A universal joint in which the extended portion of a female shaft, which houses a male shaft that can rotate and slide freely, is integrally fixed to a joint yoke or power transmission shaft as a connector for the male shaft, at a position on the centerline of the power transmission rotation, so as to be unable to rotate relative to it.

Abstract

This invention provides a cross-shaped universal joint that suppresses the occurrence of uneven velocity motion. [Solution] The present invention is not a cross-shaft system in which two shafts are fixed in a cross shape and integrated, but a cross-shaft in which two shafts, a male shaft and a female shaft, can rotate and tilt freely from the other shaft while maintaining a cross shape with each other. By fixing the extension part that provides a sliding swing space for the female shaft to the connecting joint yoke or power transmission shaft, the orientation position of the opening of the sliding swing space is set to the optimal position, improving the swinging motion of the male shaft, and stable rotation is also achieved because the extension part, which had a large specific gravity, is integrated with the power transmission shaft.

Description

【Technical Field】 【0001】 The present invention relates to a universal joint. 【Background Art】 【0002】 The cross shaft of the universal joint of a flexible joint can generally transmit rotational power even when connecting the input shaft and the output shaft of a power transmission shaft in a bent state with an angle of about 30 degrees. However, the universal joint, also simply called a cross shaft or a Cardan joint, has a problem of non-uniform speed motion and may cause problems during high-speed rotation. Also, as a countermeasure for non-uniform speed motion in a Cardan joint, a method of double-installing the Cardan joint to cancel non-uniform speed motion is also adopted. 【0003】 Also, in the cross shaft of the cross shaft type universal joint of Patent No. 7701769, in which two shaft rods, a male shaft rod and a female shaft rod orthogonal to the cross, can slide with respect to each other from the other shaft rod and can tilt and swing independently toward the power transmission shaft side, a swinging space is provided in a portion where the middle position of the female shaft rod is expanded in a disk shape or a spherical shape, the male shaft rod housed through the swinging space is rotatable, and further slides in the swinging space to be tilt-swingable in the direction of the power transmission shaft while maintaining the orthogonal angle on the center line of the female shaft rod 13, by enabling the male shaft rod to perform a single tilting operation in the swinging space, the non-uniform speed motion generated by rotating the female shaft rod off-course in the tilting direction is suppressed, when the female shaft rod rotates and tilt-sways with the male shaft rod as an axis, the male shaft rod can rotate and tilt-sway independently without rotating off-course in the tilting direction, thereby suppressing non-uniform speed motion. 【Prior Art Documents】 【Patent Documents】 【0004】 [Patent Document 1] Patent No. 7701769 [Patent Document 2] Patent No. 7353611 [Patent Document 3] Japanese Patent Publication No. 2009-168190 [Patent Document 4] Japanese Patent Application No. 2025-034140 [Overview of the project] [Problems that the invention aims to solve] 【0005】 The problem of the present invention is, The cross shaft, which consists of two shafts, a male shaft and a female shaft, perpendicular to each other in a cross shape, according to Patent 7701769, The two shafts, the male shaft and the female shaft, are rotatable relative to each other, and the male shaft can slide within the sliding part of the female shaft while transmitting rotational power. The male and female shafts can each tilt and oscillate independently toward the power transmission shaft to which they are connected. This cross-shaft universal joint is designed to suppress uneven motion by eliminating unnecessary movement that would cause the other shaft to rotate in the same direction as the other shaft during alternating tilting movements toward the connected power transmission shaft. 【0006】 However, since the individual rotations of the male and female shafts are free, If the orientation of the through-hole opening in the sliding part of the female shaft is not correct during rotational movement for power transmission, the sliding male shaft will come into contact with the end portion of the through-hole opening, causing the male shaft to either be pushed in an inclined direction toward the power transmission shaft side or remain in that position. It is possible that this will place an extra burden on the tilting and oscillating motion of the male shaft. If it remains stationary, it may cause a slight but potentially unequal velocity motion in a fixed, cross-shaped structure. [Means for solving the problem] 【0007】 To solve the above problems, the present invention employs the following means. In claim 1 of the present invention, The input shaft and output shaft of the power transmission shaft A cross-shaped universal joint, which connects two shafts at a bending angle to transmit rotational power, is a cross-shaped universal joint. The two shafts arranged in a cross shape vertically and horizontally on the cross axis are not fixed together, and the cross axis is made up of individual two shafts. One of the separate shafts is attached to the male shaft. The other shaft is used as the female shaft, The male shaft having a single linear structure The male shaft is provided with a retaining portion that prevents separation from the female shaft by having one or more parts of the linear structure protrude from one intermediate position that serves as the center point of power transmission rotation as the cross shaft, The central portion of the female shaft, centered on the intermediate position which is the center point, is expanded in a disc-like or spherical shape on the circumference perpendicular to the center line of the female shaft, The space is provided as a swing space for housing the intermediate portion of the male shaft, extending from the central point on the inside of the expansion portion to the outside of the circumference which is the end of the expansion portion in the orthogonal direction. In a universal joint consisting of a cross shaft, the male shaft is housed within the swing space so as to be rotatable and also so as to be slidable through the swing space, 【0008】 The female shaft and the bifurcated fitting portion of the joint yoke on the power transmission shaft side, which is joined and connected to the female shaft, are fixed together, and the expanded portion is positioned on the center line of the power transmission rotation of the joint yoke so that it cannot rotate relative to it. Alternatively, without providing the linear shaft portion of the female shaft, only the extension portion with the swing space provided on the inside is used as the connecting portion of the female shaft extension type connecting member to the male shaft, and without providing the bifurcated fitting portion on the tip side of the joint yoke, the connecting portion is integrally fixed at a position on the center line of the power transmission rotation at the tip of the joint yoke. Alternatively, a connecting portion fixing base is provided to connect and fix the connecting portion and the power transmission shaft without providing a joint yoke and a linear shaft portion of the female shaft rod, and the power transmission shaft, the connecting portion fixing base, and the connecting portion are integrally fixed on the center line of the power transmission rotation, The middle portion of the male shaft rod is rotatably and slidably swingably accommodated in the swing space so that it can be connected. A universal joint characterized by this is used. 