Background
In the field of machining, positioning and position adjustment of a workpiece to be machined are generally performed by means of a robot equipped with a gripper. Two-jaw grippers currently include telescoping cylinder driven grippers and lead screw driven grippers.
The telescopic cylinder driving type clamp comprises two clamps and two telescopic cylinders for driving the two clamps to pivot respectively, and the motion of each clamp is controlled by the extension and contraction of each telescopic cylinder, so that the two clamps can be folded or unfolded. Because the synchronous motion performance between two telescoping cylinders is poor, the asynchronous motion of two clamps is easily caused, and the clamping precision is poor.
The lead screw driven type clamp can overcome the aforementioned problems of the aforementioned telescopic cylinder driven type clamp. In the clamp disclosed in chinese patent document CN205600356U, a left-hand thread and a right-hand thread are provided at both ends of a threaded portion of a lead screw, respectively, a space is provided between the left-hand thread and the right-hand thread, a left jaw is connected to the left-hand thread by a left-hand nut, and a right jaw is connected to the right-hand thread by a right-hand nut. When the gripper is used for grabbing an object, the screw rod is driven by the motor to move, and then the screw rod drives the left clamping jaw and the right clamping jaw to approach or separate from each other. Although the synchronous movement performance of the left clamping jaw and the right clamping jaw of the gripper is good, the axial space occupied by the screw rod is overlarge, the structure of the gripper and the clamping jaws thereof is not compact, and the gripper is overlarge in size and heavier in weight. When large-size objects need to be grabbed, the gripper not only causes great load burden to the manipulator, but also causes the manipulator not to easily enter a narrow space to grab.
Disclosure of Invention
The application aims at providing a compact structure's holder, and this application still provides a manipulator.
The present application provides a gripper comprising: a screw including a screw portion and a driving portion; the spiral part is provided with at least one first spiral track and at least one second spiral track, and the rotation directions of the first spiral track and the second spiral track are opposite; wherein a first end of the first spiral track corresponds to a first end of the spiral portion, and a second end of the first spiral track extends toward a second end of the spiral portion; a second end of the second helical track corresponds to a second end of the helical portion, the first end of the second helical track extending towards the first end of the helical portion; the first spiral track and the second spiral track which are crossed are arranged on at least part of the length of the spiral part; a first jaw and a second jaw; wherein the first jaw has at least one first pin that extends into the first helical track; the second jaw has at least one second pin that extends into the second helical track; wherein the first jaw and the second jaw are configured to: when the driving portion drives the spiral portion to rotate, the first spiral track drives the first pin to enable the first clamping jaw to conduct linear motion along the direction parallel to the screw rod, and the second spiral track drives the second pin to enable the second clamping jaw to conduct linear motion along the direction opposite to the linear motion direction of the first clamping jaw.
Further, the holder further comprises: the first guide mechanism is connected with the first clamping jaw in a sliding mode so as to guide the linear motion of the first clamping jaw; and the second guide mechanism is connected with the second clamping jaw in a sliding mode so as to guide the linear motion of the second clamping jaw.
Further, the first clamping jaw further comprises a first clamping part and a first connecting part; the first end of the first connecting part is connected with the first clamping part, and the second end of the first connecting part is connected with the first guide mechanism in a sliding manner; the first pin is arranged at the second end of the first connecting part; the second clamping jaw further comprises a second clamping part and a second connecting part; the first end of the second connecting part is connected with the second clamping part, and the second end of the second connecting part is connected with the second guide mechanism in a sliding manner; the second pin is disposed at a second end of the second connecting portion.
Further, the first guide mechanism comprises a first linear guide rail and a first sliding block, and the first connecting part is in sliding connection with the first linear guide rail through the first sliding block; the second guide mechanism comprises a second linear guide rail and a second sliding block, and the second connecting part is connected with the second linear guide rail in a sliding manner through the second sliding block; the first linear guide rail, the screw and the second linear guide rail are parallel to each other; or the first guide mechanism comprises a first guide rod, and the first connecting part is provided with a first hole in sliding connection with the first guide rod; the second guide mechanism comprises a second guide rod, and the second connecting part is provided with a second hole in sliding connection with the second guide rod; the first guide rod, the screw and the second guide rod are parallel to each other.
Further, the length of the first connecting portion and the second connecting portion in a direction parallel to the screw rod is adjustable.
