 92.

[0025] In the picture:

[0026] 1-Equal width cam 2-Oscillating follower 21-Inner profile 22-Protrusion

[0027] 23-Shaft hole 3-Lock nut 4-Drive shaft 51-Upper pressure cover

[0028] 52-Lower pressure cap 53-Groove 6-Cut tool 61-Positioning hole

[0029] 62-Open slot; 71-Axial stepped hole; 7-Base; 8-Key connection

[0030] 91-Magnetic protrusion; 92-Magnetic block; 10-Compression spring Detailed Implementation

[0031] The design concept of this invention for a medical oscillating saw based on an equal-width cam mechanism is to replace the eccentric wheel drive in existing technologies with an equal-width cam drive. Compared to an eccentric wheel, the equal-width cam allows for the selection of a follower motion curve suitable for high-speed conditions before design, improving the follower's motion performance. The equal-width cam mechanism provides uniform pressure distribution on the contact surface, reducing mechanical wear during high-frequency motion. Furthermore, compared to the unbalanced rotational motion of an eccentric wheel, the smooth operation of the equal-width cam mechanism significantly reduces vibration, mechanical friction, and impact noise.

[0032] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the following embodiments are by no means intended to limit the present invention.

[0033] like Figure 1 , Figure 2 and Figure 3 As shown, the present invention proposes a medical oscillating saw based on an equal-width cam mechanism, comprising a body 1, a cutting tool 6, and an equal-width cam mechanism that drives the cutting tool 6 to oscillate.

[0034] like Figure 1 As shown, the equal-width cam mechanism includes an equal-width cam 1 and a oscillating follower 2. The power unit inputs power through a transmission shaft 4, and the transmission shaft 4 is connected to the equal-width cam 1 by a key 8. Figure 5 As shown, both ends of the drive shaft 4 are locked by lock nuts 3, ensuring stable engagement between the equal-width cam 1 and the oscillating follower 2. The equal-width cam 1 is fixed to the drive shaft 4, and the inner contour surface 21 of the oscillating follower 2 contacts the contour surface of the equal-width cam 1. The equal-width cam 1 contacts the inner contour surface of the oscillating follower 2 simultaneously from both sides. Under the action of the equal-width cam 1, the oscillating follower 2 achieves a maximum movement range of 5°. The oscillating end of the oscillating follower 2 is provided with a shaft hole 23 and multiple protrusions 22 evenly distributed circumferentially around the shaft hole 23, used for positioning and engagement of the follower 2, the tool 6, and the upper pressure cover 51. Figure 1 and Figure 4 As shown.

[0035] like Figure 1As shown, the cutting tool 6 has a circular mounting plate at the end away from the blade. The circular mounting plate has mounting holes and positioning holes 61 that are circumferentially distributed around the axis of the mounting holes and whose shapes match the multiple protrusions 22 on the swing follower 2 and whose positions correspond one-to-one.

[0036] The machine body includes a base 7, an upper pressure cover 51, and a lower pressure cover 52. The base 7 has a through axial stepped hole 71, with the smaller opening of the axial stepped hole 71 facing upwards. The upper pressure cover 51 includes a rod A and an upper cap, and the lower pressure cover 52 includes a rod B and a lower cap. The tail of the rod A is a threaded rod, and the tail of the rod B has a threaded hole that mates with the threaded rod of the rod A. Figure 6 and Figure 7 As shown. The inner diameter of the small opening of the axial stepped hole 71, the inner diameter of the shaft hole 23 of the swing follower 2, and the inner diameter of the mounting hole on the circular mounting plate are all clearance-fitted with the outer diameter of the rod A; the inner diameter of the large opening of the axial stepped hole 71 is clearance-fitted with the outer diameter of the rod B; as shown. Figure 1 and Figure 6 , Figure 7 As shown. The bottom surface of the upper cap is provided with grooves 53 that match the shape of multiple protrusions 22 on the swing follower 2 and whose positions correspond one-to-one, such as... Figure 6 As shown. Multiple protrusions 9 on the oscillating follower 2 engage with multiple positioning holes 61 on the cutter 6 and multiple grooves on the upper pressure cover 51, causing the upper pressure cover 51 to press the cutter 6 and the oscillating follower 2 onto the machine body. When the cam drives the follower to oscillate, the oscillating follower 2, through the protrusions 9, drives the cutter 6 and the upper pressure cover 51 to achieve rotational motion, as shown. Figure 1 As shown.

[0037] During installation, the cutter 6 is fitted onto the rod A of the upper pressure rod 51 through the mounting hole. Simultaneously, multiple positioning holes 6 of the cutter 6 are fitted onto multiple protrusions 22 of the swing follower 2. The multiple protrusions 22 of the swing follower 2 pass through multiple positioning holes and are embedded in multiple grooves 53 on the bottom surface of the upper cap. The upper pressure cover 51 and the lower pressure cover 52 are connected by threads. A pressure spring 10, the base 7, the swing follower 2, and the cutter 6 pass through the lower pressure cover 52 and the upper pressure cover 51 from bottom to top. The threaded rod of the rod A is threadedly engaged with the threaded hole of the rod B and screwed in. Figure 1 , Figure 2 , Figure 3 , Figure 6 and Figure 7 As shown,

[0038] In this invention, for ease of installation of the cutting tool 6, the circular mounting plate has an opening groove 62 with a width consistent with the diameter of the mounting hole, extending from the center of the mounting hole along the opposite direction of the cutting tool. Figure 1 As shown.

