Patent Description:
This application relates to the field of terminal technologies, and in particular to, a cam assembly, a folding mechanism, a terminal device, and a method for manufacturing a cam assembly.

With the rapid development of terminal devices such as smartphones, users have an increasingly urgent demand for large-size screens of the smartphones. However, the larger the screen size, the larger the smartphone size. Therefore, to minimize the smartphone size on the basis of the large-size screen, foldable smartphones have emerged. During folding or unfolding the foldable smartphone, a cam, as an extremely important part of the foldable smartphone, inevitably frequently generates relatively friction with other components in the foldable smartphone. Therefore, the cam needs to have high wear resistance.

In the related technology, a cam is made of stainless steel, and a wear-resistant layer is usually disposed on an outer surface of the cam. However, during use, the foldable smartphone needs to be folded or unfolded frequently. Therefore, friction frequently occurs between the cam and the other components. Because the wear-resistant layer is usually small in thickness, when the wear-resistant layer is completely worn, a stainless steel body of the cam is worn gradually, that is, the cam no longer has relatively high wear resistance.

How to ensure that the overall wear resistance of the cam is further increased while meeting a strength requirement of the cam is a technical problem that needs to be resolved urgently at present. <CIT> relates to a hinge device of a dual-shaft construction that performs a synchronized pivoting motion, and t an undulating pivoting motion; and an electronic device using the hinge device. In the hinge device, a second member is connected to a first member so that the second member can perform an undulating pivoting motion from a state in which the first member and second member are overlapped, wherein the hinge device is constructed so that first and second pivot shaft parts are disposed in parallel on a hinge base disposed between the end part of the first member and the end part of the second member; the hinge base is provided so as to be free to perform an undulating pivoting motion with respect to the first member via the first pivot shaft part; the second member is disposed so as to be free to perform an undulating pivoting motion with respect to the hinge base via the second pivot shaft part; a first pivoting part and second pivoting part that pivot in a relative manner when performing an undulating pivoting motion are respectively disposed on the first pivot shaft part and second pivot shaft part; and the first pivoting part and second pivoting part are connected by a connecting link part, so that the second pivoting part is caused to perform a transmitted co-pivoting motion by this first pivoting part.

<CIT> relates to a dual-shaft synchronous motion device, comprising a first shaft driving a first rotor synchronously and a second shaft driving a second rotor synchronously, the first rotor and the second rotor respectively having a cylindrical main body; and a tractive member connected between the first rotor and the second rotor, the first rotor and the second rotor being turned synchronously.

To resolve the foregoing technical problems, this application provides a cam assembly, a folding mechanism, a terminal device, and a method for manufacturing a cam assembly, which can improve wear resistance of the cam assembly while ensuring relatively high strength of the cam assembly.

This application provides a cam assembly, applied to a folding mechanism. The folding mechanism includes a cam structure. The cam assembly includes a cam body and a frame. The cam body includes a first cam and a second cam that are oppositely disposed, and a connection body located between the first cam and the second cam; materials of the first cam and the second cam include a wear-resistant material; and a first concave portion cooperating with the cam structure is disposed at one end of the cam body. The frame includes a first fastener and a second fastener that are oppositely disposed, and a connector located between the first fastener and the second fastener; the first fastener is embedded into the first cam, and the second fastener is embedded into the second cam; extension directions of the first fastener in the first cam include at least the axial direction and the circumferential direction, and extension directions of the second fastener in the second cam include at least the axial direction and the circumferential direction; and the connector is embedded into the connection body.

The materials of the cam in this application include the wear-resistant material, so that the overall wear resistance of the cam assembly is relatively high. The first fastener is embedded into the first cam, the second fastener is embedded into the second cam, and the extension directions of each of the first fastener and the second fastener include at least the axial direction and the circumferential direction, so that the first fastener and the second fastener can provide relatively good axial and circumferential support for the first cam and the second cam each, thereby improving strength of the first cam and the second cam. The connector is embedded into the connection body, and therefore the connector can provide relatively good support for the connection body, thereby improving the strength of the connection body. In conclusion, the overall strength of the cam assembly can be improved by using the frame in the cam assembly of this application, and the overall wear resistance of the cam assembly can be improved by using the cam containing the wear-resistant material.

In some feasible implementations, the first fastener and the second fastener each include a first fastening body and a second fastening body located on the first fastening body, the first fastening body extends in the circumferential direction, and the second fastening body extends in the axial direction. Therefore, the first fastening bodies can bear a radial force, that is, can provide radial support for the first cam and the second cam. The second fastening bodies can bear an axial force, that is, can provide axial support for the first cam and the second cam. The connector can bear a transverse force between the first cam and the second cam, that is, can provide transverse support for the cam body.

In some feasible implementations, there are a plurality of first concave portions, and a convex portion is formed between every two first concave portions; and there are a plurality of second fastening bodies, the second fastening bodies are in a one-to-one correspondence with the convex portions, and a part of the second fastening body is located in the convex portion. When the cam assembly is applied to a terminal device, the first concave portion interacts with the cam structure. Therefore, when there are a plurality of first concave portions, the plurality of concave portions can jointly bear a force exerted by the cam structure. In addition, when the second fastening bodies are in a one-to-one correspondence with the convex portions, and a part of the second fastening body is located in the convex portion, each second fastening body can provide support for the convex portion, and therefore the strength of the cam assembly can be further improved.

In some feasible implementations, the first fastening body includes a plurality of fastening portions arranged in a preset shape, and one second fastening body is fastened between every two fastening portions. The preset shape may include a circle, square, or the like. In this way, the fastener may be formed by welding the plurality of fastening portions and second fastening bodies.

In some feasible implementations, the first fastening body is of an integrally formed structure. In this way, the first fastening body may be obtained by bending a steel plate or round steel, so that strength of the first fastening body is relatively high, and therefore the strength of the cam assembly can be improved.