Further, the at least one first spiral track includes two first spiral tracks that are arranged in parallel in an axial direction of the screw and spaced apart from each other; the at least one first pin comprises at least two first pins, and each first pin respectively extends into the corresponding first spiral track; and/or the at least one second helical track comprises two second helical tracks arranged in parallel and spaced apart from each other in the axial direction of the screw; the at least one second pin comprises at least two second pins, and each second pin extends into the corresponding second spiral track.
Further, the first pin is configured not to be at the intersection of the first helical track and the second helical track at the same time; the second pin is configured not to be at the intersection of the first helical track and the second helical track at the same time.
Further, the first spiral track and the second spiral track each extend over the entire length of the spiral portion.
Further, the first clamping jaw and the first guide mechanism are positioned on one side of the screw rod, and the second clamping jaw and the second guide mechanism are positioned on the other side of the screw rod; the clamp holder further comprises a power mechanism, and the power mechanism is connected with the driving part and used for driving the driving part to rotate.
The application also provides a manipulator, the manipulator is provided with foretell holder.
The utility model provides a clamp, first spiral track and second spiral track are crossed on at least partial length of screw portion, like this, allow the effective displacement stroke of first clamping jaw to be equal to the axial length of first spiral track basically, the effective displacement stroke of second clamping jaw is equal to the axial length of second spiral track basically, thereby make the effective displacement stroke sum of first clamping jaw and second clamping jaw be greater than the axial length of screw portion, can guarantee on the basis of the biggest centre gripping distance between first clamping jaw and the second clamping jaw, reduce the axial length of screw rod and its occupied space by a wide margin, help the miniaturization of clamp, compact design, and help reducing the weight of clamp.
Detailed Description
Fig. 1 to 6 show a structure of a holder provided in an embodiment of the present application. As shown in fig. 1 to 4, the gripper includes a screw 2, a first jaw 31, a second jaw 32, a first guide mechanism 1a, and a second guide mechanism 1 b.
The screw 2 includes a screw part 20 and a driving part 25, and the driving part 25 may be located at either or both ends of the screw part 20. Wherein, the spiral part 20 is provided with two first spiral tracks 201 and two second spiral tracks 202, and the rotation directions of the first bolt tracks 201 and the second spiral tracks 202 are opposite. Referring to fig. 2, two first spiral tracks 201 are arranged in parallel and spaced from each other in the axial direction of the screw 2, and two second spiral tracks 202 are also arranged in parallel and spaced from each other in the axial direction of the screw 2. A first end of each first spiral track 201 corresponds to a first end of the spiral part 20, and a second end of each first spiral track 201 extends towards a second end of the spiral part 20. A second end of each second helical track 202 corresponds to a second end of the helix 20, and a first end of each second helical track 202 extends toward the first end of the helix 20. For example, a first end of each first spiral track 201 is at a first end of the spiral 20, and a second end of each second spiral track 202 is at a second end of the spiral 20.
In some embodiments, a first helical track 201 and a second helical track 202 (which may also be referred to as helical intersections) are provided that intersect over at least a portion of the length of the helix 20. As can be seen in the figure, in the present embodiment, the second end of each first spiral track 201 extends to the second end of the spiral part 20, and the first end of each second spiral track 202 extends to the first end of the spiral part 20, so that the axial length of the spiral part 20 is equal to the axial length of the spiral cross section. That is, each of the first spiral tracks 201 and each of the second spiral tracks 202 extend over the entire length of the spiral portion 20. Of course, in other embodiments, the second end of each first helical track 201 may not extend to the second end of the helix 20, and/or the first end of each second helical track 202 may not extend to the first end of the helix 20, such that the first and second helical tracks 201, 202 may be partially intersecting.
The first jaw 31 and the second jaw 32 are each configured and adapted to move linearly in a direction parallel to the screw 2. There are various embodiments of the first jaw 31 and the second jaw 32 to make a linear motion parallel to the screw 2, in this embodiment, the first jaw 31 is slidably connected to the first guide mechanism 1a, and the first jaw 31 makes a linear motion under the guidance of the first guide mechanism 1 a. The second clamping jaw 32 is connected with the second guiding mechanism 1b in a sliding way, and the second clamping jaw moves linearly under the guidance of the second guiding mechanism 1 b. The first guide mechanism 1a and the second guide mechanism 1b will be described in detail hereinafter.