【0009】 In the cross shaft of Patent No. 7701769, each of the male shaft rod 12 and the female shaft rod 13 is configured to swing rotatably from the joint yoke to which each is connected. The slide swing space 20 provided in the female shaft rod 13 extends in a fan shape of 60 degrees or more from the center point of the female shaft rod 13 toward the outer peripheral circumference on both sides in the orthogonal direction on the straight line of the female shaft rod 13 and penetrates. The thickness width of the gap in the space extending in the fan shape is set to a width of substantially the same diameter according to the shape of the male shaft rod 12, and the inclination other than the orthogonal angle direction is not possible. The male shaft rod 12 in the slide swing space 20 can swing with an inclination of about 30 degrees while maintaining the orthogonal angle. The female shaft rod 13 can also rotate and swing with an inclination independently around the male shaft rod 12. 【0010】 In the present invention, In the rotational operation of power transmission, to prevent the deviation of the position of the through-hole openings on both sides of the slide portion provided in the extension portion of the female shaft rod 13 from the optimal position and the position of the male shaft rod 12 housed in the slide portion and sliding in the slide portion, the joint between the female shaft rod 13 and the joint yoke is not rotatable, and the orientation position of the through-hole openings of the slide portion of the female shaft rod 13 is fixed to the joint portion of the intoyoke in the optimal direction position or directly fixed to the power transmission shaft 60 so as to be non-rotatable relative to each other. 【0011】 ​The optimal directional position of the through-hole opening of this slide part is a position where, when the male shaft rod 12 slides, it does not contact the end part of the through-hole opening which is the opening of the slide part of the female shaft rod 13 and does not prevent the slide movement, that is, a position where it can slide around the middle position of the slide movement space of the through-hole opening. 【0012】 As an example of setting the optimal position, in the case where the input shaft and the output shaft of the power transmission shaft face each other upward at the same angle in terms of the refraction angle and are jointed with a cross shaft and a conventional general fork-shaped joint yoke 28, when the shaft rod of the female shaft rod 13 is in a vertical state, when the male shaft rod 12 is in a horizontal state in the lateral direction, there is a method of fixedly connecting the pair of joint parts on the side connected to the female shaft rod 13 so that the shaft of the male shaft rod 12 is at the middle position of the slide movement space of the through-hole opening of the female shaft rod 13 in a non-rotatable manner, etc. 【0013】 Also, in the present invention, by jointing and connecting with the joint yoke of Patent No. 735611 which can connect the input shaft and the output shaft of the power transmission shaft with stable rotation, further stable rotation is intended, the joint yoke is configured to include a joint yoke base, a connecting part, a hinge operating part, and a pair of joint parts integrally fixed to the hinge operating part, the connecting part is configured to be partially housed in a slide space provided in the yoke base and can tilt and swing from the yoke base, the hinge operating part is made hinge-operable from the connecting part, a tip-side configuration including a connecting part 40 that rotates and tilts and swings with the connecting part rotation fulcrum pin 39 provided in the joint yoke base 30 as a fulcrum and a hinge operating part 50 that is hinge-rotatable from the hinge shaft part 41 provided in the connecting part 40, the pair of joint parts are integrally fixed to both tips on the side of the mating power transmission shaft of the hinge operating part, the hinge operating part integrated with the pair of joint parts is configured to be able to be jointed to the shaft rod of the cross shaft in the shape of a fork, The joint yoke base and tip are designed to bend in four directions (front, back, left, and right) to suppress uneven velocity motion during power transmission. By joining a cross made up of a male shaft 12 and a female shaft 13, even smoother power transmission and rotation can be achieved. 【0014】 Furthermore, in Japanese Patent Application No. 2025-034140, regarding the joint yoke of the aforementioned Patent No. 7353611, In order to prevent the hinge operating part, which is integrally fixed with the pair of joint parts in the shape of a bifurcated metal fitting, from bending and tilting excessively from the connecting part beyond an arbitrary angle of inclination such as 30 degrees during hinge operation, An over-bending prevention part for the hinge operating part is provided by adding an inclination angle limiting projection or an inclination angle limiting annular part to any part of the yoke base, the connecting part, or the hinge operating part, When refracted at an angle greater than 30 degrees, If the hinge operating part is provided with an overbending prevention part for the hinge operating part, the overbending prevention part for the hinge operating part and the joint yoke base of the joint yoke, or the connecting part, or the power transmission shaft to which it is joined will come into contact. or If the hinge operating portion is provided with an overbending prevention portion on any part of the joint yoke other than the hinge operating portion, the overbending prevention portion will come into contact with the hinge operating portion to prevent excessive bending. This universal joint is characterized by the following features. 