In some feasible implementations, end faces of the first fastening body are closed. Because the structure with the closed shape has higher strength, the strength of the first fastening body can be further improved by using such structure, and therefore the strength of the cam assembly can be improved.

In some feasible implementations, the second fastening body includes a first fastening column and a second fastening column that are respectively fastened on two sides of the first fastening body. In this way, the center of the first fastening column and the center of the second fastening column may coincide with the center of the first fastening body. When the first fastening column bears a force, the force can be transferred to the first fastening body and the second fastening column, and therefore the first fastening body can provide support well.

In some feasible implementations, the second fastening body is of an integrated structure. In this way, the second fastening body may be obtained by cutting a steel plate or round steel, which can improve the strength of the second fastening body, and therefore the strength of the cam assembly can be improved.

In some feasible implementations, the second fastening body is fastened on the outer side or inner side of the first fastening body. In this way, both the first fastening body and the second fastening body can be of an integrated structure, and therefore the strength of the entire cam assembly can be improved.

In some feasible implementations, a shape of a first section captured along a first cutting plane of the first fastening body includes a circle or a polygon, and the first cutting plane is perpendicular to the circumferential direction. In this way, the first fastening body can be manufactured by using steel with the existing section shape, that is, material can be easily obtained.

In some feasible implementations, the shape of the first section includes a rectangle, and long sides of the first section extend in the axial direction. When the cam assembly is applied to a terminal device, the first concave portion bears a force exerted by the cam structure. Because a first abutting surface of the first concave portion is usually an inclined plane having an obtuse angle with an end face of the first cam, an included angle between the force and the end face of the first cam is an obtuse angle, and the force can be decomposed into a force in the axial direction of the first cam (namely, axial force) and a force in the radial direction of the first cam (namely, radial force). When long sides of a cross-section of the first fastening body extend in the axial direction of the first cam, the extension direction of the long sides of the first fastening body is the same as the direction of the axial force, and therefore the first fastening body can provide better axial support for the first cam. Similarly, the first fastening body can also provide better axial support for the second cam.

In some feasible implementations, a shape of a second section captured along a second cutting plane of the second fastening body includes a circle or a polygon, and the second cutting plane is perpendicular to the axial direction. In this way, the second fastening body can be manufactured by using steel with the existing section shape, that is, materials can be easily obtained.

In some feasible implementations, the shape of the second section includes a rectangle, and long sides of the second section extend in the radial direction of the first cam or the second cam. When the cam assembly is applied to a terminal device and bears a force exerted by the cam structure, the extension direction of long sides of a cross-section of the second fastening body is the same as the direction of the radial force formed by decomposition of the force, and therefore the second fastening body can provide better radial support for the first cam and the second cam.

In some feasible implementations, materials of the connection body include a wear-resistant material. In this way, the materials of the connection body, the first cam, and the second cam are the same, so that the connection body, the first cam, and the second cam can be manufactured in an integral forming manner, which can avoid the situation that welds are generated between the connection body, the first cam and the second cam when manufacturing a cam body, and therefore cracks appear at the welds when the cam body bears a force.

In some feasible implementations, materials of both the first cam and the second cam include a ceramic particle reinforced aluminum matrix composite. Because the ceramic particle reinforced aluminum matrix composite has relative high wear resistance, the first cam and the second cam have relative high wear resistance.

In some feasible implementations, materials of the frame include stainless steel. Stainless steel is high strength steel, and therefore the strength of the frame can be improved, thereby improving the strength of the cam assembly.

This application further provides a folding mechanism, including a cam assembly according to any of the foregoing implementations, and a cam structure cooperating with the cam assembly. The folding mechanism can achieve all effects of the foregoing cam assembly.

In some feasible implementations, the cam structure and the cam assembly are arranged in the axial direction. A second concave portion is disposed at the end that is of the cam structure and that faces the cam assembly. The second concave portion is configured to abut on the first concave portion of the cam assembly, so that when the cam structure rotates around an own axis, the cam assembly moves in the axial direction. When the cam assembly of this application is applied to a terminal device, the cam assembly always has relatively high wear resistance, so that there will be no large amount of wear, and therefore the folding mechanism can provide relatively stable damping. When the terminal device is folded or unfolded to an angle, the folding angle will not be increased or decreased due to an accidental touch of a user, and therefore user experience can be improved.

In some feasible implementations, the folding mechanism further includes a spring and a rotating shaft. The cam structure is fastened on the outer surface of the rotating shaft. The cam assembly is slidably connected to the outer surface of the rotating shaft. The spring is sleeved on the rotating shaft and is located on a side that is of the cam assembly and that is away from the cam structure, the end that is of the spring and that is away from the cam assembly remains in the same position relative to the rotating shaft, the other end of the spring abuts on the cam, and the spring is compressed when the cam assembly moves. In this way, when the cam structure rotates, a force can be exerted on the first concave portion by the second concave portion, and the cam assembly moves towards the spring and compresses the spring while bearing the force. When the cam structure stops rotating, the force exerted on the cam assembly by the cam structure can be balanced with an elastic force of the spring, and therefore the implementation process of such structure is relatively simple.

This application further provides a terminal device, including a folding mechanism according to any of the foregoing implementations. The terminal device can achieve all effects of the folding mechanism.

This application further provides a method for manufacturing a cam assembly, used to manufacture the cam assembly according to any of the foregoing implementations. The manufacturing method includes: manufacturing a frame; placing the frame into a prefabricated mold; pouring a solution containing a wear-resistant material into the mold, and cooling to obtain a semifinished part of the cam assembly; performing die forging on the semifinished part of the cam assembly, to obtain a die forged cam assembly; performing heat treatment on the die forged cam assembly, to obtain a cam assembly after heat treatment; and surfacing the cam assembly after heat treatment, to obtain the cam assembly.