In this embodiment, the first jaw 31 may have a plurality of first pins 313, a part of the first pins 313 extending into one of the first spiral tracks 201, and another part of the first pins 313 extending into the other first spiral track 201. Each first pin 313 is slidably fitted with the corresponding first spiral track 201. That is, any one of the first spiral tracks 201 is slidably fitted with at least one first pin 313. Fig. 4 shows an embodiment of the first jaw 31, and the first pins 313 may be respectively installed in a plurality of pin holes 3121 on the first jaw 31. Thus, when the screw 2 rotates, the first spiral track 201 can push the first pin 313 to perform a linear motion parallel to the screw 2, and further drive the first clamping jaw 31 to perform a linear motion parallel to the screw 2. By providing a plurality of first pins 313, the balance of the forces applied to the first jaw 31 and the smoothness of movement are facilitated.
In this embodiment, the second jaw 32 may have a structure similar to that of the first jaw 31. Similarly, the second jaw 32 may have a plurality of second pins 323, a portion of the second pins 323 extending into one of the second helical tracks 202, and another portion of the second pins 323 extending into another of the second helical tracks 202. Each second pin 323 is slidably engaged with the corresponding second spiral track 202. That is, any one of the second spiral tracks 202 is slidably engaged with at least one second pin 323. Thus, when the screw 2 rotates, the second spiral track 201 can push the second pin 323 to make a linear motion parallel to the screw 2, and further drive the second clamping jaw 32 to make a linear motion parallel to the screw 2. It will be appreciated that the direction of movement of the first jaw 31 is opposite to the direction of movement of the second jaw 32. By providing a plurality of second pins 323, the balance of the force applied to the second jaw 32 and the smoothness of the movement are facilitated.
When the driving portion 25 of the screw 2 is driven to rotate, the driving portion 25 drives the screw portion 20 to rotate together in a first direction or in a second direction opposite to the first direction, that is, the first pin 313 and the second pin 323 can be respectively matched with the corresponding first spiral track 201 and the corresponding second spiral track 202, so that the relative movement between the first clamping jaw 31 and the second clamping jaw 32 can be realized.
In some embodiments, when the at least one first pin 313 is located at the first end of the corresponding first spiral track 201 (as long as one first pin 313 is close to the first end of the first spiral track 201) and the at least one second pin 323 is located at the second end of the corresponding second spiral track 202 (as long as one second pin 323 is close to the second end of the second spiral track 202), the first jaw 31 and the second jaw 32 are in a state of being away from each other with the clamping distance therebetween being the maximum clamping distance (i.e., the first jaw 31 and the second jaw 32 are opened to the maximum). As shown in fig. 1.
According to the embodiment provided by the present application, when the screw 2 is rotated, the first pins 313 can be moved from the first end to the second end of the first spiral track 201 (as long as one first pin 313 is close to the second end of the corresponding first spiral track 201), while the second pins 323 can be moved from the second end to the first end of the second spiral track 202 (as long as one second pin 323 is close to the first end of the corresponding second spiral track 202). At this time, the first jaw 31 and the second jaw 32 are in a state of being close to each other with the clamping distance therebetween being a minimum clamping distance (the first jaw 31 and the second jaw 32 are closed to a minimum extent). In this embodiment, as shown in fig. 3, the minimum clamping distance is zero. In other embodiments, the minimum clamping distance may be greater than zero.
The clamp provided by the embodiment, the first spiral track 201 and the second spiral track 202 are crossed on at least part of the length of the spiral part 20, and by reasonably designing the configuration of the first clamping jaw 31 and the second clamping jaw 32, the problem that the effective stroke of the first spiral track 201 and the second spiral track 202 is shortened due to interference of the first clamping jaw 31 and the second clamping jaw 32 when the first pin 313 and the second pin 323 pass through the spiral crossed section can be avoided. In the present embodiment, the effective movement stroke of the first clamping jaw 31 is substantially equal to the axial length of each first spiral track 201, and the effective movement stroke of the second clamping jaw 32 is substantially equal to the axial length of each second spiral track 202, so that the sum of the effective movement strokes of the first clamping jaw 31 and the second clamping jaw 32 is greater than the axial length of the spiral part 20, and on the basis of ensuring the maximum clamping distance between the first clamping jaw 31 and the second clamping jaw 32, the axial length of the screw rod 2 and the occupied space thereof are greatly reduced, which contributes to the miniaturization and compact design of the gripper, and the weight reduction of the gripper.
