Medical swing saw based on equal-width cam mechanism

Abstract

The invention discloses a medical swing saw based on an equal-width cam mechanism. The medical swing saw comprises a machine body, a cutter and the equal-width cam mechanism. The swing driven piece is provided with a shaft hole and a plurality of protrusions evenly distributed around the shaft hole in the circumferential direction. The machine body comprises a machine base, an upper gland and a lower gland which are in threaded connection, the machine base is provided with a through axial stepped hole, the upper gland is provided with a groove matched with the swing follower and the cutter, and a pressure spring, the machine base, the swing follower and the cutter penetrate through the upper gland and the lower gland; and when the cutter is pressed, the pressure spring is propped between the stepped surface of the stepped hole of the base and the rod body of the lower gland, so that the cutter is fixed. A magnetic attraction device is arranged between the machine base and the lower gland, when the cutter is replaced, the upper gland and the lower gland do not slide downwards through attraction force, and therefore the cutter is replaced. According to the medical swing saw, the movement performance of the driven part can be improved. And the mechanical wear in high-frequency motion is reduced. Meanwhile, the transmission mechanism is stable in operation, vibration, mechanical friction and impact noise can be remarkably reduced, and doctors can concentrate on surgical operation.

Description

Technical Field

[0001] The invention belongs to a medical oscillating saw, and in particular relates to a medical oscillating saw based on an equal-width cam mechanism. Background Art

[0002] In surgical operations, especially orthopedic operations, medical oscillating saws are one of the indispensable tools. Medical oscillating saws are mainly used to cut bones and other hard tissues. They are often used in joint replacement, arthroscopic surgery, and joint reconstruction surgery. They are efficient, precise, and safe. At present, the main transmission form of medical oscillating saws is to use an eccentric wheel and its driven parts. The motor drives the eccentric wheel to rotate at high speed, and the driven part realizes high-speed reciprocating swing under the high-speed rotation of the eccentric wheel, and drives the tool to swing, thereby achieving cutting.

[0003] As the most common transmission form in medical oscillating saws, eccentric drive also has some limitations. When the eccentric wheel rotates at high speed, it will generate unbalanced inertial force, causing it to vibrate during operation. These vibrations not only affect the cutting accuracy of the operation, but also may cause unnecessary vibration interference to the patient's surgical area, increasing the risk of surgery. At the same time, due to the mechanical friction and vibration of the eccentric wheel drive system, a lot of noise will be generated during operation. The noise not only affects the quiet environment of the operating room, but may also have an adverse effect on the surgeon's attention and psychological state. Summary of the invention

[0004] In view of the above-mentioned prior art, the present invention provides a medical oscillating saw based on an equal-width cam mechanism, which changes the eccentric wheel transmission in the prior art into an equal-width cam transmission mechanism. Compared with the eccentric wheel, the equal-width cam can improve the motion performance of the follower and reduce the mechanical wear in high-frequency motion. At the same time, the transmission mechanism runs smoothly, which can significantly reduce vibration, mechanical friction and impact noise, reduce interference to patients, and help doctors concentrate on surgical operations.

[0005] In order to solve the above technical problems, the present invention proposes a medical oscillating saw based on an equal-width cam mechanism, comprising a machine body, a tool and an equal-width cam mechanism for driving the tool to swing; the equal-width cam mechanism comprises an equal-width cam and a swinging follower, the swinging end of the swinging follower is provided with an axial hole and a plurality of protrusions uniformly distributed circumferentially around the axis of the axial hole; the end of the tool away from the blade is a circular mounting plate, the circular mounting plate is provided with a mounting hole and positioning holes that are uniformly distributed circumferentially around the axis of the mounting hole and match the shape of the plurality of protrusions on the swinging follower and have a one-to-one corresponding position; the machine body comprises a machine base, an upper pressure cover and a lower pressure cover, the machine base is provided with a through axial stepped hole, the small mouth of the axial stepped hole is on the top, the upper pressure cover comprises a rod body A and an upper cap, the lower pressure cover comprises a rod body B and a lower cap, the tail of the rod body A is a threaded rod, The tail of the rod body B is provided with a threaded hole that matches the threaded rod of the rod body A; the small inner diameter of the axial step 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 loosely matched with the outer diameter of the rod body A; the large inner diameter of the axial step hole is loosely matched with the outer diameter of the rod body B; the bottom surface of the upper cap is provided with a groove that matches the shape of multiple protrusions on the swing follower and corresponds to the position one by one; a magnetic protrusion is provided at the bottom of the machine base, and a depression that matches the magnetic protrusion is provided on the top of the lower cap, and a magnetic block that attracts the magnetic protrusion is provided at the bottom of the depression; a pressure spring, the machine base, the swing follower and the tool are penetrated from bottom to top between the lower pressure cover and the upper pressure cover; the threaded rod of the rod member A is threadedly matched with the threaded hole of the rod member B and screwed in.

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

[0007] The installation hole of the tool is sleeved on the rod A of the upper pressure rod. At the same time, the multiple positioning holes of the tool are sleeved on 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 profile surface of the swing follower contacts the contour curved surface of the equal-width cam.