The frame is placed into the prefabricated mold at first, and then the solution containing the wear-resistant material is poured into the mold, so that a cam body and the frame are tightly attached, and therefore the strength of connection between the cam body and the frame can be improved. Die forging is performed on the semifinished part of the cam assembly, which can improve density of the cam assembly, and thus improve wear resistance of the cam assembly. Heat treatment is performed on the die forged cam assembly, which can improve comprehensive mechanical properties of the cam assembly. Surfacing is performed on the cam assembly after heat treatment, which can improve size accuracy and surface smoothness of the cam assembly.

To describe the technical solutions in embodiments of this application more clearly, the following briefly describes the accompanying drawings required for describing the embodiments of this application. Apparently, the accompanying drawings in the following descriptions merely show some embodiments of this application, and a person of ordinary skill in the art may still derive others drawings from these accompanying drawings without creative efforts.

Reference numerals: <NUM>-Folding assembly; <NUM>-Flexible screen; <NUM>-Housing; <NUM>-Folding mechanism; <NUM>-Rotating shaft; <NUM>-Spring; <NUM>-First cam structure; <NUM>-First cam portion; <NUM>-Second cam portion; <NUM>-First connection portion; <NUM>-First end face; <NUM>-First concave portion; <NUM>-First side surface; <NUM>-Second side surface; <NUM>-Second cam structure; <NUM>-Third cam portion; <NUM>-Second connection portion; <NUM>-Second end face; <NUM>-Second concave portion; <NUM>-Third side surface; <NUM>-Fourth side surface; <NUM>-Third cam structure; <NUM>-Cam end face; <NUM>-Cam assembly; <NUM>-Cam body; <NUM>-Cam; <NUM>-Third end face; <NUM>-Fourth end face; <NUM>-Third concave portion; <NUM>-Annular hole position; <NUM>-Longitudinalthrough hole; <NUM>-Abutting surface; <NUM>-Connection body; <NUM>-Fifth end face; <NUM>-Sixth end face; <NUM>-Transverse through hole; <NUM>-Frame; <NUM>-Fastener; <NUM>-arc-Shaped fastening body; <NUM>-First fastening column; <NUM>-Second fastening column; <NUM>-Fastening ring; <NUM>-Third fastening column; <NUM>-Joint; <NUM>-Connector.

The following clearly describes the technical solutions in embodiments of this application with reference to the accompanying drawings in embodiments of this application. Apparently, the described embodiments are merely some rather than all of embodiments of this application. Based on the embodiments of this application, all other embodiments obtained by a person of ordinary skill in the art without creative efforts fall within the protection scope of this application.

The term "and/or" in this specification describes only an association relationship for describing associated objects and represents that three relationships can exist. For example, "A and/or B" can represent the following three cases: Only A exists, both A and B exist, and only B exists.

In the specification and claims of this application, the terms "first", "second", "third", "fourth", and the like are intended to distinguish between different objects but do not indicate a particular order of the objects. For example, a first target object and a second target object are used to distinguish between different target objects, and are not used to describe a specific order of the target objects. In embodiments of this application, the word such as "as an example" or "for example" is used to represent giving an example, an illustration, or a description. In embodiments of this application, any embodiment or design solution described as "as an example" or "for example" shall not be explained as being preferred or advantageous over other embodiments or design solutions. To be precise, the use of the words such as "as an example" or "for example" is intended to present a related concept in a specific manner.

In the descriptions of the embodiments of this application, unless otherwise specified, "a plurality of" means two or more. For example, a plurality of processing units mean two or more processing units, and a plurality of systems mean two or more systems.

Embodiments of this application provide a cam assembly and a folding mechanism. The cam assembly and the folding mechanism can be applied to a foldable smartphone. In addition, the cam assembly and the folding mechanism can also be applied to a terminal device with a folding function, such as a foldable tablet computer, a foldable game console, a foldable personal digital assistant (personal digital assistant, PDA), which is not limited in the embodiments of this application.

<FIG> is a schematic diagram of a structure of a foldable smartphone in a semi-folded state according to an embodiment of this application. <FIG> is a schematic diagram of a structure of a foldable smartphone in an unfolded state according to an embodiment of this application. As shown in <FIG> and <FIG>, the foldable smartphone includes at least a folding assembly <NUM> and a flexible screen <NUM> fastened to one surface of the folding assembly <NUM>. The folding assembly <NUM> can be folded or unfolded to drive folding or unfolding of the flexible screen <NUM>. The foldable smartphone may be an inward foldable mobile phone, that is, the flexible screen <NUM> is located on the inner side of the folding assembly <NUM>. The foldable smartphone may also be an outward foldable mobile phone, that is, the flexible screen <NUM> is located on the outer side of the folding assembly <NUM>. If the foldable smartphone is an inward foldable mobile phone, when a folding angle of the folding assembly <NUM> is <NUM>, the flexible screen <NUM> is completely wrapped in the folding assembly <NUM>, which can not only reduce the size of the phone, but also protect the flexible screen <NUM>. When the folding assembly <NUM> is completely unfolded, that is, the angle of the folding assembly <NUM> is <NUM> degrees, the flexible screen <NUM> is in a flattened state and also in a state with maximum display area, and the user can operate on the flexible screen <NUM>.

As shown in <FIG>, the folding assembly <NUM> includes a housing <NUM> and a folding mechanism <NUM> connected to the housing <NUM>. There may be one folding mechanism <NUM>, and the folding mechanism <NUM> is in a middle position in the Y direction. In other embodiments, there may alternatively be two, three, or more folding mechanisms <NUM>. When there are a plurality of folding mechanisms <NUM>, the plurality of folding mechanisms <NUM> are evenly arranged in the Y direction.

As shown in <FIG>, the folding mechanism <NUM> includes two rotating shafts <NUM>, two first cam structures <NUM>, a second cam structure <NUM>, a third cam structure <NUM>, and two springs <NUM>. The two rotating shafts <NUM> are rotatably connected to the housing <NUM>, and the two rotating shafts <NUM> are disposed in the Y direction and parallel to each other. For the positions of the rotating shafts <NUM> on the foldable smartphone, refer to <FIG> and <FIG>.