【0015】 The female shaft 13, which is integrally fixed with the pair of joint parts of these joint yokes, is thought to enable even more stable rotation during power transmission. Furthermore, a method to stabilize rotation by integrally fixing the pair of joint parts of this joint yoke is: It is also thought to be effective for the male shaft 12, Since the male shaft 12, which is integrally fixed to the joint, is unable to rotate within the sliding space of the female shaft 13, it will slide without any rolling motion for sliding movement. I believe it is necessary to add new rotation support components, such as bearings, to the male shaft 12. However, the contribution of the male shaft 12, which is integrally fixed with the joint, to stable rotation is considered to be limited compared to the female shaft 13 because its specific gravity is lower. [Effects of the Invention] 【0016】 In Patent No. 7701769, The cross axis of a universal joint is designed so that, unlike the integrated cross axis of a cardan joint which is the main cause of uneven velocity motion, the entire cross axis does not tilt when the two shafts tilt at a bending angle toward their respective power transmission shafts. Two shafts, a male shaft 12 and a female shaft 13, which share the same center point as a cross axis, are inclined toward the power transmission shaft on the connecting side so that they can rotate independently from that center point. The design was made such that the inclination of a single shaft does not affect the whole system, thus preventing the occurrence of uneven velocity motion. 【0017】 In this invention, the female shaft 13, which has a swing space 19, is not rotatable, By integrally fixing the joint yoke on the side connected to the female shaft 13 in the correct direction, The male shaft 12 and the female shaft 13 remain rotatable from their respective center points relative to each other, but the female shaft 13 is oriented in a fixed direction and cannot rotate relative to the joint yoke to which it is joined. When the male shaft rod 12 in the swinging space 19 is tilted twice per rotation of power transmission, with a tilt of approximately 30 degrees or so towards the joint yoke to which it is connected, When the male shaft rod 12 is tilted, it can slide approximately 30 degrees from an intermediate position in the fan-shaped space that extends 60 degrees or more around the expanded portions on both sides, passing through the center point of the female shaft rod 13, toward the through-holes at both ends in two directions, without contacting the ends. 【0018】 Furthermore, the female shaft rod 13, which is equipped with the female shaft intermediate position extension 14, a crucial and heavy part that plays a central role in the present invention, does not rotate freely on its own. By integrally fixing it to the connecting joint yoke side, the power transmission rotation becomes integrated with the power transmission shaft on the connecting side, resulting in even more stable rotation. It is impossible to integrally fix this female shaft 13, or the male shaft 12, to the joint yoke side that connects them, with a conventional integrated-fixing type cross shaft. This is only possible with a cross shaft consisting of a female shaft 13 and a male shaft 12, as described in Patent 7701769, each having a sliding swing space 25 that allows each shaft to tilt freely toward the power transmission shaft side. [Brief explanation of the drawing] 【0019】 [Figure 1] This is a plan view of a cross-shaped shaft consisting of a male shaft 12 and a female shaft 13, two shafts that are perpendicular to each other in a cross shape, and each shaft can tilt and swing independently from the other shaft. [Figure 2] This is a front view of Figure 1. [Figure 3] This is a perspective view of the cross axis in Figures 1 and 2. [Figure 4] This is a perspective view of the entire male shaft rod 12, which was partially shown on the cross axis in Figures 1 to 3. [Figure 5] This is a front view of a joint yoke, also called a bifurcated fitting, which is integrally fixed and connected to the female shaft 13 side of the cross shaft shown in Figures 1 to 3. [Figure 6] This is a side view of Figure 5. [Figure 7] This is a plan view of Figure 5. [Figure 8] This is a bottom view of Figure 5. [Figure 9] This is a side view of a joint yoke, also called a bifurcated fitting, which rotatably connects to the male shaft 12 side of the cross shaft shown in Figures 1 to 4. [Figure 10] This is an embodiment in which the overall orientation of the cross shaft and the female shaft 13 are clearly displayed within the extracted circle indicated by the arrow when the power is transmitted in a rotational motion state by connecting the cross shaft shown in Figures 1 to 4 and the joint yoke shown in Figures 5 to 9. [Figure 11] This is similar to Figure 10, but this embodiment shows the state of the male shaft 12 and female shaft 13 after a quarter rotation from the state position in Figure 10 due to the rotation of the power transmission. [Figure 12] This is an embodiment of the cross-shaped male shaft 12 similar to that in Figure 10, but it shows an embodiment in which the female shaft 13 does not have a rectangular prism portion 16, and the female shaft extension type connecting part 74, which is specialized in the shape and structure of only the female shaft intermediate position extension part 14, is directly connected and fixed integrally with the power transmission shaft 60 on the right side via the connecting part fixing base 76. [Figure 13] This is similar to Figure 12, but this embodiment shows the connection state of the male shaft 12 and the female shaft extension type connecting part 74 after a quarter rotation from the state position in Figure 12 due to the rotation of power transmission. [Figure 14] This is a front view of a four-way bending joint yoke 29 based on Japanese Patent No. 7353611 and Japanese Patent Application No. 2025-034140. [Figure 15] This is a plan view of Figure 14. [Figure 16] This is a side view of Figure 14. [Figure 17] This is a plan view of the male shaft rod 12, which has rectangular prisms at both ends. [Figure 18] This is an embodiment illustrating the rotational operation of power transmission by connecting a cross shaft, which consists of a female shaft rod 13 of the cross shaft shown in Figures 1 to 3 and a male shaft rod 12 of Figure 17 with both end portions being square prisms, to a four-way bending joint yoke 29 shown in Figures 14 to 16. [Figure 19]This is similar to Figure 18, but this embodiment shows the connected state of the male shaft 12 and female shaft 13 after a quarter rotation from the state position in Figure 18 due to the rotation of power transmission. [Figure 20] This is an embodiment similar to Figure 18, but it shows that the female shaft extension type connecting part 74, which does not have the female shaft square prism portion 16 of the female shaft 13, is directly connected and fixed together with the hinge operating part 50 of the four-way bending joint yoke 29 on the lower left side by the connecting part fixing base 76. [Figure 21] This is similar to Figure 20, but this embodiment shows the connected state of the male shaft 12 and female shaft 13 after a quarter rotation from the state position in Figure 20 due to the rotation of the power transmission. [Modes for carrying out the invention] 【0020】 In this invention, The rotational motion of power transmission affects the orientation of the through-holes on both sides of the slide swing space 20 provided in the intermediate position extension portion 14 of the female shaft rod 13, To prevent the position of the male shaft 12, which is housed and sliding within the slide oscillation space 20, from deviating from its optimal position within the slide oscillation space 20, In order to stabilize the rotational movement of the heavy female shaft 13, In this invention, the joint between the female shaft 13, the power transmission shaft 60, and the joint yoke is not rotatable. The female shaft 13 is connected to the power transmission shaft 60 on the connecting side by fixing it integrally with the power transmission shaft 60 on the connecting side so that it cannot rotate relative to the female shaft 13, with the orientation of the through-hole opening of the slide swing space 20 set to the optimal directional position. [Examples] 【0021】 Figures 1 to 4 show a cross shaft of the Patent No. 7701769 type, in which orthogonal shafts can rotate at an angle relative to each other. However, the present invention illustrates a universal joint in which the female shaft 13 of the cross shaft is fixed to the joint yoke in a way that prevents relative rotation, with the male shaft 12 being cylindrical and rotatable, and the female shaft 13 being a rectangular prism and fixed in a way that prevents relative rotation. 