It will be appreciated that, in the case of equal maximum clamping distances, the axial length of the screw 2 can be minimized when the helix 20 and the helical cross section coincide, in which case the sum of the effective travel of the first jaw 31 and the second jaw 32 is equal to about twice the axial length of the helix 20. In addition, the speed of change of the gripping distance between the first jaw 31 and the second jaw 32 is also increased accordingly.
It should be noted that, although two first spiral tracks 201 and two second spiral tracks 202 are provided in the present embodiment, in other embodiments, the number of the first spiral tracks 201 and the second spiral tracks 202 is not limited to two, and may be one or more than two, for example. At this time, the number of the first pins 313 and the second pins 323 may be changed accordingly. In addition, the number of the first pins 313 protruding into the same first spiral track 201 may be one, two or more. The number of the second pins 323 protruding into the same second spiral track 202 may be one, two or more. Referring to fig. 5, in the present embodiment, the number of the first pins 313 may be three, and the number of the second pins 323 may also be three.
In some embodiments, the positions of the plurality of first pins 313 on the first jaw 31 and the positions of the plurality of second pins 323 on the second jaw 32 are appropriately set to ensure that at least two first pins 313 are not at the intersection of the first spiral track 201 and the second spiral track 202 at the same time when moving along the first spiral track 201 and that at least two second pins 323 are not at the intersection of the first spiral track 201 and the second spiral track 202 at the same time when moving along the second spiral track 202. In this way, during the rotation of the screw 20, it is ensured that the at least one first pin 31 and the at least one second pin 32 are normally driven by the first screw track 201 and the second screw track 202, respectively, without being affected by the intersection, ensuring the reliability of the movement of the first jaw 31 and the second jaw 32.
In an embodiment not shown, any two adjacent intersections of the first and second spiral tracks 201 and 202 are not on the same line on the surface of the spiral 20 and parallel to the axis of the spiral 20. The arrangement of the first pins 313 coincides with the arrangement of the pin holes 3121 where the first pins 313 are installed, and the second pins 323 are also arranged in a similar manner. So configured, the plurality of first pins 313 may reach the intersection of the first spiral track 201 and the second spiral track 202 at different times, and similarly, the plurality of second pins 323 may also reach the intersection of the first spiral track 201 and the second spiral track 202 at different times.
Referring to fig. 1 and 3, a preferred embodiment of first jaw 31 and second jaw 32 are shown in this embodiment. The first clamping jaw 31 includes a first clamping portion 311 and a first connecting portion 312. The first connecting portion 312 has a first end connected to the first clamping portion 311, and a second end extending laterally from the first clamping portion 311 and adapted to be slidably connected to the first guide mechanism 1 a. The first pin 313 is disposed at a second end of the first connection portion 312. The second jaw 32 includes a second clamping portion 321 and a second connecting portion 322. The second connecting portion 322 has a first end connected to the second clamping portion 321, and a second end extending laterally from the second clamping portion 321 and adapted to be slidably connected to the second guide mechanism 1 b. The second pin 323 is disposed at a second end of the second connection portion 322. The distance between the first grip portion 311 and the second grip portion 321 in the direction parallel to the screw 2 is referred to as a grip distance, and the gripper grips or releases a gripped article by the first grip portion 311 and the second grip portion 321. It can be understood that, in order to avoid interference of the movements of the first clamping portion 311 and the second clamping portion 321, the direction in which the first connecting portion 312 extends from the first clamping portion 311 coincides with the axial direction of the screw 2 from the first end to the second end, and the direction in which the second connecting portion 322 extends from the second clamping portion 321 coincides with the axial direction of the screw 2 from the second end to the first end. Preferably, when the gripper is opened to the maximum gripping distance, the first gripping portion 311 is located beyond the first end of the screw 20 and the second gripping portion 321 is located beyond the second end of the screw 20. When the grippers are closed to the minimum gripping distance, the first gripping portion 311 and the second gripping portion 321 move to the middle portion of the screw 20, respectively.