It should be noted that the quantities of the first cam structure <NUM>, second cam structure <NUM>, third cam structure <NUM> and spring <NUM> shown in <FIG> are only used as an example and do not constitute a limitation on the technical solutions of the embodiments of this application. If the quantity of the first cam structures <NUM> is M, the quantity of the second cam structures <NUM> and the quantity of the third cam structures <NUM> are both N, and the quantity of the springs <NUM> is P, M and P are equal and are both twice of N. In other embodiments of this application, both M and P are <NUM>, and N is <NUM>; or both M and P are <NUM>, and N is <NUM> or the like.

As shown in <FIG>, the two first cam structures <NUM> are respectively connected to the two rotating shafts <NUM>. For example, one first cam structure <NUM> is connected to one rotating shaft <NUM>, the other first cam structure <NUM> is connected to the other rotating shaft <NUM>, and connection positions of the two first cam structures <NUM> on the rotating shafts <NUM> correspond to each other.

As shown in <FIG>, the first cam structure <NUM> includes a first cam portion <NUM>, a second cam portion <NUM>, and a first connection portion <NUM>, where the first connection portion <NUM> is connected between the first cam portion <NUM> and the second cam portion <NUM>. As shown in <FIG>, connection positions of the first cam portions <NUM> of the two first cam structures <NUM> on the rotating shafts <NUM> correspond to each other, and connection positions of the second cam portions <NUM> of the two first cam structures <NUM> on the rotating shafts <NUM> also correspond to each other. Still referring to <FIG>, the first cam portion <NUM> is fastened to the outer surface of the rotating shaft <NUM>, and the first cam portion <NUM> can rotate with rotation of the rotating shaft <NUM>. The first cam portion <NUM> is of a hollow structure with openings at two ends. As shown in <FIG>, a first concave portion <NUM> is formed on a first end face <NUM> of the first cam portion <NUM>. There may be three first concave portions <NUM>, and the three first concave portions <NUM> are evenly arranged along the circumference of the first cam portion <NUM>. In other embodiments of this application, there may be one, two, four, or more first concave portions <NUM>, which is not limited in the embodiments of this application.

As shown in <FIG>, the first concave portion <NUM> is provided with a first side surface <NUM> and a second side surface <NUM> opposite to the first side surface <NUM>, and both the first side surface <NUM> and the second side surface <NUM> are inclined planes. The first concave portion <NUM> has a small bottom and a large top.

As shown in <FIG>, the second cam portion <NUM> is fastened to the outer surface of the rotating shaft <NUM>, and the second cam portion <NUM> and the first cam portion <NUM> are arranged in the axial direction of the rotating shaft <NUM>. The structure of the second cam portion <NUM> may be different from the structure of the first cam portion <NUM>, specifically, two end faces of the second cam portion <NUM> are planes.

As shown in <FIG>, the second cam structure <NUM> includes two third cam portions <NUM> and a second connection portion <NUM> connected between the two third cam portions <NUM>. As shown in <FIG>, the two third cam portions <NUM> are respectively sleeved at corresponding positions of the two rotating shafts <NUM>, and the two third cam portions <NUM> can slide in the axial direction of the rotating shafts <NUM>. One third cam portion <NUM> of the two third cam portions <NUM> is sleeved on one rotating shaft <NUM>, and the other third cam portion <NUM> is sleeved on the other rotating shaft <NUM>.

As shown in <FIG>, the third cam portion <NUM> is of a hollow structure with openings at two ends, the third cam portion <NUM> is provided with a second end face <NUM>, and three second concave portions <NUM> are formed on the second end face <NUM>. As shown in <FIG>, the second end face <NUM> faces the first concave portion <NUM>. In other embodiments of this application, there may be one, two, four, or more second concave portions <NUM>, which is not limited in the embodiments of this application.

As shown in <FIG>, the second concave portion <NUM> is provided with a third side surface <NUM> and a fourth side surface <NUM> opposite to the third side surface <NUM>, both the third side surface <NUM> and the fourth side surface <NUM> are inclined planes, and the second concave portion <NUM> is in a shape with a small bottom and a large top. As shown in <FIG>, the third side surface <NUM> fits the first side surface <NUM>, and abuts on the same. That the third side surface <NUM> fits the first side surface <NUM> may mean that the third side surface <NUM> and the first side surface <NUM> have the same surface shape, for example, both the third side surface <NUM> and the first side surface <NUM> are planes, or both the third side surface <NUM> and the first side surface <NUM> are curved surfaces. Because the first cam portion <NUM> can rotate with an axis of the rotating shaft <NUM> as a center, and the third cam portion <NUM> can move in the axial direction of the rotating shaft <NUM>, when both the third side surface <NUM> and the first side surface <NUM> are curved surfaces, the first cam portion <NUM> can be rotated to any position, and the third side surface <NUM> abuts on the first side surface <NUM> as much as possible.

As shown in <FIG>, two cam end faces <NUM> of the third cam structure <NUM> are planes.

As shown in <FIG>, one spring <NUM> of the two springs <NUM> is sleeved on one rotating shaft <NUM> and located at an end that is of the second cam structure <NUM> and that is away from the first cam portion <NUM>, and the other spring <NUM> is sleeved on the other rotating shaft <NUM> and located at an end that is of the other second cam structure <NUM> and that is away from the second cam portion <NUM>. A first end of each spring <NUM> of the two springs <NUM> is in contact with the third cam portion <NUM>, and a second end of the same is fastened to the rotating shaft <NUM>.