【0022】 Figure 1 is a plan view of the cross axis. The central filled rectangle represents the tip 18 of the female shaft rectangular prism. The circular portion shown around the back of the tip 18 of the female shaft rectangular prism is the female shaft intermediate position extension portion 14. The vertically elongated rectangles shown above and below the female shaft intermediate position extension 14 are the male shaft rods 12. It passes through the slide swing space 20 provided in the intermediate position extension portion 14 of the female shaft rod 13, The male shaft rod 12 is a single cylindrical rod with a spherical projection at its central position to prevent it from falling out of the sliding and oscillating space 20. It is rotatable within the sliding and oscillating space 20, with the spherical projection 21 as its central point. 【0023】 Figure 2 is a front view of Figure 1. The central filled circle represents the tip 17 of the male shaft 12, The elliptical portion shown around the tip 17 of the male shaft rod is the female shaft intermediate position extension 14. The horizontally elongated rectangular portion centered on the male shaft rod 12 is the through-hole portion of the sliding swing space 20 of the female shaft intermediate position extension part 14. The vertically elongated rectangles shown above and below the female shaft intermediate position extension portion 14 are the rectangular prism portion 16 of the female shaft rod 13. 【0024】 Figure 3 is a perspective view of Figures 1 and 2. The circular portion in the center is the female shaft intermediate position extension portion 14, and the rectangular prism-shaped portion that penetrates the female shaft intermediate position extension portion 14 from a slightly lower left to a higher right is the female shaft rectangular prism portion 16, which is integrally fixed to the female shaft intermediate position extension portion 14. The sliding swing space 20 of the intermediate position extension part 14 of the female shaft The diagram shows that the cylindrical portion 15 of the male shaft rod 12 penetrates the slide swing space 20, which has an opening that is a through hole, from slightly above the left to below the right. 【0025】 Figure 4 is a perspective view of the male shaft 12, showing that the shaft is a single-piece cylindrical male shaft with a spherical protruding retaining part 21 integrally fixed to the middle of the cylindrical part 15 on the longitudinal side, which serves as the center of rotation for the cross axis. The filled oval at the lower left tip indicates the tip 17 of the male shaft rod cylinder. 【0026】 Figure 5 is a front view of a bifurcated joint yoke 28, also known as a conventional bifurcated fitting. The joint portion 63, which connects the rectangular prism portion on the female shaft rod 13 side of the cross shaft in Figures 1 to 4 in a way that prevents rotation, is represented by two dashed lines on the ends of the left and right bifurcated metal fitting portions 61. A power transmission shaft mounting cylinder portion 38 is provided at the joint yoke base portion 30, which is the lower part of the bifurcated fitting portion 61. 【0027】 Figure 6 is a side view of Figure 5, showing that the joint opening 64 of the joint portion 63 at the tip is rectangular. Figure 7 is a plan view of Figure 5, and the horizontal rectangle in the center represents the joint yoke base 30 and bifurcated fitting portion 61 of the bifurcated fitting type joint yoke 28, with screw holes 67 for fixing the female shaft 13 to the tip of each bifurcated fitting portion 61. Behind the joint yoke base 30 is a cylindrical power transmission shaft mounting cylinder portion 38. 【0028】 Figure 8 is a bottom view of Figure 5, where the circular area indicated by the double circle in the center is the power transmission shaft mounting cylinder 38, and the joint yoke base 30 is shown behind it. Figure 9 is a side view of a bifurcated joint yoke 28 similar to that in Figure 6. However, the joint portion 63 at the tip of the bifurcated portion 61 is circular in shape to connect the cylindrical male shaft portion 15 of the male shaft 12 to it in a rotatable manner. A bearing is also provided to further smooth the rotation, and a joint portion 65 for supporting the rotation of the male shaft 12 is provided to hold it. 【0029】 Figure 10 shows the cross shafts 10 from Figures 1 to 4 connected by the conventional one-piece bifurcated metal joint yoke 28 from Figures 5 to 9. The diagonally oriented bifurcated metal fitting joint yoke 28 on the left side is equipped with a joint section 65 at its tip to support the rotation of the male shaft 12, The horizontally positioned bifurcated joint yoke 28 on the right is for use with the female shaft rod 13. In this embodiment diagram, the power transmission shafts 60 of the input shaft and output shaft are connected at a bending angle of approximately 30 degrees. In the diagram of this embodiment, an extracted diagram of the cross shaft 10, which is shown in the center of the diagram, is shown as an important part of the present invention, and the entire cross shaft 10 is shown in the lower circle, indicating the orientation of the female shaft rod 13 which is integrally fixed to the bifurcated metal fitting type joint yoke 28 in a manner that prevents relative rotation. The vertically oriented female shaft rod 13 has a rectangular prism portion 16 of the female shaft rod, It is connected to the right-side horizontal power transmission shaft 60 by a bifurcated metal fitting-type joint yoke 28, which is fixed in a non-rotatable manner with screws. 【0030】 The tip portion 17 of the cylindrical part 15 of the male shaft rod 12, which is in a horizontal position, This indicates that the two-pronged metal fitting type joint yoke 28, which is connected to the power transmission shaft 60 extending from the lower left, is rotatably connected to the circular male shaft rotation support joint part 65 at its tip. moreover, The overall view of the cross axis 10 shown within the circle in the partial extraction diagram at the tip of the downward-pointing dashed arrow indicates that The opening portion of the horizontally elongated rectangular slide swing space 20, which spreads outwards in a fan shape from near the center point of the female shaft intermediate position extension portion 14, is It is shown that the power transmission shaft 60 on the right side is horizontally elongated along the same horizontal line as the center line. At this point, the filled circle at the tip 17 of the cylindrical male shaft indicates that the male shaft 12, which is horizontally penetrating the female shaft 13, is located midway through the horizontally elongated rectangular opening of the slide swing space 20. 