[0009] An opening groove having a width consistent with the diameter of the mounting hole is arranged on the circular mounting plate from the center of the mounting hole in the opposite direction of the blade.

[0010] The equal-width cam is key-connected to the transmission shaft, and the equal-width cam is fixed to the transmission shaft at both ends of the transmission shaft through lock nuts.

[0011] Compared with the prior art, the present invention has the following beneficial effects:

[0012] (1) Using equal-width cams instead of eccentric wheels has better high-speed performance.

[0013] (2) The equal-width cam mechanism achieves efficient and precise swing control of the saw blade through precise contour design. Compared with the eccentric wheel transmission, 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. Doctors can complete the tool replacement in a short time, reducing surgical interruption time and improving surgical efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0017] Figure 2 yes Figure 1 The structural schematic diagram of the medical oscillating saw shown;

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

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

[0020] Figure 5 yes Figure 1 Exploded view of the equal width cam 1 before being connected to the transmission shaft 4;

[0021] Figure 6 yes Figure 1 A schematic diagram of the connection relationship between the upper pressure cover 51 and the lower pressure cover 52 is shown in FIG.

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

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

[0024] Figure 8-2 yes Figure 1 The structural schematic diagram of the machine body, the lower pressure cover 52 and the lower magnetic block 92 is shown in FIG.

[0025] In the figure:

[0026] 1-Equal Width Cam 2-Swing Follower 21-Inner Profile 22-Protrusion

[0027] 23-shaft hole 3-lock nut 4-driving shaft 51-upper pressure cover

[0028] 52-lower pressure cover 53-groove 6-tool 61-positioning hole

[0029] 62-opening groove 71-axial stepped hole 7-machine base 8-key connection

[0030] 91-magnet protrusion 92-magnet block 10-pressure spring DETAILED DESCRIPTION

[0031] The design concept of the medical oscillating saw based on the equal-width cam mechanism proposed by the present invention is to change the eccentric wheel transmission in the prior art into the equal-width cam transmission. Compared with the eccentric wheel, the equal-width cam can select the motion curve of the follower suitable for high-speed conditions before design, thereby improving the motion performance of the follower. The pressure distribution of the contact surface of the equal-width cam mechanism is uniform, which reduces the mechanical wear in high-frequency motion. At the same time, compared with the unbalanced rotational motion of the eccentric wheel, the smooth operation characteristics of the equal-width cam mechanism can significantly reduce vibration, mechanical friction and impact noise.

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

[0033] like Figure 1 , Figure 2 and Figure 3 As shown, a medical oscillating saw based on an equal-width cam mechanism proposed by the present invention comprises a body 1, a cutter 6 and an equal-width cam mechanism for driving the cutter 6 to swing.

[0034] like Figure 1 As shown, the equal-width cam mechanism includes an equal-width cam 1 and a swing follower 2. The power device inputs power through a transmission shaft 4. A key connection 8 is used between the transmission shaft 4 and the equal-width cam 1. Figure 5 As shown, the two ends of the transmission shaft 4 are locked by the lock nut 3, so that the equal-width cam 1 and the swing follower 2 can be stably matched. The equal-width cam 1 is fixed on the transmission shaft 4, and the inner profile 21 of the swing follower 2 is in contact with the contour surface of the equal-width cam 1. The equal-width cam 1 is in contact with the inner profile of the swing follower 2 on both sides at the same time. Under the action of the equal-width cam 1, the swing follower 2 achieves a maximum movement amplitude of 5°. The swing end of the swing follower 2 is provided with an axial hole 23 and a plurality of protrusions 22 uniformly distributed around the axis of the axial hole 23, which are used for positioning and matching the follower 2, the tool 6, and the upper pressure cover 51, as shown in FIG. Figure 1 and Figure 4 shown.

[0035] like Figure 1As shown, the tool 6 has a circular mounting plate at one end away from the blade, and the circular mounting plate is provided with a mounting hole and positioning holes 61 which are uniformly distributed circumferentially around the axis of the mounting hole and which match the shapes of the multiple protrusions 22 on the swing follower 2 and have corresponding positions one by one.

[0036] The machine body includes a machine base 7, an upper pressure cover 51 and a lower pressure cover 52. The machine base 7 is provided with a through axial stepped hole 71, and the small mouth of the axial stepped hole 71 is on the top; the upper pressure cover 51 includes a rod body A and an upper cap, and the lower pressure cover 52 includes a rod body B and a lower cap. The tail of the rod body A is a threaded rod, and the tail of the rod body B is provided with a threaded hole that matches the threaded rod of the rod body A, such as Figure 6 and Figure 7 The small inner diameter 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 in clearance with the outer diameter of the rod body A; the large inner diameter of the axial stepped hole 71 is in clearance with the outer diameter of the rod body B; Figure 1 and Figure 6 , Figure 7 The bottom surface of the upper cap is provided with grooves 53 which match the shapes of the plurality of protrusions 22 on the swing follower 2 and have corresponding positions one by one. Figure 6 As shown. The multiple protrusions 9 on the swing follower 2 cooperate with the multiple positioning holes 61 provided on the tool 6 and the multiple grooves provided on the upper pressure cover 51, so that the upper pressure cover 51 presses the tool 6 and the swing follower 2 on the machine body. When the cam drives the follower to swing, the swing follower 2 drives the tool 6 and the upper pressure cover 51 to achieve rotational motion through the protrusions 9, as shown. Figure 1 shown.