As shown in <FIG>, when an included angle between the two opposite first cam structures <NUM> is <NUM>, the folding angle of the foldable smartphone is <NUM>, and the third cam portion <NUM> is in contact with the first end of the spring <NUM>. When a force is exerted on the folding assembly <NUM> to make the two first cam structures <NUM> to rotate with the rotating shaft <NUM>, the first side surface <NUM> of the first cam portion <NUM> generates an extrusion force on the third side surface <NUM> of the third cam portion <NUM>. Because the second cam structure <NUM> can slide in the axial direction of the rotating shaft <NUM>, the second cam structure <NUM> generates displacement under the action of the extrusion force, that is, moves towards a direction away from the first concave portion <NUM> on which the second cam structure abuts, to extrude the spring <NUM>. The spring <NUM> under pressure generates compressive deformation, to exert an elastic force on the second cam structure <NUM>. During the process of folding the foldable smartphone, the second cam structure <NUM> bears two forces all the time: one is the extrusion force exerted by the first cam structure <NUM>, and the other is the elastic force exerted by the spring <NUM>, the two forces have opposite directions, and therefore balance can be achieved. After the foldable smartphone is folded to an angle and stops, the two forces that achieve balance can ensure that the foldable smartphone stops at this angle, that is, the folding mechanism <NUM> can provide a damping force, to keep the foldable smartphone at this angle. It should be noted that, in this embodiment, a damping effect of the folding mechanism <NUM> can be achieved through interaction between the first cam portion <NUM> and the second cam structure <NUM>. To enable the folding mechanism <NUM> to have a better damping effect, in other embodiments, the structure of the second cam portion <NUM> may be the same as the structure of the first cam portion <NUM>, and correspondingly, the third cam structure <NUM> is also the same as the second cam structure <NUM>.

Specifically, the second cam portion <NUM> is also provided with a first concave portion <NUM>. The disposing direction of the first concave portion <NUM> on the second cam portion <NUM> is the same as the disposing direction of the first concave portion <NUM> on the first cam portion <NUM>, that is, the first concave portion <NUM> on the first cam portion <NUM> is disposed in a direction towards the second cam portion <NUM>, and the first concave portion <NUM> on the second cam portion <NUM> is disposed in a direction away from the first cam portion <NUM>.

The third cam structure <NUM> is also provided with a second concave portion <NUM>, and the second concave portion <NUM> faces the second cam portion <NUM>. The second concave portion <NUM> of the third cam structure <NUM> also abuts on the first concave portion <NUM> of the second cam portion <NUM>.

As shown in <FIG>, further, the first connection portion <NUM> connects the first cam portion <NUM> and the second cam portion <NUM>. In this way, the first cam portion <NUM> and the second cam portion <NUM> will rotate synchronously.

It also should be noted that, in other embodiments of this application, the first cam structure <NUM> may alternatively include only the first cam portion <NUM>, but does not include the second cam portion <NUM>. In this solution, the folding mechanism <NUM> includes two first cam structures <NUM>, one second cam structure <NUM>, and two springs <NUM>.

In an example of this application, the second cam structure <NUM> is made of stainless steel. It can be understood that the stainless steel is a non-wear-resistant material, that is, when friction acts on the stainless steel, an amount of wear of the stainless steel is greater than that of the wear-resistant material. To improve wear resistance of the second cam structure <NUM>, a wear-resistant layer is usually disposed on the outer surface of the second cam structure <NUM>. However, in a use process, the foldable smartphone needs to be folded or unfolded frequently. Therefore, friction frequently occurs between the second cam structure <NUM> and the first cam structure <NUM>. Because the thickness of the wear-resistant layer is usually small, after the wear-resistant layer is completely worn, a stainless steel body of the second cam structure <NUM> will be gradually worn by a greater amount, a damping force provided by the folding mechanism <NUM> is gradually reduced, and when the user folds or unfolds the foldable smartphone to an angle, the folding angle may be increased or decreased due to an accidental touch, which affects user experience.

Based on this, as shown in <FIG>, an embodiment of this application provides a cam assembly <NUM>, and the appearance of the cam assembly <NUM> may be the same as the appearance of the foregoing second cam structure <NUM>. In this embodiment, the cam assembly <NUM> includes a cam body <NUM> and a frame <NUM> embedded into the cam body <NUM>.

As shown in <FIG>, the cam body <NUM> includes two cams <NUM> and a connection body <NUM>, where the two cams <NUM> are oppositely disposed, and the connection body <NUM> is located between the two cams <NUM>.

As shown in <FIG>, the cam <NUM> is of a hollow structure with openings at two ends. The cam <NUM> is provided with a third end face <NUM> and a fourth end face <NUM> that are opposite to each other, the third end face <NUM> is a plane and is flush with the connection body <NUM>, and the fourth end face <NUM> is higher than the connection body <NUM>. Three third concave portions <NUM> are formed on the fourth end face <NUM>, and the third concave portion <NUM> is in a shape with a small bottom and a big top. One side surface of the third concave portion <NUM> is an abutting surface <NUM> configured to interact with the first cam structure <NUM>.

It should be noted that, in other embodiments of this application, there may be one, two, four, or more third concave portions <NUM> on each cam <NUM>, which is not limited in the embodiments of this application.

As shown in <FIG>, an annular hole position <NUM> is provided in the cam <NUM> and in the circumferential direction of the cam <NUM>, and three longitudinal through holes <NUM> penetrating from the third end face <NUM> to the fourth end face <NUM> are provided in the cam <NUM>. A center line of the annular hole position <NUM> intersects with a center line of each longitudinal through hole <NUM>, and the hole diameter of the annular hole position <NUM> is the same as the hole diameter of each longitudinal through hole <NUM>.

In other embodiments of this application, a positional relationship between the annular hole position <NUM> and the longitudinal through hole <NUM> may be as follows: A center line of the annular hole position <NUM> does not intersect with a center line of the longitudinal through hole <NUM>, but the annular hole position <NUM> overlaps the longitudinal through hole <NUM>; or the annular hole position <NUM> does not overlap the longitudinal through hole <NUM>, and the two communicate with each other by using a hole position provided additionally.