【0031】 Figure 11 is an embodiment diagram similar to Figure 10, and the orientation and position of the cross shaft 10 are extracted in the circle diagram, with the structure of the slide swing space 20 and the shape and inclination position of the male shaft 12 shown by dashed lines. The power transmission rotation shows the state after a quarter turn from Figure 10. The bifurcated metal fitting portion 61 of the bifurcated metal fitting type joint yoke 28 on the right side has changed from a vertical arrangement in the upper and lower parts of Figure 10 to a horizontal arrangement, and the square tip portion 18 of the female shaft rod 13 is visible. The bifurcated metal fitting portion 61 of the bifurcated metal fitting type joint yoke 28, which extends from the lower left, changes from a horizontal arrangement in Figure 10 to a vertical arrangement, and the male shaft rotation support joint portion 65, which holds both ends of the male shaft cylindrical portion 15 of the male shaft 12, is shown above and below. 【0032】 The overall view of the cross axis 10 shown within the circle in the partial extraction diagram at the tip of the downward-pointing dashed arrow indicates that The through-hole opening of the structure that extends outward from the sliding swing space 20 between the bent dashed lines on both sides near the center point of the female shaft intermediate position extension portion 14 of the female shaft rod 13, which is integrally fixed to the right-side bifurcated metal fitting type joint yoke 28 in a non-rotatable manner, is oriented vertically, This indicates that the male shaft 12 is sliding and tilting at an angle perpendicular to the centerline of the left power transmission shaft 60. 【0033】 A spherical retaining part 21 is shown by a dashed line in the middle of the cylindrical male shaft rod 12. The circular dashed line immediately outside the dashed line indicating the retaining portion 21 is a recess provided within the slide swing space 20 for housing the retaining portion 21. Within the slide oscillation space 20 including the recess, the male shaft 12 performs high-speed movement in which it tilts twice for each rotation of power transmission. To ensure smooth tilting and oscillation through smooth rotation of the male shaft 12 within the sliding oscillation space 20, the left-side bifurcated metal fitting type joint yoke 28, which connects and holds the male shaft 12, is equipped with a bearing to assist rotation in the joint portion 65 for supporting the rotation of the male shaft. 【0034】 Figure 12 is an embodiment diagram similar to Figure 10, Without providing the bifurcated fitting portion 61 of the bifurcated fitting type joint yoke 28 that was connected to the power transmission shaft 60 on the upper right side, and the female shaft square prism portion 16 of the female shaft 13 of the cross shaft 10, In this figure, the female shaft 13 is provided with a female shaft extension type connecting part 74, which houses and connects the male shaft 12, and the connecting part fixing base 76 and the power transmission shaft mounting cylinder 38, which is part of the connecting part fixing base 76, are integrally fixed to the power transmission shaft 60 so as not to rotate relative to each other, at the same position as in Figure 10. 【0035】 The diagonally oriented bifurcated metal fitting type joint yoke 28 and male shaft rod 12 on the left side have the same configuration as in Figure 10. The rotational and sliding movements of the male shaft 12 within the slide swing space 75, which houses and holds the male shaft 12 for rotational power transmission of the power transmission shaft 60 so that it can rotate and slide freely, are the same as in Figure 10. Furthermore, in the front view showing only the female shaft extension type connecting part 74, which is partially shown in the central part as in Figure 10, and is indicated within the circle of the partial extraction diagram at the tip of the downward-pointing dashed arrow, The rectangular opening of the slide oscillation space 75 is shown to be horizontally elongated on the center line of the power transmission shaft 60 to which the right-side connecting part fixing base 76 is connected. The dashed lines above and below the opening indicate the shape of the wall surface within the sliding and oscillating space 75 of the recess that matches the spherical shape of the spherical retaining part 21 provided at the intermediate position of the male shaft rod 12. 【0036】 Figure 13 is similar to Figure 12, but it is an embodiment that shows the connection state of the male shaft 12 and the female shaft extension type connecting part 74 after a quarter rotation from the state position in Figure 12 due to the rotation of power transmission. The plan view shows the state in which the male shaft connector 70, consisting of the female shaft extension type connector 74, the right-side connector fixing base 76, and the power transmission shaft mounting cylinder 38, is connected to the right-side power transmission shaft 60. The configuration of the slide swing space 75 within the female shaft extension type connecting part 74 is shown by a dashed line. The opening is through the upper and lower sides between the folded dashed lines shown on both sides of the inside, and in the center, there is a recess that matches the spherical shape of the spherical retaining part 21 located at the midpoint of the male shaft rod 12, indicated by a round dashed line. This shows that the central portion of the male shaft rod 12, which is joined to the bifurcated joint yoke 28 connected to the power transmission shaft 60 on the left side, is housed in the sliding swing space 75 of the female shaft rod extension type connecting part 74 and is tilted by sliding movement of about 30 degrees. 【0037】 Figures 14 to 16 show the joint yoke according to the method of Japanese Patent No. 7353611 and Japanese Patent Application No. 2025-034140. Japanese Patent No. 7353611 describes a four-way bending joint yoke 29 connected to a power transmission shaft 60, in which the joint portion 63 at the tip of the joint yoke 29 is capable of bending in four cross directions. Conventionally, in order to connect the power transmission shafts 60 of the input shaft and output shaft at a bending angle, a cross shaft of a cardan joint was mainly used to connect them at bending angles up to about 30 degrees, In the method of Patent No. 7353611, in addition to the cross-axis universal joint, it is possible to connect at an even greater bending angle by the bending action of the four-way bending joint yoke 29 itself. 