Injector

An injection device including a heating cylinder and a screw, the injection device comprising:

• a front plate to which the heating cylinder is fixed;
• a rear plate provided with a forward and backward movement mechanism that moves the screw forward and backward in an axial direction thereof;
• a pair of side support plates connecting the front plate and the rear plate at left and right end portions thereof, and
• an intermediate member slidably mounted on the side support plates, a rear end portion of the screw being axially supported by the intermediate member,
• wherein a guide member that guides the intermediate member to be slidably movable is provided on an upper surface of each of the side support plates, and a bending buffer portion is provided in a first region of each of the side support plates which is located more outward than a part of each of the side support plates on which the guide member is provided, the bending buffer portion being configured to be bent and deformed easier than a second region of each of the side support plates in which the guide member is provided,
• wherein each of the side support plates includes the first region provided on a front portion of each of the side support plates, which is located at a more distal portion than the part of the side support plates on which the guide member is provided in a longitudinal direction, and an other first region provided on a rear portion of each of the side support plates, opposite of the front portion of each of the side support plates in the longitudinal direction and also located at a more distal portion than the part of the side support plates on which the guide member is provided,
• wherein the bending buffer portion is provided in both the first region and the other first region,
• wherein a forward and backward movement driver is configured to drive the forward and backward movement mechanism,
• wherein the forward and backward movement driver is fixed to an upper portion of the rear plate entirely above one of the side support plates, and adjacent to a rotation device configured to rotate the screw, and the forward and backward movement driver is configured to engage with the forward and backward moving mechanism via a timing belt wound around pullies positioned at a rear end of the injection device,
• wherein the bending buffer portion includes a recess formed in only an outer surface of each of the side support plates, so that the thickness of the bending buffer portion is thinner than the thickness of the second region, and
• wherein the recess is provided at a constant thickness continuously over an entirety of a width direction of each of the side support plates.