As shown in <FIG>, the two cams <NUM> are of a symmetrical structure about the center of the connection body <NUM>. Specifically, the cams <NUM> have the same distance from the center of the connection body <NUM>, the quantities of the third concave portions <NUM> on the cams <NUM> may be the same, and the disposing positions of the third concave portions are symmetrical about the center of the connection body <NUM>. In this way, after the cam assembly <NUM> is applied to the folding mechanism <NUM>, in the process of folding or unfolding the foldable smartphone, forces, exerted by the first cam structure <NUM>, on two cam bodies of the cam assembly <NUM> through the third side surface <NUM> are also symmetrical about the center of the connection body <NUM>, so that the cam assembly <NUM> can be prevented from bearing an offset load force as much as possible, thereby avoiding the situation that the cam assembly <NUM> is prone to damage due to the offset load force. The entire cam body <NUM> can also be of a symmetrical structure about the center of the connection body <NUM>.

The material of the cam <NUM> is a wear-resistant material. It can be understood that the wear-resistant material usually has relative high wear resistance, so that when the cam <NUM> is made of the wear-resistance material, the entire cam <NUM> has relatively high wear resistance, that is, when the same magnitude of friction acts on the cam, the amount of wear of the cam <NUM> is smaller than that of other cams made of non-wear-resistant materials. In this way, after frequent and long-term friction, even if the surface is worn, the cam still has relatively high wear resistance, and does not lose a wear-resistant effect due to wear of the surface. Therefore, when the cam assembly <NUM> according to this embodiment of this application is applied to a foldable smartphone, because the cam always keeps relatively high wear resistance, and does not have the relatively large amount of wear, the service life of the cam assembly <NUM> can be prolonged. In addition, the folding mechanism <NUM> can further provide relatively stable damping. After the foldable smartphone is folded or unfolded to an angle, the folding angle is not increased or decreased due to accidental touch of the user, so that user experience can be improved.

The wear-resistant material may be a ceramic particle reinforced aluminum matrix composite, which is isotropic. The ceramic particle reinforced aluminum matrix composite includes matrix alloy and reinforcement particles, the matrix alloy may be aluminum alloy with relatively high strength, such as <NUM> series (Al-Cu series) aluminum alloy, <NUM> series (Al-Mg-Si series) aluminum alloy, or <NUM> series (Al-Zn-Mg-Cu series) aluminum alloy. The reinforcement particles may be ceramic particles with relatively high rigidity, such as SiC, Al<NUM>O<NUM>, TiC, or TiB<NUM>. The volume fraction of the reinforcement particles is <NUM>%-<NUM>%, and the size of the reinforcement particles is <NUM>-<NUM>. The density of the ceramic particle reinforced aluminum matrix composite can be greater than <NUM>%. In this way, the wear-resistant material has relatively high wear resistance and moderate strength. In addition, the density of the wear-resistant material is small, which further reduces the weight.

As shown in <FIG>, in this embodiment of this application, the cross-section of the connection body <NUM> is a rectangle. In other embodiments of this application, the cross-section of the connection body <NUM> may be a square, circle, or the like. It should be noted that, in this embodiment, the connection body <NUM> is a long strip, and the length direction of the connection body is an extension direction from one cam <NUM> to another cam <NUM>, a cutting plane perpendicular to the length direction of the connection body <NUM> can be defined, and thus the cross-section of the connection body <NUM> refers to a surface captured along the cutting plane.

As shown in <FIG>, two end faces of the connection body <NUM> fit the outer surfaces of the cams <NUM>. For example, when the outer surface of the cam <NUM> is a cylindrical surface, the end face that is of the connection body <NUM> and that is connected to the cam <NUM> is also an arc surface having the same diameter as the cylindrical surface. In this way, it is convenient for processing the cam assembly <NUM> by using a casting processing method, or when a welding processing method is used, a stress generated at the joint of the connection body <NUM> and the cam <NUM> can be reduced, so that the strength of the cam assembly <NUM> can be improved, and cracks or even fractures generated when the cam assembly bears a force can be reduced.

As shown in <FIG>, the connection body <NUM> is provided with a fifth end face <NUM> connected to one cam <NUM>, and a sixth end face <NUM> connected to the other cam <NUM>. The connection body <NUM> is provided with a transverse through hole <NUM> penetrating from the fifth end face <NUM> to the sixth end face <NUM>, and both ends of the transverse through hole <NUM> communicate with the annular hole position <NUM>.

As shown in <FIG>, in this embodiment of this application, the transverse through hole <NUM> is a circular hole, and the hole diameter of the transverse through hole <NUM> is the same as the hole diameter of the annular hole position <NUM>. In other embodiments of this application, the hole diameter of the transverse through hole <NUM> is different from the hole diameter of the annular hole position <NUM>.

In this embodiment of this application, the material of the connection body <NUM> may also be the wear-resistant material. In this way, the cam <NUM> and the connection body <NUM> are of the same material, and thus the entire cam body <NUM> can be manufactured in an integral forming manner. In addition, the density of the wear-resistant material is small, which further reduces the weight.

In other embodiments of this application, the connection body <NUM> may alternatively be made of other materials with high strength, such as stainless steel or Q345B. The cam body <NUM> may be manufactured in a split forming manner. For example, the two cams <NUM> and the connection body <NUM> can be separately manufactured, and then welds are formed at the joints between the two cams <NUM> and the connection body <NUM>, that is, the cam body <NUM> is manufactured by using a welding method.

In this embodiment of this application, as shown in <FIG>, the frame <NUM> includes two fasteners <NUM> and a connector <NUM>, where the connector <NUM> is fastened between the two fasteners <NUM>. Because the cam body <NUM> is of a symmetrical structure about the center of the connection body <NUM>, correspondingly, the frame <NUM> is also of a symmetrical structure about the center of the connector <NUM>.