【0038】 That four-way refraction is, The connecting portion 40, which is connected to the joint yoke base 30 by the connecting portion rotation pivot pin 39, rotates like a seesaw around the connecting portion rotation pivot pin 39 as a pivot point, causing bending in two directions. This results in a total of four directions of bending, including the bending in two directions of the hinge operating part 50, which is connected to the hinge shaft part 46 provided on the connecting part 40 so as to be able to rotate the hinge. Furthermore, Figures 14 to 16 show the configuration of the aforementioned Japanese Patent Application No. 2025-034140, characterized in that the projection of the hinge operating part overbending prevention projection 35, which prevents overbending of the hinge operating part 50 in the two-way bending portion of the four-way bending joint yoke 29, is installed on one of the parts of the four-way bending joint yoke 29. The joint yoke base 30 portion of one of the installation positions is modified in some way and installed, and a hinge bending prevention wall surface 36 for the hinge operating part 50 is newly provided to optimize the timing of the hinge operation. 【0039】 Figure 14 is a front view, where the cylindrical power transmission shaft mounting section 38 at the bottom is represented by a rectangle. The upper, wide, wing-shaped portion of the power transmission shaft mounting cylinder 38 is the joint yoke base 30. The contour and structure of the joint yoke base 30 are as follows: The lower part, including the bottom, is widened to more than four times the width of the power transmission shaft mounting cylinder 38 on both sides. From the wider lower section upwards, the width narrows as it moves towards the center, before reaching the two square-shaped hinge mechanism over-bending prevention protrusions 35, after which the top becomes horizontal. A small circular connecting pivot pin 39 is provided at the upper middle of the two square-shaped hinge operating part excessive bending prevention projections 35. The widened portion of the joint yoke base 30 is divided into three equal parts by two vertical dashed lines, and the wing-like portions on the left and right are hinge operating parts, hinge bending prevention wall surfaces 36, with a hinge bending 0-degree maintenance area 37 provided on the inside. 【0040】 The dashed horizontal line on the lower side of the joint yoke base 30 indicates the joint yoke base bottom surface 31, which is the bottom surface of the yoke base swing space 32. The two vertical dashed lines near the center indicate that the thickness of the yoke base swing space wall components 33, which constitute the yoke base swing space 32 provided within the joint yoke base 30, is different. The central part has a thickness that matches the thickness of the connecting section 40. The wing-like parts at both ends are sized to match the thickness of the hinge mechanism 50. This shows the difference in thickness between the two parts housed within the yoke base swing space 32, resulting in a step difference. The upper semicircular dashed line indicates a hidden portion of the semicircular connecting part 40, which rotates around the connecting part pivot pin 39 as its center point within the yoke base swing space 32, allowing for seesaw-like swinging motion. This portion is housed within the swing space 32 of the joint yoke base. The remaining exposed portion of the connecting part 40 is shown on the upper side of the joint yoke base 30. 【0041】 Furthermore, the diagram shows that hinge shaft portions 46, which are integrally fixed with the connecting portion 40, exist continuously in the lateral direction along solid lines, two dashed lines, and even small rectangles on either side of the dashed lines. The hinge operating part 50, which houses and connects the portions indicated by dashed lines on both sides of the hinge shaft portion 41, allowing the hinge to rotate freely from the hinge shaft portion 41, is shown extending from both sides upward. At the very top of the hinge operating parts 50 on both sides, which extend upward, there are two dashed lines indicating joint parts 63 that connect to the cross shaft 10. The hinge operating section intermediate column 51, which connects the vertically elongated sections on both sides where the joint portion 63 of the hinge operating section 50 is provided and fixes them together as the hinge operating section 50, is shown horizontally in the center. 【0042】 Figure 15 is a plan view of Figure 14, where the horizontal rectangle in the center is the hinge operating section 50, and the intermediate column 51 of the hinge operating section 50. The rectangles on both sides of the intermediate column 51 of the hinge operating part are joint parts 63 that form the ends of the hinge operating part 50, and the two dashed lines of the joint part 63 indicate holes for housing the shaft of the cross shaft 10, and a round hole for fixing the shaft, the screw hole 67, is shown in the center. The small squares protruding from both sides of the joint portion 63 indicate that a part of the hinge shaft portion 41 is visible. The joint yoke base 30 is shown above and below the horizontally elongated hinge operating part 50 in the center. The two vertical dashed lines in the middle of the upper and lower joint yoke bases 30 indicate the areas where the connecting pivot pin 39 is provided. The horizontally elongated rectangles above and below the joint portion 63, which is provided with the connecting pivot pin 39, are the yoke base swing space wall surface components 33. On the inside between the upper yoke base swing space wall component 33 and the lower yoke base swing space wall component 33, a hinge bending 0-degree maintenance area 37 of the joint yoke base swing space 32 is shown. 【0043】 Furthermore, the small squares at the corners that extend to both lateral ends of the upper and lower yoke base swing space wall component 33 are the hinge operation part excessive bending prevention parts 35, which are two small square-shaped protrusions as shown in Figure 14. The protruding portion of the hinge operating part excessive bending prevention portion 35 contacts the hinge operating part intermediate column portion 51 when the hinge operating part 50 is bent by about 30 degrees, thereby preventing excessive bending. 【0044】 The rectangular-shaped portions extending diagonally inward and tapering from the yoke base swing space wall component 33 shown above and below are hinge bending prevention wall components 36. The inside of the hinge bending prevention wall portion 36 shown above and below is the hinge bending 0 degree maintenance area 37. When the connecting part 40 is tilted by a seesaw motion, rotating with the connecting part rotation pivot pin 39 as the pivot point, The lower part of one inclined end of the hinge operating part 50, which is rotatably connected to the hinge shaft part 46 of the connecting part 40, fits into the hinge bending 0 degree maintenance area 37 between the hinge bending prevention wall surfaces 36 of the hinge operating part, which are shown on both sides, upper and lower. When the inclination of the connecting section 40 due to its seesaw motion is 30 degrees or more, the bending of the aforementioned fitted hinge operating section 50 due to its hinge motion is set to 0 degrees. The hinge operating part excessive bending prevention projection 35, the yoke base swing space wall component 33, and the hinge bending prevention wall component 36 all constitute a single, integrated joint yoke base 30. 