[0037] During installation, the tool 6 is put on the rod A of the upper pressure rod 51 through the installation hole. At the same time, the multiple positioning holes 6 of the tool 6 are put on 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. The upper pressure cover 51 and the lower pressure cover 52 are connected by threads. The pressure spring 10, the machine base 7, the swing follower 2 and the tool 6 are passed through from bottom to top between the lower pressure cover 52 and the upper pressure cover 51; the threaded rod of the rod A is threadedly matched 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 the present invention, in order to facilitate the installation of the tool 6, an opening groove 62 having a width consistent with the diameter of the installation hole is provided on the circular installation plate from the center of the installation hole in the opposite direction of the blade. Figure 1 shown.

[0039] A magnetic attraction device is provided between the bottom of the base 7 and the lower pressure cover 52, and the magnetic attraction device includes a magnetic protrusion 91 provided at the bottom of the base 7, and a depression provided on the upper surface of the lower cap and matching with the magnetic protrusion 91, and a magnetic block 92 attracted to the magnetic protrusion 91 is provided at the bottom of the depression. Figure 1 , Figure 7 and Figure 8-2 shown.

[0040] When the tool 6 needs to be pressed, the upper pressure cover 51 is pressed downward, and the two ends of the pressure spring 10 are respectively pressed against the step surface of the axial stepped hole of the machine base 7 and the upper end of the rod body B of the lower pressure cover 52, so that the upper pressure cover 51 presses the tool 6 tightly and prevents it from loosening. When the tool 6 needs to be replaced, the lower pressure cover 52 is pushed upward to make the magnetic block 92 adsorb to the magnetic protrusion 91, and the upper and lower pressure covers 51 and 52 do not slide downward by the adsorption force, so as to achieve 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 above-mentioned specific embodiments, which are merely illustrative rather than restrictive. Under the guidance of the present invention, ordinary technicians in this field can make many improvements and changes without departing from the purpose of the present invention, which are all within the protection of the present invention.

Claims

1. A medical oscillating saw based on an equal-width cam mechanism, comprising a body and a cutter, characterized in that: It also includes an equal-width cam mechanism for driving the tool to swing; The equal-width cam mechanism comprises an equal-width cam (1) and a swing follower (2), wherein the swing end of the swing follower (2) is provided with an axial hole (23) and a plurality of protrusions (22) uniformly distributed in the circumferential direction around the axis of the axial hole (23); The end of the tool (6) away from the blade is a circular mounting plate, the circular mounting plate being provided with a mounting hole and positioning holes (61) which are uniformly distributed around the axis of the mounting hole and which match the shapes of the plurality of protrusions (22) on the swing follower (2) and have corresponding positions one to one; The machine body comprises a machine base (7), an upper pressure cover (51) and a lower pressure cover (52); the machine base (7) is provided with a through axial stepped hole (71), the small opening of the axial stepped hole (71) is on the top; the upper pressure cover (51) comprises a rod body A and an upper cap; the lower pressure cover (52) comprises a rod body B and a lower cap; the tail of the rod body A is a threaded rod; the tail of the rod body B is provided with a threaded hole matching the threaded rod of the rod body A; The small inner diameter 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 in clearance match with the outer diameter of the rod body A; the large inner diameter of the axial stepped hole (71) is in clearance match with the outer diameter of the rod body B; The bottom surface of the upper cap is provided with grooves (53) that match the shapes of the plurality of protrusions (22) on the swing follower (2) and have corresponding positions one by one; A magnetic protrusion (91) is provided at the bottom of the base (7), a depression matching the magnetic protrusion (91) is provided on the top of the lower cap, and a magnetic block (92) attracted to the magnetic protrusion (91) is provided at the bottom of the depression; A pressure spring (10), the machine base (7), a swing follower (2) and a tool (6) are inserted from bottom to top between the lower pressure cover (52) and the upper pressure cover (51); the threaded rod of the rod A is threadedly matched with the threaded hole of the rod B and is screwed in.

2. The medical oscillating saw according to claim 1, characterized in that: The mounting hole of the tool (6) is sleeved on the rod A of the upper pressure rod (51), and at the same time, the multiple positioning holes (6) of the tool (6) are sleeved on the multiple protrusions (22) of the swing follower (2), and 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 a transmission shaft (4), and the inner profile surface (21) of the swing follower (2) is in contact with the contour curved surface of the equal-width cam (1).

4. The medical oscillating saw according to claim 1, characterized in that: An opening groove (62) having a width consistent with the diameter of the mounting hole is provided on the circular mounting plate from the center of the mounting hole in 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 connection (3), and the equal-width cam (1) is fixed to the transmission shaft (4) at both ends of the transmission shaft (4) via lock nuts (3).

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