As shown in <FIG>, the fastener <NUM> includes three arc-shaped fastening bodies <NUM>, three first fastening columns <NUM>, and three second fastening columns <NUM>. The three arc-shaped fastening bodies <NUM> are arranged in a circle, and every two arc-shaped fastening bodies <NUM> are connected to each other. One first fastening column <NUM> and one second fastening column <NUM> are fastened at the joint of every two arc-shaped fastening bodies <NUM>, and the first fastening column <NUM> and the second fastening column <NUM> are respectively fastened on two side surfaces of the arc-shaped fastening body <NUM>.

As shown in <FIG>, the three arc-shaped fastening bodies <NUM> of the fastener <NUM> are all fastened in the annular hole position <NUM> of the cam <NUM>, and the arc-shaped fastening bodies <NUM> fit the annular hole position <NUM>. For example, the shape of the outer surface of the arc-shaped fastening body <NUM> is the same as the shape of the annular hole position <NUM>, and the size of the outer surface of the arc-shaped fastening body <NUM> is the same as or similar to the size of the inner surface of the annular hole position <NUM>. For example, when the annular hole position <NUM> is a circular hole, the cross-section of the arc-shaped fastening body <NUM> is also a circle.

It should be noted that three directions can be defined: the axial direction of the cam <NUM>, the circumferential direction of the cam <NUM> and the radial direction of the cam <NUM>. Therefore, the cross-section of the arc-shaped fastening body <NUM> is a plane captured along a cutting plane perpendicular to the circumferential direction of the cam <NUM>.

As shown in <FIG>, both the first fastening column <NUM> and the second fastening column <NUM> are fastened in the longitudinal through hole <NUM>, an end face of the first fastening column <NUM> is flush with the fourth end face <NUM> of the cam <NUM>, and an end face of the second fastening column <NUM> is flush with the third end face <NUM> of the cam <NUM>. In this way, the fastener <NUM> penetrates from the third end face <NUM> to the fourth end face <NUM> of the cam <NUM>, which can provide better support for the cam body <NUM>, to further improve the strength of the cam body <NUM>, and to reduce the occurrence of fractures of the cam body <NUM> when the cam body bears an extrusion force.

Still referring to <FIG>, each joint <NUM> includes two arc-shaped fastening bodies <NUM>: a first fastening column <NUM> and a second fastening column <NUM>. To ensure reliable connections between the arc-shaped fastening bodies <NUM>, the first fastening column <NUM>, and the second fastening column <NUM>, two symmetrical notches can be provided in each of the arc-shaped fastening bodies <NUM>, the first fastening column <NUM>, and the second fastening column <NUM>, so that a sharp corner and two slopes are formed at one end of each of the arc-shaped fastening bodies <NUM>, the first fastening column <NUM>, and the second fastening column <NUM>. Therefore, each component can be in close contact with the slopes of the adjacent components, and then welding is performed for fastening, which can reduce a welding stress, thereby improving the strength of connection parts, and then improving the strength of the entire frame <NUM>.

As shown in <FIG>, the connector <NUM> is fastened in the transverse through hole <NUM>, and the outer surface of the connector <NUM> fits the inner surface of the transverse through hole <NUM>. The connector <NUM> may be a connection column, and the cross-section of the connection column is a circle. It should be noted that the cross-section of the connection column is a plane captured along a cutting plane perpendicular to the axial direction of the cam.

The frame <NUM> may also be made of another material with high strength, such as stainless steel or Q345B. Because a wear-resistant material usually has low strength, the frame <NUM> made of a high-strength material can be embedded into the cam body <NUM> made of the wear-resistant material, which can improve the strength of the cam assembly <NUM>, that is, the wear resistance of the cam assembly <NUM> is improved while relatively high strength of the cam assembly <NUM> is ensured.

It should be noted that the connection body <NUM> in this embodiment and the connector <NUM> fastened in the connection body can constitute a second connection portion <NUM> shown in <FIG>. The cam <NUM>, the arc-shaped fastening bodies <NUM> fastened in the cam, and the first fastening columns <NUM> and the second fastening columns <NUM> fastened in the longitudinal through holes <NUM> can constitute a third cam portion <NUM> shown in <FIG>.

In another embodiment of this application, a difference from the embodiment shown in <FIG> lies in the different structure of the fastener <NUM> of the frame <NUM>. Specifically, in this embodiment, the three arc-shaped fastening bodies <NUM> in the embodiment shown in <FIG> are replaced by a fastening ring <NUM>. The fastener <NUM> includes a fastening ring <NUM>, three first fastening columns <NUM>, and three second fastening columns <NUM>, and the three first fastening columns <NUM> and the three second fastening columns <NUM> are respectively fastened on two sides of the fastening ring <NUM>. End faces of the fastening ring <NUM> are closed, and the fastening ring <NUM> may be of an integrally formed structure, for example, the fastening ring <NUM> can be formed with round steel. In another embodiment of this application, a difference from the embodiment shown in <FIG> lies in the different structure of the fastener <NUM> of the frame <NUM>. Specifically, as shown in <FIG>, in this embodiment, the three arc-shaped fastening bodies <NUM> in the embodiment shown in <FIG> is replaced by a fastening ring <NUM>, and the first fastening columns <NUM> and the second fastening columns <NUM> in the embodiment shown in <FIG> are replaced by third fastening columns <NUM>. In this embodiment, the fastener <NUM> includes a fastening ring <NUM> and three third fastening columns <NUM>, the three third fastening columns <NUM> are all fastened on the outer side of the fastening ring <NUM>, and two ends of the three third fastening columns <NUM> extend out of the fastening ring <NUM>. The third fastening column <NUM> is of an integrated structure, for example, the third fastening column <NUM> can be obtained by cutting round steel.

In another embodiment of this application, a difference from the embodiment shown in <FIG> lies in different fastening positions of the third fastening columns <NUM> on the fastening ring <NUM>. Specifically, as shown in <FIG>, in this embodiment, the three third fastening columns <NUM> are all fastened on the inner side of the fastening ring <NUM>.