【0045】 Figure 16 is a side view of Figure 14, where the bottom rectangle is the power transmission shaft mounting cylinder 38. The upper part is the joint yoke base 30, and within the inner yoke base swing space 32, the connecting part 40 is represented as a vertically elongated rectangle. The hinge mechanism 50 is shown vertically at its upper part. The filled circle below the hinge operating part 50 represents the hinge shaft 41, the two diagonal lines above it indicate that the intermediate column 51 of the hinge operating part is on the opposite side, and the upper tip represents the joint 63. 【0046】 The joint portion 63 has a joint portion opening hole 64 which is a square opening, When the hinge operating part 50 bends approximately 30 degrees to the left or right from the connecting part 40, the hinge operating part intermediate column 51 comes into contact with the sharp-angled, slanted hinge operating part overbending prevention projections 35 at the upper left and right ends of the lower joint yoke base 30, thereby preventing excessive bending. Furthermore, when the hinge operating part 50 is tilted forward or backward by about 30 degrees together with the connecting part 40, the lower part of the hinge operating part 50 fits into the hinge bending 0-degree maintenance area 37, which is the width of the space inside the hinge bending prevention wall surface 36 of the joint yoke base 30, which is provided in a series from the left and right acute-angled parts downwards, and the width of the space inside the lower part of the hinge operating part 50 is about the same as the width of the hinge operating part 50, thereby setting the bending of the hinge operating part 50 to 0 degrees. 【0047】 Figure 17 is a front view of the male shaft 12, Instead of a single-piece male shaft 12, which is rotatably connected to the joint portion 63 of the four-way bending joint yoke 29 and has a spherical retaining portion 21 in the middle of the cylindrical male shaft portion 15 shown in the perspective view of Figure 4, The spherical retaining portion 21 has a male shaft bearing mounting portion 22 in the portion of the male shaft cylindrical portion 15 that is housed in the female shaft swing space 20 on both sides, and the tip of the male shaft bearing mounting portion 22 is made into a square prism male shaft tip portion 23, similar to the female shaft 13 of the present invention, so that it can be connected to the joint portion 63 of the four-way bending joint yoke 29 in a non-rotatable fixed state, thereby integrally fixing the power transmission shaft 60 and the four-way bending joint yoke 29 on the connecting side. In order for the male shaft 12 and female shaft 13 to be fixed together with the four-way bending joint yoke 29, a bearing for rotational support is provided on the male shaft 12 to ensure that the smooth sliding movement of the male shaft 12 within the important sliding oscillation space 20 is not hindered. 【0048】 Figure 18 shows an embodiment of a universal joint consisting of a four-way bending joint yoke 29 (Figures 14 to 16), a cross shaft 10 (female shaft 13, Figures 1 to 3, and male shaft 12, Figure 17), This diagram shows the connection state in which rotational power is transmitted between the input shaft and the output shaft power transmission shaft 60 using a universal joint consisting of a four-way bending joint yoke 29 at the upper right, a cross-shaft 10 composed of a male shaft 12 and a female shaft 13 in the middle position, and a four-way bending joint yoke 29 at the lower position. This is an example diagram showing that the joint portions 63 of the upper and lower four-way bending joint yoke 29 and the male shaft rod 12 of the cross-axis 10 are each tilted at an angle of 30 degrees, resulting in an overall right-angle bending angle of 90 degrees. 【0049】 In this example diagram of Figure 18, the tip 19 of the male shaft 12, which is housed in a slidable and rotatable manner within the female shaft swing space 20 of the female shaft 13 of the cross shaft 10, which is fixedly and immobilely connected to the joint portion 63 of the four-way bending joint yoke 29 connected to the lower power transmission shaft 60, is represented by a filled rectangle. The filled-in rectangle is inclined at approximately 30 degrees along with the joint 63 of the hinge operating part 50 of the four-way bending joint yoke 29 on the upper right side, which is fixed and non-rotatable. The male shaft rod 12, which has a single linear structure, is tilted at approximately 30 degrees within the female shaft rod swing space 20, indicating that it is in a horizontal position at the midpoint of the slanted opening. 【0050】 Furthermore, the lower right side of the hinge operating part 50 at the right end of the connecting part of the four-way bending joint yoke 29 on the lower left, which is inclined at a 30-degree angle, is housed within the hinge bending 0-degree maintenance area 37 between the hinge bending prevention wall surfaces 36 of the hinge operating part, indicating a state where there is no hinge bending. The hinge mechanism 50 of the horizontally positioned four-way bending joint yoke 29 on the upper right is tilted at a 30-degree angle and contacts the triangular pyramidal portion of the excessive bending prevention projection 35 of the hinge mechanism, thereby preventing further excessive bending. 【0051】 Figure 19 is an embodiment diagram similar to Figure 18, The power transmission shaft 60 shows the state after a quarter rotation from Figure 18. In Figure 18, the cross axis 10 represents the front side as shown in Figure 2, whereas in Figure 19, after a quarter rotation, it represents the planar side as shown in Figure 1. The inner part of the circular female shaft intermediate position extension 14 of the cross axis 10 is represented by a dashed line. The sliding pivot space 20 within the female shaft intermediate position extension section 14 has a thickness and width that matches the shape of the male shaft rod 12. Furthermore, the space structure includes recesses that match the two male shaft bearing mounting portions 22 provided on the male shaft 12 in Figure 17, thereby ensuring smooth sliding movement and rotation. A quarter-turn rotation from Figure 18 results in a composition where the orientation of the four-way bending joint yoke 29 joined to the female shaft rod 13 on the lower left and the four-way bending joint yoke 29 joined to the male shaft rod 12 on the upper right are swapped. 