In some embodiments, the lengths of the first and second connection portions 312 and 322 in a direction parallel to the screw 2 are adjustable. For example, the first connection portion 312 and the second connection portion 322 are respectively telescopic arms to meet different clamping requirements. In addition, in the present embodiment, the first connection portion 312 and the second connection portion 322 extend parallel to the screw 2, but of course, in other embodiments, the first connection portion 312 and the second connection portion 322 may extend, for example, obliquely with respect to the screw 2.
The first connecting portion 312 may be slidably connected to the first guide mechanism 1a by any suitable means to guide the first clamping jaw 31 to move linearly in a direction parallel to the screw 2. Similarly, the second connecting portion 322 may be slidably connected to the second guiding mechanism 1b by any suitable means to guide the second clamping jaw 32 to move linearly in a direction parallel to the screw 2. As mentioned above, the directions of movement of the first jaw 31 and the second jaw 32 are always opposite.
Also shown in this embodiment are preferred embodiments of the first guide means 1a and the second guide means 1 b. The first guide mechanism 1a includes a first linear guide 11 and a first slider 111, the first linear guide 11 is parallel to the screw rod 2, and the second end of the first connection portion 312 is slidably connected to the first linear guide 11 through the first slider 111. For example, referring to fig. 5, the second end of the first connection portion 312 is provided with a plurality of mounting holes 3120, and a plurality of fasteners passing through the mounting holes 3120 are connected to the first slider 111, thereby fixing the second end of the first connection portion 312 to the first slider 111. The second guide mechanism 1b includes a second linear guide rail 12 and a second slider 121, the second linear guide rail 12 is parallel to the screw rod 2, and the second end of the second connecting portion 322 is slidably connected to the second linear guide rail 12 through the second slider 121. In order to further optimize the structure of the gripper and make the gripper more compact, the screw 2 may be located in the middle of the first guide mechanism 1a and the second guide mechanism 1b, such that the first jaw 31 and the first guide mechanism 1a are located on one side of the screw 2 and the second jaw 32 and the second guide mechanism 1b are located on the other side of the screw 2. More preferably, the screw 2 may be located between the first linear guide 11 and the second linear guide 12.
In an embodiment not shown, the first guiding mechanism 1a may comprise a first guide rod parallel to the screw 2, the first connection portion 312 being provided with a first hole in sliding connection with the first guide rod. The second guiding mechanism 1b may include a second guide rod parallel to the screw 2, and the second connecting portion 322 is provided with a second hole slidably connected with the second guide rod. Preferably, the screw 2 may be located between the first guide bar and the second guide bar.
The embodiments of the first guide mechanism 1a and the second guide mechanism 1b are not limited to the above examples, as long as they can restrict the rotation of each of the first jaw 31 and the second jaw 32 with respect to the screw 2.
Referring to fig. 6, the clamp provided in this embodiment may further include a power mechanism 4, and the power mechanism 4 is connected to the driving portion 25 of the screw 2. The power mechanism 4 can drive the screw 2 to rotate in a first direction or rotate in a second direction opposite to the first direction, so that the first pin 313 and the second pin 323 linearly move in opposite directions to move the first clamping portion 311 and the second clamping portion 312 toward or away from each other.
The power mechanism 4 may include a motor 41 and a decelerator 42, and the decelerator 42 is connected between the motor 41 and the driving part 25 of the screw 2. Alternatively, as shown in the present embodiment, the power mechanism 4 may include a motor 41, a reducer 42, and a transmission mechanism 43, and the power mechanism 4 may be mounted on the base 5, for example. Wherein the motor 41 is connected to the decelerator 42, the motor 41 and the decelerator 42 are preferably located together below the screw 2, and the transmission mechanism 43 is used to transmit the power output from the decelerator 42 to the driving part 25 of the screw 2. The transmission 43 may be a chain transmission, a belt transmission, a gear transmission, or the like. The screw 2, the motor 41 and the speed reducer 42 are located on the same side of the transmission mechanism 43. Therefore, the structure of the gripper is more compact, the axial space occupied by the gripper is smaller, and the gripper is more favorable for entering a narrower space to grab articles.
The embodiment of the application also provides a manipulator, and the manipulator is provided with the clamp holder. Because of the holder of this application can reach above-mentioned technological effect, the manipulator that possesses this holder also can reach corresponding technological effect, can stretch into and snatch article in the narrow and small space.
The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the claims.
It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.