In another embodiment of this application, a difference from the embodiment shown in <FIG> lies in the different structure of the fastener <NUM> of the frame <NUM>. Specifically, in this embodiment, the first fastening columns <NUM> and the second fastening columns <NUM> in the embodiment shown in <FIG> are replaced by third fastening columns <NUM>. In this embodiment, the fastener <NUM> includes three arc-shaped fastening bodies <NUM> and three third fastening columns <NUM> arranged in a circle, one third fastening column <NUM> are connected between every two arc-shaped fastening bodies <NUM>, and both two ends of the three third fastening columns <NUM> extend out of the arc-shaped fastening body <NUM>.

In another embodiment of this application, a difference from the embodiment shown in <FIG> lies in the cross-section shapes of the fastener <NUM> and the connector <NUM> in the frame <NUM>. The cross-sections of both the fastener <NUM> and the connector <NUM> in the embodiment shown in <FIG> are circles, and in this embodiment, the cross-sections of both the fastener <NUM> and the connector <NUM> in this embodiment are rectangles.

Specifically, as shown in <FIG>, the fastener <NUM> includes a fastening ring <NUM> and three third fastening columns <NUM>, and the three third fastening columns <NUM> are all fastened on the outer side of the fastening ring <NUM>.

As shown in <FIG>, the cross-section of the fastening ring <NUM> is a rectangle, and the fastening ring <NUM> is of an integrally formed structure. Therefore, the fastening ring <NUM> can be obtained by bending a steel plate. When the cross-section of the fastening ring <NUM> is a rectangle, long sides of the rectangular cross-section are disposed in the axial direction of the cam. It should be noted that the cross-section of the fastening ring <NUM> is a plane captured along a cutting plane perpendicular to the circumferential direction of the cam.

As shown in <FIG>, when the cross-section of the third fastening column <NUM> is a rectangle, long sides of the rectangular cross-section of the third fastening column <NUM> are disposed in the radial direction of the cam, and therefore the strength of the cam assembly <NUM> can be further improved.

As shown in <FIG>, when the cross-section of the connector <NUM> is a rectangle, long sides of the rectangular cross-section of the connector <NUM> are disposed in the axial direction of the cam.

In other embodiments of this application, the cross-section of the fastening ring <NUM> or the third fastening column <NUM> may also be a triangle, pentagon, or another polygon.

In another embodiment of this application, a difference from the embodiment shown in <FIG> lies in different fastening positions of the third fastening columns <NUM> on the fastening ring <NUM>. Specifically, as shown in <FIG>, the three third fastening columns <NUM> are all fastened on the inner side of the fastening ring <NUM>.

In other embodiments of this application, in the three fastening columns <NUM>, some of the fastening columns <NUM> can be fastened on the inner side of the fastening ring <NUM>, and the remaining third fastening columns <NUM> are fastened on the outer side of the fastening ring <NUM>, which is not limited in the embodiments of this application.

A method for processing a cam assembly <NUM> of the embodiments of this application is described below:
When the material of an entire cam body <NUM> is a wear-resistant material, the entire cam assembly <NUM> can be manufactured by using an insert casting method, specifically including:.

It should be noted that, in this embodiment of this application, in the process of preparing the cam body <NUM> of the cam assembly <NUM>, any of different types of ceramic particles may be used, and forming modes used for the semifinished part of the cam assembly may be varied when the different types of ceramic particles and the ceramic particles with different volume fractions are used. For example, when the volume fraction of the particles is relatively low (<NUM>%-<NUM>%), the semifinished part of the cam assembly can be prepared by using a particle adding and stirring method (the ceramic particles are SiC, Al<NUM>O<NUM>, and the like. ) or an in-situ synthesis method (the ceramic particles are TiC, TiB<NUM>, Al<NUM>O<NUM>, and the like. ); or when the volume fraction of the particles is moderate (<NUM>%-<NUM>%), the semifinished part of the cam assembly can be prepared by using a powder metallurgic method; or when the volume fraction of the particles is relatively high (<NUM>%-<NUM>%), the semifinished part of the cam assembly can be prepared by using an infiltration method. Step <NUM>: Perform die forging and heat treatment on the semifinished part of the cam assembly.

Perform die forging on the semifinished part of the cam assembly to improve the density of the semifinished part to more than <NUM>%, and then perform heat treatment on the semifinished part to obtain a cam assembly after heat treatment.

Step <NUM>: Manufacture a finished product of the cam assembly.

Perform surface finishing on the cam assembly after heat treatment, to obtain a formed part with the size and surface quality meeting requirements.

Claim 1:
A cam assembly (<NUM>), applied to a folding mechanism (<NUM>), wherein the folding mechanism (<NUM>) comprises a cam structure (<NUM>), and the cam structure (<NUM>) comprises a cam body (<NUM>) and a frame (<NUM>), wherein
the cam body (<NUM>) comprises a first cam (<NUM>) and a second cam that are oppositely disposed, and a connection body (<NUM>) located between the first cam (<NUM>) and the second cam, and a concave portion (<NUM>) cooperating with the cam structure (<NUM>) is disposed at one end of the cam body (<NUM>); and
the frame (<NUM>) comprises a first fastener (<NUM>) and a second fastener that are oppositely disposed, and a connector (<NUM>) located between the first fastener (<NUM>) and the second fastener, wherein the cam assembly (<NUM>) is characterized in that materials of both the first cam and the second cam comprise a wear-resistant material, the first fastener (<NUM>) is embedded into the first cam (<NUM>), the second fastener is embedded into the second cam, extension directions of the first fastener (<NUM>) in the first cam (<NUM>) comprise at least the axial direction and the circumferential direction, extension directions of the second fastener in the second cam comprise at least the axial direction and the circumferential direction, and the connector (<NUM>) is embedded into the connection body (<NUM>).