【0052】 Figure 20 is an embodiment diagram similar to Figure 18, The joint portion 63 of the hinge operating portion 50 of the four-way bending joint yoke 29, which is connected to the power transmission shaft 60 on the lower left side, has been removed from the intermediate column portion 51 of the hinge operating portion on both sides, including the joint portion 63, and the square column portion 16 of the female shaft rod 13 has been removed. A female shaft rod extension type connecting part 74, which has the same configuration as the female shaft intermediate position extension part 14, is attached to the intermediate column part 51 of the hinge operating part, which is on the center line of the power transmission rotation to which the rotational power is transmitted, at an intermediate position of the hinge operating part intermediate column part 51, and is oriented in the direction of the four-way bending joint yoke 29 that connects to the mating power transmission shaft 60 on the upper right side, as in Figure 18, and is integrally fixed to the hinge operating part intermediate column part 51 with a connecting part fixing base 76. 【0053】 The female shaft extension type connecting part 74 is similar in shape and structure to the female shaft intermediate position extension part 14 in Figure 18. The configuration is the same as in Figure 18, except that the female shaft rod 13 has a rectangular prism portion 16, the joint portions 63 on both sides that were joined to the female shaft rod rectangular prism portion 16, and the hinge operating portion 50 from the intermediate column portion 51 to the tip are not provided. The female shaft extension type connecting part 74, along with the hinge operating part 50 which is fixed integrally as in Figure 18, is shown in a front view inclined at approximately 30 degrees. 【0054】 Figure 21 is an embodiment diagram similar to Figure 19, but The power transmission shaft 60 shows the state after a quarter rotation from Figure 20. In Figure 20, the female shaft extension type connecting part 74 is shown on the front side, whereas in Figure 21, it is shown on the planar side. The inner part of the circular outer shape of the female shaft extension type connecting part 74 is represented by a dashed line. The slide oscillation space 75 is an internal space structure that conforms to the shape of the male shaft 12, and is designed to ensure smooth sliding, rotation, and holding of the male shaft 12. Figures 21 and 19 show that the position, installation direction, and jointed connection state of the female shaft extension type connecting part 74 with the male shaft 12 remain unchanged. [Industrial applicability] 【0055】 A cross-shaped universal joint is a cross-shaped universal joint in which the two shafts, a male shaft 12 and a female shaft 13 that are perpendicular to each other in a cross shape, can each swing independently, thereby suppressing the occurrence of uneven velocity motion. Furthermore, the female shaft 13 is integrally fixed with the power transmission shaft 60, preventing relative rotation, and allowing power transmission to rotate integrally with the power transmission shaft 60. By fixing them as a single unit, the orientation of the opening of the slide swing space 25 provided in the intermediate position extension portion 14 of the female shaft rod 13 is fixed to the optimal position. The rotation and sliding movement of the male shaft 12, which is partially housed within the slide oscillation space 25, will become smoother. 【0056】 The reason why this power transmission shaft 60 can be fixed integrally with the male shaft 12 is that the male shaft 12 is capable of rotation and sliding movement in the sliding oscillation space 25. Based on this principle, By making it possible to create a female shaft extension type connecting part 74 for a male shaft, consisting only of the shape and structure of the female shaft intermediate position extension part 14 provided within the slide swing space 25 without providing the shaft portion of the female shaft 13, a simple configuration integrated with the power transmission shaft 60 can be achieved. This enables more stable transmission of rotational power, contributing to industrial development. [Explanation of Symbols] 【0057】 10. Cross shaft (a cross shaft consisting of a male shaft and a female shaft) 12 Male shaft 13 Female shaft 14. Female shaft intermediate position extension 20. Slide swing space (a space within the extension section of the female shaft that allows for free sliding) 28. Two-pronged metal fitting type joint yoke (conventional general type) 29. Four-way bending joint yoke (Patent No. 7353611 method) 30 Joint yoke base 38 Power transmission shaft mounting cylinder section (part of the joint yoke base and connecting section fixing base) 40. Connecting section (rotatably swingable from the yoke base) 41 Hinge shaft 50. Hinge operating part (a bifurcated part that can swing freely via hinge operation from the connecting part) 70. Connector for male shaft (connector consisting of a female shaft extension type connector and a connector fixing base) 74. Female shaft extension type connecting section (connects by housing and holding the male shaft so that it can rotate and swing freely) 75. Slide swing space (a space within the female shaft extension type connecting section that allows for free sliding)

Claims

[Claim 1] In a universal joint where the axial direction of the input shaft and the axial direction of the output shaft of a power transmission shaft are not parallel, but rather inclined, and rotational power can be transmitted by joining them at the angle formed by these axes, The cross shaft of a cross-shaped universal joint has two shafts arranged in a cross shape. The two shafts arranged in a cross shape vertically and horizontally on the cross axis are not fixed together, and the cross axis is made up of individual two shafts. One of the separate shafts is attached to the male shaft. The other shaft is used as the female shaft, The male shaft having a single linear structure The male shaft is provided with a retaining portion that prevents separation from the female shaft by having one or more parts of the linear structure protrude from one intermediate position that serves as the center point of power transmission rotation as the cross shaft, The central portion of the female shaft, centered on the intermediate position which is the center point, is expanded in a disc-like or spherical shape on the circumference perpendicular to the center line of the female shaft, The space is provided as a swing space for housing the intermediate portion of the male shaft, extending from the central point on the inside of the expansion portion to the outside of the circumference which is the end of the expansion portion in the orthogonal direction. A universal joint consisting of a cross shaft was designed to house the male shaft rod within the swing space so that it could rotate and slide freely through the swing space. The female shaft and the bifurcated fitting portion of the joint yoke on the power transmission shaft side, which is joined and connected to the female shaft, are fixed together, and the expanded portion is positioned on the center line of the power transmission rotation of the joint yoke so that it cannot rotate relative to it. The intermediate portion of the male shaft is housed in the swing space so that it can rotate and slide freely, allowing for connection. A universal joint characterized by the following features.

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