[0039] A magnetic attraction device is provided between the bottom of the base 7 and the lower pressure cover 52. This magnetic attraction device includes a magnetic protrusion 91 located at the bottom of the base 7 and a recess on the upper surface of the lower cap that matches the magnetic protrusion 91. The bottom of the recess has a magnetic block 92 that attracts the magnetic protrusion 91. Figure 1 , Figure 7 and Figure 8-2 As shown.

[0040] When the tool 6 needs to be clamped, the upper pressure cover 51 is pressed down, and the two ends of the pressure spring 10 are respectively pressed against the stepped surface of the axial stepped hole of the machine base 7 and the upper end of the rod B of the lower pressure cover 52, so that the upper pressure cover 51 firmly presses the tool 6 and prevents it from loosening. When the tool 6 needs to be replaced, the lower pressure cover 52 is pushed up, so that the magnetic block 92 and the magnetic protrusion 91 are attracted to each other. The attraction force prevents the upper and lower pressure covers 51 and 52 from sliding down, thereby realizing the tool replacement.

[0041] Although the present invention has been described above in conjunction with the accompanying drawings, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many improvements and changes under the guidance of the present invention without departing from the spirit of the present invention, and these improvements and changes are all within the protection scope of the present invention.

Claims

1. A medical oscillating saw based on an equal-width cam mechanism, comprising a body and a cutting tool, characterized in that, It also includes a constant-width cam mechanism that drives the tool to swing; The equal-width cam mechanism includes an equal-width cam (1) and a swing follower (2). The swing end of the swing follower (2) is provided with a shaft hole (23) and a plurality of protrusions (22) evenly distributed around the shaft hole (23) in the circumferential direction. The end of the cutting tool (6) away from the blade is a circular mounting plate. The circular mounting plate is provided with mounting holes and positioning holes (61) that are evenly distributed around the axis of the mounting holes and match the shape of multiple protrusions (22) on the swing follower (2) and are in one-to-one correspondence. The machine body includes a base (7), an upper pressure cover (51) and a lower pressure cover (52). The base (7) is provided with a through axial stepped hole (71), with the small opening of the axial stepped hole (71) facing upwards. The upper pressure cover (51) includes a rod A and an upper cap. The lower pressure cover (52) includes a rod B and a lower cap. The tail of the rod A is a threaded rod, and the tail of the rod B is provided with a threaded hole that mates with the threaded rod of the rod A. The inner diameter of the small opening of the axial stepped hole (71), the inner diameter of the shaft hole (23) of the swing follower (2), and the inner diameter of the mounting hole on the circular mounting plate are all clearance-fitted with the outer diameter of the rod body A; the inner diameter of the large opening of the axial stepped hole (71) is clearance-fitted with the outer diameter of the rod body B. The bottom surface of the upper cap is provided with grooves (53) that match the shape of multiple protrusions (22) on the swing follower (2) and are in one-to-one correspondence with each other; The bottom of the base (7) is provided with a magnetic protrusion (91), the top of the lower cap is provided with a recess that matches the magnetic protrusion (91), and the bottom of the recess is provided with a magnetic block (92) that attracts the magnetic protrusion (91). A pressure spring (10), a base (7), a swing follower (2), and a cutting tool (6) pass through the lower pressure cover (52) and the upper pressure cover (51) from bottom to top; the threaded rod of the rod A is threadedly engaged with the threaded hole of the rod B and screwed in.

2. The medical oscillating saw according to claim 1, characterized in that, The mounting hole of the cutter (6) is fitted onto the rod A of the upper pressure cover (51). At the same time, the multiple positioning holes (61) of the cutter (6) are fitted onto the multiple protrusions (22) of the swing follower (2). The multiple protrusions (22) of the swing follower (2) pass through the multiple positioning holes and are embedded in the multiple grooves (53) on the bottom surface of the upper cap.

3. The medical oscillating saw according to claim 1, characterized in that, The equal-width cam (1) is fixed on the transmission shaft (4), and the inner contour surface (21) of the swing follower (2) is in contact with the contour surface of the equal-width cam (1).

4. The medical oscillating saw according to claim 1, characterized in that, On the circular mounting plate, an opening groove (62) with a width consistent with the diameter of the mounting hole is provided from the center of the mounting hole along the opposite direction of the blade.

5. The medical oscillating saw according to claim 1, characterized in that, The equal-width cam (1) and the transmission shaft (4) are connected by a key (3), and the two ends of the transmission shaft (4) are fixed to the equal-width cam (1) by lock nuts (3).

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